In article <[email protected]>, "Lew Hodgett" wrote:
> Doug Miller wrote:
>> +++++
>>
>> "When a c'bkr is in a panel, it is derated by 20% to handle the panel heat
>> generated by adjacent c'bkrs.." -- nonsense. Circuit breakers are *required*
>> by Code to be placed in a panel or other similar fixture [Article 240.30] and
>> no derating is applied for doing so.
>
>Name plate ratings of molded case thermal-magnetic c'bkrs are for bkrs in
>free air.
>
>As soon as the bkr is placed in an enclosure, detating applies.
Got a Code cite for that?
I didn't think so.
>> "#14 can only handle 15*80%=12A on a continuous basis." Correct, but
>> incomplete and potentially misleading, as it omits the Code definition of a
>> continuous load: "where the maximum current is expected to continue for 3
>> hours or more." [Article 100] This is *not* a usual, typical, normal
>> condition.
>
>Three (3) hours doesn't meet the definition of "continuous" in my world.
The definition of "continuous" in your world, wherever that may be, is
irrelevant. The only meaningful definition, for purposes of determining Code
compliance, is that provided by Article 100 of the NEC: "a load where the
maximum current is expected to continue for 3 hours or more."
And *that* is where the 20% derating applies: to continuous loads as defined
by the NEC. Not as defined by Lew.
Now go take your meds and read your code book again. This time try to
understand what you read.
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
In article <[email protected]>, "Rod & Betty Jo" <[email protected]> wrote:
>Doug Miller wrote:
>> In article <[email protected]>, "no
>> spam" <[email protected]> wrote:
>>
>>> Personally, when it comes to wiring bigger IS better.
>>
>> Nonsense. Except on very long runs, bigger wire provides no
>> advantages at all,
>> and does provide significant disadvantages:
>> a) higher cost
>> b) greater difficulty in installation
>> c) difficulty in finding compatible receptacles (for example, try
>> finding a 15A rated receptacle that will accept AWG8 wire)
>> d) the larger the wire, the fewer of them the Code allows you to put
>> in a box.
>
>
>Just curious.....aren't most electrical fires related to junctions,
>switches, receptacles and things plugged into them? In other words aren't
>strait wire runs the least problematic of any potential electrical fault as
>well? Rod
Exactly right in all respects, Rod.
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
10 or 12 is the wire size, 2 or 3 the number of conductors. All Romex type
cable has a ground which is not referenced as an "official: conductor. 10/3
cable has 3 10awg power carrying conductors and a ground. The 3 conductors
are white (neutral) Black and Red (hots) and is used in balanced 240/120
volt circuits (120 from each hot to neutral, 240 across the hots) 10/2 has
a white and black and is used in 120volt circuits only.
You have 2 issues in wiring a shop, the size of the conductors and the type
of circuits.
Size your conductors based on length of run and branch current rating. 12
awg is standard for 20amp, but I would use 10 for longer runs.
When I designed my shop I ran both general purpose 120volt, 20 namp
circuits and 240volt 20 amp circuits around the shop. the 120s are for the
light stuff, the 240s for larger tools like my lathe, DC etc.
I also ran several dedicated 240volt 50amp or larger circuits for stuff
like welders, compressors etc (Yes, I'm a turncoat, I also work metal!!)
Fri, 10 Aug 2007 14:19:22 -0700, [email protected] wrote:
>In recent posts I have heard mention of 12/2 and 10/2 wire, as well as
>12/3 and 10/3 wire. What is the difference and what would you wire a
>new shop with?
>
>I assume the 12/2 and 10/2 mean with ground.? What is the extra wire
>in the 12/3 and 10/3 for? Is that for wiring 220V?
>
>Jim
On Aug 11, 12:51 am, LRod <[email protected]> wrote:
> On Fri, 10 Aug 2007 14:19:22 -0700, [email protected] wrote:
>
> [electrical question snipped]
>
> You have just been introduced to the hazard of soliciting specialized
> advice on the internet.
I'll take that one step further. If a guy has to ask the difference
between 10/2, 10/3. 12/2 etc... WTF is he doing wiring his shop?
For chrissakes, call somebody who knows and who has the certification
and insurance!!
And GET A FARKING PERMIT!!
(Yes, yes, I know, I know... there are many here who have the
knowledge and confidence to do that kind of work themselves, but when
questions indicate a complete and total ignorance of the topic at
hand.........)
r
On Aug 10, 5:19 pm, [email protected] wrote:
> In recent posts I have heard mention of 12/2 and 10/2 wire, as well as
> 12/3 and 10/3 wire. What is the difference and what would you wire a
> new shop with?
In contemporary wiring, individual wires run in a sheathed cable. "Two-
wire with ground" and "three-wire with ground" cables are available.
Two-wire with ground cables have a black wire, a white wire and an
uninsulated ground. Three-wire with ground cables have a black wire, a
white wire, a red wire and an uninsulated ground. Older houses may
have "knob and tube" wiring-a two-wire system. With this system,
individual wires are insulated with white or black treated fabric.
http://www.lowes.com/lowes/lkn?action=howTo&p=Improve/ElecOver.html
Resulting from Google Search using "Home Electrical Wiring Basics."
On Aug 10, 5:35 pm, "Leon" <[email protected]> wrote:
> <[email protected]> wrote in message
>
> news:[email protected]...
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
"10/2 and 12/2 only have 2 wires."
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Gosh, bet that makes the Code Enforcement people very angry. This is
why you need to do your own, independent research. Lots of folks have
opinion they are willing to offer as answers on the "net." Of course,
all you had to do was drop by the hardware store, or Lowes, or HD, etc
where you could get a touchy feely answer and see for yourself.
> > In recent posts I have heard mention of 12/2 and 10/2 wire, as well as
> > 12/3 and 10/3 wire. What is the difference and what would you wire a
> > new shop with?
>
> > I assume the 12/2 and 10/2 mean with ground.? What is the extra wire
> > in the 12/3 and 10/3 for? Is that for wiring 220V?
>
> > Jim
>
> 10/3 and 12/3 are with ground. Also there are only 3 wires in those cables.
>
> 10/2 and 12/2 only have 2 wires.
Let me add to "Some other suggestions:"
>
**** Put your lights on a separate (3/4-way switch at each entry
point) circuit.
Instead of Keyless bulb fixtures, consider installing DUPELX outlets
in the ceiling with one side always on and the other switched. Then
use hanging fluorescent fixtures (48" two-bulb units $9 at Lowes/HD/
Wal-Mart) that you can easily replace and even move about should you
get a new tool for christmas. In a pince, you can always drop a short
cord from one of them (hot side) to feed an occasional use tool over
the table saw, say.
"Put in lots of outlet." Yes, and use two duplex utlets (double box)
at every four feet along your wall surface mounted 38" or so o the
floor. Te extra duplex outlet will add about seventy cents to teh cost
per and will be well worth it when you need another outlet.
Extend the switched circuit to the top right duplex outlet (isolate it
by breaking off the tab at the two "hot" screws) and paint it red.
This is the outlet to use to plug in those transformers for battery
chargers an such that continue to "draw" as long as they are plugged
in. When you switch off the lights, they are disonnected - saves $$$
and the ransformer(s). I also wired my air compressor into the
switched circuit so that it doesn't "recharge" at 3AM waking the wife
and sending me to the shop in my skivvys.
Plan. I used a thing called 3D Home to layout rooms before
constructon. Then measure and estimate wire needs so you can buy in
BULK as suggested to save $$.
I you can, wire in a sub-panel to feed the entire shop so all your
breakers are in the shop. If you use a Main Breaker sub-panel, you can
cut off all the power when you have to add that circuit you should
have :) or use it as a disconnect.
It's a pain when you pop a breaker
> and the lights go out.
>
> If you have large stationery tools, put in a dedicated circuit for each one.
>
> Put in lots of outlet. One for every three to four feet of wall at a
> minimum.
>
> Think about where you might put benches, etc. It helps to have plenty of
> outlets nearby, including some above the bench. I put all the outlets in my
> shop four feet above the floor.
On Aug 11, 9:29 am, "Leon" <[email protected]> wrote:
> "Mike Marlow" <[email protected]> wrote in message
>
> news:[email protected]...
>
>
http://www.electrical-online.com/planningacircuit.htm
Do-It-Yourself Repairs and Basic Wiring Projects:
Planning a Circuit
By Terry Peterman, the Internet Electrician
Summary: Planning a circuit in your home requires examining some
basic rules regarding the number of lights permitted on a circuit, and
recommendations for mounting boxes, receptacles and switches.
When planning to hook up a circuit, whether it is a new one directly
from the breaker panel or adding to an existing one, here are some
general rules to follow :
Maximum Lights Per Circuit
You are only allowed to put a maximum of 12 lights on one 15 amp
circuit, but try for between 8 and 10, if you are combining
receptacles and lights.
Remember that switches don't count as outlets. Run a separate circuit
for any large appliances, pumps, and motors etc.
Mounting Boxes
Start by marking the studs where you want your receptacles, switches,
and lights to be located. Then mount your outlet boxes.
Screws are required for octagon boxes but you can use either screws or
nails for switch and receptacle boxes. The important thing to remember
is to make the boxes secure because, once the drywall is on, it's hard
to re-attach them if they do work loose.
Don't forget that you must leave the boxes sticking out from the face
of the stud, slightly less than the thickness of the product that the
wall will be finished with.
Mounting Receptacles
Mount receptacles about 300 mm (12 inches) above the floor. The
general rule is that a receptacle is required for every 3.6 meters (12
feet) of usable wall space.
You are probably curious as to what useable wall space means
exactly...any measurement from the corner of a wall to a closet,
fireplace, or to where the door swings open is considered useable wall
space but, only if the wall is over 900 mm (3 feet) to begin with.
A receptacle is needed every 3.6 meters (12 feet) along a continuous
wall space so that at no time can a cord connected devise be any more
than 1.8 meters (6 feet) from an outlet. Also remember that there is
no maximum number of outlets, so make sure you have enough, and that
they are placed in convenient locations once the room is finished.
Mounting Switches
Mount switches on the inside of rooms opposite to the side that the
door opens. Make them as close as practical to the door opening, but
not so that the cover plate will interfere with the door casing.
The height is fairly flexible, but should be consistent and practical
(any where from 1.1 to 1.3 meters or 44 to 52 inches).
[email protected] wrote:
> In recent posts I have heard mention of 12/2 and 10/2 wire, as well as
> 12/3 and 10/3 wire. What is the difference and what would you wire a
> new shop with?
The first number is the wire guage, the second is the number of
conductors in the outer sheathing (not including ground).
As for what you would use, before wiring the shop you should have a good
picture of what types of equipment you'll have and where it will be.
You then simply wire accordingly. My shop has a mixture of #14, #12,
and #10 wiring, depending on purpose.
> I assume the 12/2 and 10/2 mean with ground.? What is the extra wire
> in the 12/3 and 10/3 for? Is that for wiring 220V?
The extra wire is used for a number of things. Among others, for
typical residential wiring it's used in 3-way light switches, mixed
240/120V loads (like a dryer), and in "split-wire" or "multi-wire" 120V
circuits.
For general-purpose circuits #14 can handle 15A, #12 can handle 20A, and
#10 can take 30A.
Chris
<[email protected]> wrote:
> In recent posts I have heard mention of 12/2 and 10/2 wire, as well as
> 12/3 and 10/3 wire. What is the difference and what would you wire a
> new shop with?
>
> I assume the 12/2 and 10/2 mean with ground.? What is the extra wire
> in the 12/3 and 10/3 for? Is that for wiring 220V?
Either 12/2 or 12/3 will contain a green ground conductor.
The ground is not included in the conductor count.
12/2 would be used for a 240V/1Ph/60Hz service.
OTOH, 12/3 would be used for a 120V-240V/1Ph/60Hz service.
Can't give a good answer about your shop other than to say that if you run 3
conductor circuits, you spend a few bucks, but down the road your fanny is
covered.
BTW, Lew's rule for shop wiring:
#12 AWG for all 1Pole(120V) circuits and #10AWG for all 2Pole(240V)
circuits.
Have fun.
Lew
"Chris Friesen" wrote
> For general-purpose circuits #14 can handle 15A, #12 can handle 20A, and
> #10 can take 30A.
That is before the 20% derate factor.
When a c'bkr is in a panel, it is derated by 20% to handle the panel heat
generated by adjacent c'bkrs..
Thus #14 can only handle 15*80%=12A on a continuous basis.
There ain't no free lunch.
Lew
Lew Hodgett wrote:
> BTW, Lew's rule for shop wiring:
>
> #12 AWG for all 1Pole(120V) circuits and #10AWG for all 2Pole(240V)
> circuits.
I agree that it makes sense to wire a shop with 20A circuits for
receptacles. Just gives a bit of leeway if you plug in a couple things
onto one circuit.
However, I think that wiring all the 240V circuits with #10 is overkill
given that it costs significantly more than #12. How many people have
5HP tools in their home shop? I have one 30A outlet for an electric
heater and a future welder. All the rest of my 240V outlets are 20A.
I do think it's a good idea for critical large items (compressor and
dust collector) get their own circuits. Most of the others (tablesaw,
planer, jointer, bandsaw) could realistically share a circuit or two in
a home shop since usually only one will be in use at any given time.
Chris
"Chris Friesen" wrote:
> However, I think that wiring all the 240V circuits with #10 is overkill
> given that it costs significantly more than #12.
Not really, think full boxes of wire, not cut lengths.
Standardize on one wire size, buy full boxes(spools) of wire and get a
better price.
Even if it cost 15-20% more up front, there will come a day
when.....................
Lew
Doug Miller wrote:
> In article <[email protected]>, "no
> spam" <[email protected]> wrote:
>
>> Personally, when it comes to wiring bigger IS better.
>
> Nonsense. Except on very long runs, bigger wire provides no
> advantages at all,
> and does provide significant disadvantages:
> a) higher cost
> b) greater difficulty in installation
> c) difficulty in finding compatible receptacles (for example, try
> finding a 15A rated receptacle that will accept AWG8 wire)
> d) the larger the wire, the fewer of them the Code allows you to put
> in a box.
Just curious.....aren't most electrical fires related to junctions,
switches, receptacles and things plugged into them? In other words aren't
strait wire runs the least problematic of any potential electrical fault as
well? Rod
"Doug Miller", self declared electrical genius wrote:
> +++++
>
> "When a c'bkr is in a panel, it is derated by 20% to handle the panel heat
> generated by adjacent c'bkrs.." -- nonsense. Circuit breakers are
*required*
> by Code to be placed in a panel or other similar fixture [Article 240.30]
and
> no derating is applied for doing so.
Name plate ratings of molded case thermal-magnetic c'bkrs are for bkrs in
free air.
As soon as the bkr is placed in an enclosure, detating applies.
Take your meds and go read your code book again, this time try to understand
what you read.
> +++++
>
> "#14 can only handle 15*80%=12A on a continuous basis." Correct, but
> incomplete and potentially misleading, as it omits the Code definition of
a
> continuous load: "where the maximum current is expected to continue for 3
> hours or more." [Article 100] This is *not* a usual, typical, normal
> condition.
Three (3) hours doesn't meet the definition of "continuous" in my world.
Lew
"Chris Friesen" <[email protected]> wrote in message
news:[email protected]...
> Leon wrote:
>
>> 10/3 and 12/3 are with ground. Also there are only 3 wires in those
>> cables.
>> 10/2 and 12/2 only have 2 wires.
>
> That's incorrect. The second number is the number of conductors. Ground
> isn't counted as a "conductor".
>
> Chris
No, I think that when the say "conductor", they mean insulated conductor.
You can (or could anyway) by 10/2 with no ground.
220 wiring needs two hot conductors, a center conductor (which may or may
not be at ground), and a ground wire.
Jim
since my first posting a few weeks ago I have contacted an electrician
who than decided not to show up. I than decided to do the wiring
myself and am happy to say that it is complete and inspection passed.
I would like to thank all posters who threw their 2 cents in.
Jim
On Fri, 10 Aug 2007 14:19:22 -0700, [email protected] wrote:
>In recent posts I have heard mention of 12/2 and 10/2 wire, as well as
>12/3 and 10/3 wire. What is the difference and what would you wire a
>new shop with?
>
>I assume the 12/2 and 10/2 mean with ground.? What is the extra wire
>in the 12/3 and 10/3 for? Is that for wiring 220V?
>
>Jim
In article <[email protected]>, "no spam" <[email protected]> wrote:
>
>>> Third, if you need to 'upsize' later its a lot easier to just put in a
>>> larger breaker than putting in new or more wire.
>>
>> If you wire for higher ampacity, then may as well install appropriately
>> sized breakers and outlets, etc., at the time. Otherwise, unless wasted
>> the extra money for the higher-rated outlets until that unforeseen maybe
>> never to happen time in the future, placing simply a larger breaker may be
>> fine for the wiring itself but not for the outlets, etc., ...
>
>True but I was thinking of being able to add more outlets to the same line.
>Example when I bought my last house there was one outlet along the wall were
>I wanted to put my entertainment center I had to use 2 power strips. No big
>deal there because nothing was drawing much power and very few of the items
>were on at any one time. But what if in the future things need more power?
>I'm guessing they will. Its a lot easier to put an outlet or two on an
>existing circuit than it is to run an entire new line from the breaker box.
Of course it is. But if you increase the breaker size past 20A, every single
one of your outlets turns into a Code violation.
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
[email protected] wrote:
> In recent posts I have heard mention of 12/2 and 10/2 wire, as well as
> 12/3 and 10/3 wire. What is the difference and what would you wire a
> new shop with?
>
> I assume the 12/2 and 10/2 mean with ground.? What is the extra wire
> in the 12/3 and 10/3 for? Is that for wiring 220V?
>
> Jim
Rules of thumb. #14 wire takes a 15 amp breaker
#12 wire takes a 20 amp breaker
Ordinary 120 Volt wall sockets are rated for 15 or 20 amps and will
accept #14 or #12 wire. I suppose it's possible to jam #10 wire under
the screws but I wouldn't do it myself. Based on this, I wire my branch
circuits with #12.
Connect black to brass, white to chrome.
Treat both sides of the AC line (black and white) as hot. Some other
electrician may have forgotten about black to brass and white to chrome
somewhere else in the building wiring.
Ground every piece of metal you can touch.
David Starr
Tom Veatch wrote in news:[email protected]:
*snip*
> Before anybody gets incensed, "ignorance" is the opposite of
> "knowledge", not the opposite of "intelligence" and is not an insult.
> None of us know all there is to know, so we are all ignorant of more
> things than we have knowledge of.
>
*snip*
I know something about everything. Sometimes I know that I don't know.
;-)
Puckdropper
--
Wise is the man who attempts to answer his question before asking it.
To email me directly, send a message to puckdropper (at) fastmail.fm
Tom Veatch wrote:
| Then I would say you've advanced to the 2nd level of knowledge on
| that particular topic.
|
| 1. Don't know that you don't know.
| 2. Know that you don't know.
| 3. Know that you know.
| 4. Don't know that you know.
This sounds remarkably like a former Secretary of Defense's
semi-coherent ramblings on Middle East intelligence...
--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/SC_Madison.html
"no spam" <[email protected]> wrote in
news:[email protected]:
*snip*
>
> Personally, when it comes to wiring bigger IS better. Even more so
> when it comes to a workshop. I'm looking at building a new home in a
> few years and if I can afford it I will 'over wire' the entire house
> for a couple of reasons. First, look around your house now and think
> about how it looked 10 years ago. How many more electrical items do
> you have now? How many more might we have in 10 more years?
>
*snip*
>
> Third, if you need to 'upsize' later its a lot easier to just put in a
> larger breaker than putting in new or more wire.
>
>
That was my theory with my LAN. When I was initially building it, I
decided to go with Cat 5 cable capable of 100 mbs, and only get a hub
capable of 10 mbs. When the prices came down on 100 mbs switches, all I
had to do was unplug one and plug in the new one.
Puckdropper
--
Wise is the man who attempts to answer his question before asking it.
To email me directly, send a message to puckdropper (at) fastmail.fm
On Tue, 14 Aug 2007 11:40:26 -0400, "Mike Marlow"
<[email protected]> wrote:
>
>"Bradford Chaucer" <[email protected]> wrote in message
>news:[email protected]...
>> 10 or 12 is the wire size, 2 or 3 the number of conductors. All Romex
>> type
>> cable has a ground which is not referenced as an "official: conductor.
>> 10/3
>> cable has 3 10awg power carrying conductors and a ground. The 3 conductors
>> are white (neutral) Black and Red (hots) and is used in balanced 240/120
>> volt circuits (120 from each hot to neutral, 240 across the hots) 10/2
>> has
>> a white and black and is used in 120volt circuits only.
>
>This is just patently incorrect. Perhaps it's a typo, but in matters like
>this good proof reading becomes essential. 10/2 is not used in 120v
>circuits only.
Actually, I'd be surprised if 10/2 was used in 120V circuits at all.
--
LRod
Master Woodbutcher and seasoned termite
Shamelessly whoring my website since 1999
http://www.woodbutcher.net
Proud participant of rec.woodworking since February, 1997
email addy de-spam-ified due to 1,000 spams per month.
If you can't figure out how to use it, I probably wouldn't
care to correspond with you anyway.
On Sat, 11 Aug 2007 22:33:45 -0400, "Mike Marlow"
<[email protected]> wrote:
>
>One who lacks knowledge on a topic is far better served by telling the
>electrician what functionality he wants and leaving the how-to's to the
>person most knowledgeable - the electrician. BTW, no - all electricians are
>not going to wire with 12/2 on 220 and 10/2 on 110. Just the opposite. And
>yes - for the most part, all electricians are going to wire the same way -
>based on the requirements of the circuit.
I won't argue against the point of specifying the desired
functionality to the electrician - that's just good sense. But I do
take a mild exception to the "better served" part. It's been said that
a "little knowledge is dangerous", but I firmly believe that ignorance
is even more dangerous.
Before anybody gets incensed, "ignorance" is the opposite of
"knowledge", not the opposite of "intelligence" and is not an insult.
None of us know all there is to know, so we are all ignorant of more
things than we have knowledge of.
I applaud the OP's question. Any attempt by a person to convert a
little ignorance into a little knowledge is a laudable pursuit.
Tom Veatch
Wichita, KS
USA
"John Starr" <[email protected]> wrote in message
news:[email protected]...
> You have always heard there are no stupid questions. Maybe the
> questions were asked for reference. To see what others had done when
> there shop was wired. I think it was a legitimate question asking the
> difference between the wires. If he is to have someone wire the shop
> are all electricians going to wire with 12/2 on 220 and 10/2 on 110?
> Knowledge is a good thing and being able to tell the electrician what
> you want can only make the shop that much better.
>
One who lacks knowledge on a topic is far better served by telling the
electrician what functionality he wants and leaving the how-to's to the
person most knowledgeable - the electrician. BTW, no - all electricians are
not going to wire with 12/2 on 220 and 10/2 on 110. Just the opposite. And
yes - for the most part, all electricians are going to wire the same way -
based on the requirements of the circuit.
--
-Mike-
[email protected]
In article <[email protected]>, dpb <[email protected]> wrote:
>I assume somebody must still make it, but out of curiousity I did a
>little looking -- lots of feeder and various other larger cable, but I
>couldn't find a single reference to 10/x or smaller Al. Smallest I
>found was #8.
Hmm. Thought I'd seen #10 not too long ago. But then, "not too long ago" is a
longer time period than it used to be, too. :-(
>
>I'm thinking w/ the Al-wiring scare there simply has been so little
>demand for ordinary circuit Al wiring it has become almost, if not, a
>thing of the past.
I imagine the biggest factor is this:
"Conductors normally used to carry current shall be of copper unless otherwise
provided in this Code." [2005 NEC, Article 110.5]
Exceptions include services and feeders, but not (as far as I can tell) branch
circuits.
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
"Jim" <[email protected]> wrote in message
news:[email protected]...
>
> "Chris Friesen" <[email protected]> wrote in message
> news:[email protected]...
>> Leon wrote:
>>
>>> 10/3 and 12/3 are with ground. Also there are only 3 wires in those
>>> cables.
>>> 10/2 and 12/2 only have 2 wires.
>>
>> That's incorrect. The second number is the number of conductors. Ground
>> isn't counted as a "conductor".
>>
>> Chris
> No, I think that when the say "conductor", they mean insulated conductor.
> You can (or could anyway) by 10/2 with no ground.
> 220 wiring needs two hot conductors, a center conductor (which may or may
> not be at ground), and a ground wire.
No. 220 works just fine with two conductors and ground. You only need
neutral if you will be taking 120v loads off of one of the legs.
--
-Mike-
[email protected]
<Tom Veatch> wrote in message
news:[email protected]...
>
> I applaud the OP's question. Any attempt by a person to convert a
> little ignorance into a little knowledge is a laudable pursuit.
>
Oh, I applaud anyone's interest in gaining new knowledge. That however, is
not the point of Robert's and other comments about seeking qualified help on
some things when one's level of knowledge is so low. And my follow on
comment in response to you was simply that one would be foolish to expect
that a couple of posts in a woodworking usenet newsgroup is make one capable
of directing an electrician in how to perform a task. That would be a
dangerous amount of knowledge.
--
-Mike-
[email protected]
"Leon" <[email protected]> wrote in message
news:wS4vi.159$%[email protected]...
>
> <[email protected]> wrote in message
> news:[email protected]...
>> In recent posts I have heard mention of 12/2 and 10/2 wire, as well as
>> 12/3 and 10/3 wire. What is the difference and what would you wire a
>> new shop with?
>>
>> I assume the 12/2 and 10/2 mean with ground.? What is the extra wire
>> in the 12/3 and 10/3 for? Is that for wiring 220V?
>>
>> Jim
>
> 10/3 and 12/3 are with ground. Also there are only 3 wires in those
> cables.
>
> 10/2 and 12/2 only have 2 wires.
>
No, no. X/2 means X conductors *plus* a ground. Two colored insulated
conductors, plus a bare ground conductor. Typically today, it's difficult
to find wire without a ground wrapped in it. In the old days it was easy to
find that and the terminology made accurate sense, but these days ground is
always there. So, the actual wire count in X/2 is three.
X/3 also indicates the number of conductors not counting ground, so there
are three colored conductors, *plus* ground. Useful for such things as
three way switches, etc. Likewise, the actual conductor count in X/3 is
four.
--
-Mike-
[email protected]
"Leon" <[email protected]> wrote in message
news:[email protected]...
>
> YES! My head was not in the right place, he did say wiring the shop. I
> was thinking an extension cord, not Romex. My extension cord is a 10/3
> with 3 insulated wires.
>
Oh hell - we all do that from time to time. It's what makes us loveable...
--
-Mike-
[email protected]
On 8/10/07 6:47 PM, "Chris Friesen" <[email protected]> wrote:
> Lew Hodgett wrote:
>
> I agree that it makes sense to wire a shop with 20A circuits for
> receptacles. Just gives a bit of leeway if you plug in a couple things
> onto one circuit.
Start off by looking at the power requirements of the tools that you are
likely to use. With the exception of a dust collector, you probably won't
run any of your tools at the same time.
20A circuits for standard 110v outlets is about right for a shop with
typical hand held power tools.
>
> However, I think that wiring all the 240V circuits with #10 is overkill
> given that it costs significantly more than #12. How many people have
> 5HP tools in their home shop? I have one 30A outlet for an electric
> heater and a future welder. All the rest of my 240V outlets are 20A.
>
> I do think it's a good idea for critical large items (compressor and
> dust collector) get their own circuits. Most of the others (tablesaw,
> planer, jointer, bandsaw) could realistically share a circuit or two in
> a home shop since usually only one will be in use at any given time.
Some other suggestions:
Put your lights on a separate circuit. It's a pain when you pop a breaker
and the lights go out.
If you have large stationery tools, put in a dedicated circuit for each one.
Put in lots of outlet. One for every three to four feet of wall at a
minimum.
Think about where you might put benches, etc. It helps to have plenty of
outlets nearby, including some above the bench. I put all the outlets in my
shop four feet above the floor.
On 8/10/07 7:55 PM, "Chris Friesen" <[email protected]> wrote:
> Lew Hodgett wrote:
>
>> Even if it cost 15-20% more up front, there will come a day
>> when.....................
>
> When I was shopping the price difference was a lot more than that, even
> by the box/spool. Closer to 50-70%. I couldn't justify it.
That's just the wire - right? What was the percentage of the total
materials? And if you pay an electrician to install it, the wire cost is
insignificant.
On 8/11/07 1:34 PM, "[email protected]" <[email protected]> wrote:
> Mentioned are 15 and 20 amp 110 circuits.
>
> Is there any reason to have 15 amp circuits?
>
> Wire everything with 20 amp outlets and be done with it.
>
I put all my outlets on 20 Amp breakers with 12g. Wiring, but I used 15 Amp
circuits for the lighting.
"Mike Marlow" <[email protected]> wrote in message
news:[email protected]...
>
>>
>
> It's unusual to find ground insulated in a romex type wire. Are you quite
> certain of this Leon?
Quite sure however this is not Romex, it is a some what flexible extension
cord that I have made up. I did not picture Romex when answering the
question. Doh!
"Chris Friesen" <[email protected]> wrote in message
news:[email protected]...
> Leon wrote:
>
>> 10/3 and 12/3 are with ground. Also there are only 3 wires in those
>> cables.
>> 10/2 and 12/2 only have 2 wires.
>
> That's incorrect. The second number is the number of conductors. Ground
> isn't counted as a "conductor".
>
> Chris..
All of the wires in my 10/3 are insulated.
<[email protected]> wrote in message
news:[email protected]...
> In recent posts I have heard mention of 12/2 and 10/2 wire, as well as
> 12/3 and 10/3 wire. What is the difference and what would you wire a
> new shop with?
>
> I assume the 12/2 and 10/2 mean with ground.? What is the extra wire
> in the 12/3 and 10/3 for? Is that for wiring 220V?
>
As another person responded, ground is inferred, so 12/2 is
white/black/bare. 12/3 is white/black/red/bare, with the red being the
other hot side for wiring 220.
In article <[email protected]>, "no spam" <[email protected]> wrote:
>Personally, when it comes to wiring bigger IS better.
Nonsense. Except on very long runs, bigger wire provides no advantages at all,
and does provide significant disadvantages:
a) higher cost
b) greater difficulty in installation
c) difficulty in finding compatible receptacles (for example, try finding a
15A rated receptacle that will accept AWG8 wire)
d) the larger the wire, the fewer of them the Code allows you to put in a box.
>Even more so when it
>comes to a workshop. I'm looking at building a new home in a few years and
>if I can afford it I will 'over wire' the entire house for a couple of
>reasons. First, look around your house now and think about how it looked 10
>years ago. How many more electrical items do you have now? How many more
>might we have in 10 more years?
This purpose is achieved much more easily, and at considerably lower cost, by
keeping the wire size the same and increasing the number of circuits.
>
>Second, its much more difficult to have an electrical fire if you wire a 20
>amp breaker with wire that will carry 40 amps or so.
Nonsense again. The risk of electrical fire is not significantly greater using
AWG12 wire on a 20A breaker, compared to using AWG8 -- and in fact, you'd
probably be creating a substantial risk of fire by attempting to connect a
standard receptacle to conductors that are too large to fit under the screw
terminals. Sure, you can pigtail the connections -- let me know when you're
getting ready to wire up those receptacles. I want to come watch you stuff
the wires back in the box; I could use a few laughs.
And then I'll phone the local electrical inspector. "Wire that will carry 40
amps or so" is AWG8 or larger. You might want to consult Table 314.16(A) in
the NEC to see how many AWG8 conductors the Code allows you to put in a
standard device box. (Hint: except with the largest device box available, it's
not enough to supply a receptacle -- and forget about feeding through to
another receptacle, or using anything larger than AWG8.)
>Third, if you need to 'upsize' later its a lot easier to just put in a
>larger breaker than putting in new or more wire.
Nonsense yet again. What, exactly, do you plan to "upsize" to, anyway? It's a
Code violation to put a 20A receptacle on a circuit protected by anything but
a 20A breaker. The larger wire serves no purpose at all.
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
In article <[email protected]>, duckecho@gmail-dot-com wrote:
>On Tue, 14 Aug 2007 11:40:26 -0400, "Mike Marlow"
><[email protected]> wrote:
>
>>
>>"Bradford Chaucer" <[email protected]> wrote in message
>>news:[email protected]...
>>> 10 or 12 is the wire size, 2 or 3 the number of conductors. All Romex
>>> type
>>> cable has a ground which is not referenced as an "official: conductor.
>>> 10/3
>>> cable has 3 10awg power carrying conductors and a ground. The 3 conductors
>>> are white (neutral) Black and Red (hots) and is used in balanced 240/120
>>> volt circuits (120 from each hot to neutral, 240 across the hots) 10/2
>>> has
>>> a white and black and is used in 120volt circuits only.
>>
>>This is just patently incorrect. Perhaps it's a typo, but in matters like
>>this good proof reading becomes essential. 10/2 is not used in 120v
>>circuits only.
>
>Actually, I'd be surprised if 10/2 was used in 120V circuits at all.
There would be a few rare cases, such as
- very long run on a 20A circuit, where voltage drop is a legitimate concern
- 30A circuit supplying, for example, fixed space heating equipment
but I'm sure that its most common use, by far, is in 240V circuits.
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
"LRod" wrote in message
> Yeah, right. My uncle did that when he built his house back in the
> '60s. He ran 12 ga to every single device in the house--receptacles,
> switches, lights. At the tiime I thought it was a good idea--after
> all, it's only one size up, right?
Your uncle would be right at home in most of the municipalities around here
... along with the requirement for 5/8" drywall, the minimum wire size
allowed here for _any_ circuit, lights included, is 12ga.
--
www.e-woodshop.net
Last update: 8/8/07
KarlC@ (the obvious)
"Mike Marlow" <[email protected]> wrote in message
news:[email protected]...
>>
>
> No, no. X/2 means X conductors *plus* a ground. Two colored insulated
> conductors, plus a bare ground conductor. Typically today, it's difficult
> to find wire without a ground wrapped in it. In the old days it was easy
> to find that and the terminology made accurate sense, but these days
> ground is always there. So, the actual wire count in X/2 is three.
>
> X/3 also indicates the number of conductors not counting ground, so there
> are three colored conductors, *plus* ground. Useful for such things as
> three way switches, etc. Likewise, the actual conductor count in X/3 is
> four.
YES! My head was not in the right place, he did say wiring the shop. I
was thinking an extension cord, not Romex. My extension cord is a 10/3 with
3 insulated wires.
In article <[email protected]>, [email protected] wrote:
>10 or 12 is the wire size, 2 or 3 the number of conductors. All Romex type
>cable has a ground which is not referenced as an "official: conductor. 10/3
>cable has 3 10awg power carrying conductors and a ground. The 3 conductors
>are white (neutral) Black and Red (hots) and is used in balanced 240/120
>volt circuits (120 from each hot to neutral, 240 across the hots)
All correct up to this point, but now you go astray:
>10/2 has a white and black and is used in 120volt circuits only.
Completely incorrect. Since a 240V circuit has no neutral conductor, only
two hots and a ground, 10/2 with ground is perfectly fine for use in 240V
circuits up to 30A. Three-conductor cable (such as 10/3) is needed for a 240V
circuit only if there are also 120V loads on the circuit; an example of this
would be an electric dryer, which has 240V heating elements and (typically) a
120V motor. The 240V motors which are typically found in woodworking tools
have no neutral, only two hots, and will get along just fine on circuits wired
with two-conductor cable.
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
Puckdropper <[email protected]> wrote in
news:[email protected]:
> "no spam" <[email protected]> wrote in
> news:[email protected]:
>
> *snip*
>
>>
>> Personally, when it comes to wiring bigger IS better. Even more so
>> when it comes to a workshop. I'm looking at building a new home in a
>> few years and if I can afford it I will 'over wire' the entire house
>> for a couple of reasons. First, look around your house now and think
>> about how it looked 10 years ago. How many more electrical items do
>> you have now? How many more might we have in 10 more years?
>>
>
> *snip*
>
>>
>> Third, if you need to 'upsize' later its a lot easier to just put in
>> a larger breaker than putting in new or more wire.
>>
>>
>
> That was my theory with my LAN. When I was initially building it, I
> decided to go with Cat 5 cable capable of 100 mbs, and only get a hub
> capable of 10 mbs. When the prices came down on 100 mbs switches, all
> I had to do was unplug one and plug in the new one.
>
> Puckdropper
An entirely different kettle of fish. The wire you used is part of the
standard for both speeds, and maybe others, and works pretty easily for
the setup you describe.
Which is pretty much exactly what was discussed back in the early to
mid-90's when all of this started to come together...
Patriarch,
who did the same thing, really...
In article <[email protected]>, duckecho@gmail-dot-com wrote:
>On Fri, 10 Aug 2007 14:19:22 -0700, [email protected] wrote:
>
>[electrical question snipped]
>there are about three or four posters here whose electrical
>information you can trust. Probably at the top of the list is Doug
>Miller. View anyone else's answers with suspicion. I'm surprised he
>hasn't posted already. I'm sure he will, however. He can cite the NEC
>chapter and verse. Hardly anyone else here can.
Thanks for the endorsement, Rod. I'll try to clarify a few things that seem to
need it, and correct a few things that definitely need it. Would've jumped in
earlier, but I was out of town for the weekend.
"You are only allowed to put a maximum of 12 lights on one 15 amp circuit" --
nonsense. There is no such limitation in the Code for residential
installations. The frequently-claimed limitation on the number of outlets on a
circuit doesn't exist either, for residential installations.
+++++
The discussion so far of the number of conductors in a nn/2 or nn/3 cable has
been only partially correct. Nobody has yet given the complete answer, which
is:
1) In cable intended and approved for use in premises wiring -- NM ("Romex"),
BX, AC, UF, etc. -- the number following the slash *does*not* include
equipment grounding conductors which *may*or*may*not* be present. Thus 12/3
Romex cable contains three insulated 12-gauge conductors (black, red, and
white) and usually contains a fourth conductor, either bare or with green
insulation.
2) In cable intended and approved for use in cord-and-plug connections, the
number following the slash indicates the number of conductors in the cable -
period - without regard to their use. Thus 12/3 Type SJ cable contains three
insulated 12-gauge conductors, usually black, white, and green, and that's
all.
3) The above two categories are mutually exclusive.
+++++
"When a c'bkr is in a panel, it is derated by 20% to handle the panel heat
generated by adjacent c'bkrs.." -- nonsense. Circuit breakers are *required*
by Code to be placed in a panel or other similar fixture [Article 240.30] and
no derating is applied for doing so.
+++++
"#14 can only handle 15*80%=12A on a continuous basis." Correct, but
incomplete and potentially misleading, as it omits the Code definition of a
continuous load: "where the maximum current is expected to continue for 3
hours or more." [Article 100] This is *not* a usual, typical, normal
condition.
+++++
"Either 12/2 or 12/3 will contain a green ground conductor." -- nonsense.
In NM cable (the type used most frequently in residential construction) the
grounding conductor is uninsulated.
+++++
"12/2 would be used for a 240V/1Ph/60Hz service." Correct, as long as it's a
15A or 20A circuit. Higher-current circuits require larger wire.
+++++
Some erroneous statements were made about how 240V circuits need to be wired,
but they've already been adequately corrected by others, and I won't bother to
rehash that.
>
>By the way, just to throw a monkey wrench in the works for all the
>oh-so-sure posters about the number of conductors in a cable--it
>wasn't so long ago ( in my lifetime and I can personally attest to
>it), that if you wanted a ground wire with your Romex (trade name for
>NMC or non metallic cable) you had to say "with ground." It was not
>implied.
I can attest to that as well.
> Granted that's no longer the case, but it does illustrate how
>gray an answer can sometimes be. Could be important is some old work.
>
>My advice (and you can take this one to the bank) is don't be
>satisfied that you have all the information you need based on the
>answers you've received so far.
This is one of those topics that's always sure to generate a lot of traffic,
including a large number of confidently delivered but incorrect answers.
:-)
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
In article <[email protected]>, "no spam" <[email protected]> wrote:
>I'm not sure what you mean. Are you saying that its tough to have three 10
>ga wires coming into one box or are you saying its hard to work 10 ga wire?
Both.
10ga wire is *much* harder to work with than 12ga. And Code doesn't allow as
many conductors in a box.
>Other than 3 way lights why would you have that many wires and a swith or
>outlet in one box?
It's common practice for receptacle boxes to be daisy-chained, with each box
but the last on the run having two cables, power in and power out. That means
four conductors. For the purposes of calculating the required space in the
box, Code requires you to add one for the equipment grounding conductors, two
for the receptacle, and one for each cable clamp. That's eight in all -- times
2.25 cu in for 12ga conductors, or 2.50 cu in for 10ga. And that makes the
difference between being Code-compliant (with 12ga conductors in the largest
standard device box available) and being a violation with 10ga conductors in
*any* single-gang device box.
>I've put in a several 220VAC outlets into regular boxs
>(the kind you use to power portable 220 heaters) using 10ga copper. Stiff
>but not that bad.
Now try doing an entire living room's worth of receptacles and switches, say
eight or ten devices. How do your hands feel after that?
>>>Second, its much more difficult to have an electrical fire if you wire a 20
>>>amp breaker with wire that will carry 40 amps or so.
>>
>> You can't be serious. It's not nearly as difficult as finding a 15 or
>> 20 amp receptacle into which you can stuff that 8 gauge wire.
>
>Only slightly. Try 15 amp breaker with 20 amp wire. Of course the weakness
>I have found in the entire system is the outlet itself. Wires work loose or
>bad contacts cause arcing which cause fires.
Exactly -- the weakness is in the outlet, and in the connections to it. There
is no practical benefit from using larger wire.
>
>
>>>Third, if you need to 'upsize' later its a lot easier to just put in a
>>>larger breaker than putting in new or more wire.
>>
>> Dumb idea #3. The difference in cost between a 20A breaker and 30A
>> breaker is negligible (they're virtually the same in the Square D QO
>> line). If you really were commited to running 10 gauge wire throughout
>> the house (ignoring, for the moment, the difficulty in working it and
>> the utter lack of need for it) why would you not go ahead and put 30A
>> breakers in?
>
>The house is still at least 3 years from being started so I might if there
>isn't that much difference in price and the code Nazis allow it I probably
>will. After dealing with them just trying to put in a trailer I hate to
>think about the rules they have for wiring a new house.
15A or 20A rated receptacles on a circuit with a 30A (or larger) breaker is a
violation.
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
"Leon" <[email protected]> wrote in message
news:[email protected]...
>
> "Chris Friesen" <[email protected]> wrote in message
> news:[email protected]...
>> Leon wrote:
>>
>>> 10/3 and 12/3 are with ground. Also there are only 3 wires in those
>>> cables.
>>> 10/2 and 12/2 only have 2 wires.
>>
>> That's incorrect. The second number is the number of conductors. Ground
>> isn't counted as a "conductor".
>>
>> Chris..
>
> All of the wires in my 10/3 are insulated.
>
It's unusual to find ground insulated in a romex type wire. Are you quite
certain of this Leon?
--
-Mike-
[email protected]
> Speaking of useless answers. I went to some trade show years ago. I
> got a tote bag that might have said Copper is Proper. I cannot find
> the tote bag to see if that was the logo. Two points were made in the
> handout and it was geared towards commercial electricians. Well maybe
> one point. Copper flows electricity better than aluminum. 12 guage can
> be less expensive over the life of a building versus 14 guage due to
> lower power losses with the bigger wire. Equipment can run better with
> lower voltage drops.
I know copper wire has many advantages over AL wire but I have a question or
two.
First off why is almost all the 'big' wire AL? When I started service here
I was required to buy AL wire to connect the meter to the breaker box on the
pole and to connect that box to the breaker box in the trailer.
Also can you even buy 'small' AL wire, e.g. 10 ga? If so is it that much
cheaper than Cu?
Would anyone here use AL wire for anything?
>> [electrical question snipped]
>>
>> You have just been introduced to the hazard of soliciting specialized
>> advice on the internet.
>
> I'll take that one step further. If a guy has to ask the difference
> between 10/2, 10/3. 12/2 etc... WTF is he doing wiring his shop?
I wired my entire place but almost made the same mistake. I almost bought
10/3 because I wanted to have a ground wire.
> For chrissakes, call somebody who knows and who has the certification
> and insurance!!
>
> And GET A FARKING PERMIT!!
Yes buy all means let's make sure the government gets its pound of flesh. I
paid all the money and got all the permits and did all the work myself. My
final inspection consisted of a guy showing up and sitting in his truck
while we talked about the old PBY flying boat. After about 10 minutes he
signed my paperwork and drove off to do his next inspection.
> (Yes, yes, I know, I know... there are many here who have the
> knowledge and confidence to do that kind of work themselves, but when
> questions indicate a complete and total ignorance of the topic at
> hand.........)
A permit ain't going to help that. For onething people like that are the
very ones who don't get permits.
On Fri, 10 Aug 2007 21:26:04 -0500, "Jim" <[email protected]> wrote:
...
>220 wiring needs two hot conductors, a center conductor (which may or may
>not be at ground), and a ground wire.
...
You only need the "center" (neutral) conductor if you are going to be
taking 110 off the circuit as well as 220. In that case, you need a 4
wire (3 + ground) cable. If the circuit is dedicated to 220v service
only, then the neutral is unnecessary and three wire ( 2 + ground)
cable is sufficient.
Haven't read all the other posts, so don't know if anyone replied to
the OP relative to the gauge. But, if not, then the "10", "12", "14",
etc in the designation is the wire gauge or size. Typical use is 14
gauge for circuits not to exceed 15 amps, 12 gauge for 20 amp
circuits, 10 gauge for 30 amp, etc. Circuit amperage is limited by the
size of the breaker the wire is connected to.
I'm not an electrician and only have nodding acquaintance with NEC
requirements. However, I'd recommend that if you (the OP) is wiring a
shop, use 14 gauge only for dedicated lighting circuits and 12 gauge
for all the 110v branch circuits. Its a little more expensive but its
a one time expense and with the proper receptacles, you've got 20 amps
available at the wall sockets.
Tom Veatch
Wichita, KS
USA
>> You have always heard there are no stupid questions. Maybe the
>> questions were asked for reference. To see what others had done when
>> there shop was wired. I think it was a legitimate question asking the
>> difference between the wires. If he is to have someone wire the shop
>> are all electricians going to wire with 12/2 on 220 and 10/2 on 110?
>> Knowledge is a good thing and being able to tell the electrician what
>> you want can only make the shop that much better.
>>
>
> One who lacks knowledge on a topic is far better served by telling the
> electrician what functionality he wants and leaving the how-to's to the
> person most knowledgeable - the electrician. BTW, no - all electricians
> are not going to wire with 12/2 on 220 and 10/2 on 110. Just the
> opposite. And yes - for the most part, all electricians are going to wire
> the same way - based on the requirements of the circuit.
A couple of more points. 1) The more you now about things the easier it is
to calculate your building cost.
2) If you have people bid on a project it helps to know just what they are
planning on using. If Joe's Power bid is lower than Bill's Power its nice
to know that one reason is Joe's is planning on using smaller wire.
Personally, when it comes to wiring bigger IS better. Even more so when it
comes to a workshop. I'm looking at building a new home in a few years and
if I can afford it I will 'over wire' the entire house for a couple of
reasons. First, look around your house now and think about how it looked 10
years ago. How many more electrical items do you have now? How many more
might we have in 10 more years?
Second, its much more difficult to have an electrical fire if you wire a 20
amp breaker with wire that will carry 40 amps or so.
Third, if you need to 'upsize' later its a lot easier to just put in a
larger breaker than putting in new or more wire.
"Bradford Chaucer" <[email protected]> wrote in message
news:[email protected]...
> 10 or 12 is the wire size, 2 or 3 the number of conductors. All Romex
> type
> cable has a ground which is not referenced as an "official: conductor.
> 10/3
> cable has 3 10awg power carrying conductors and a ground. The 3 conductors
> are white (neutral) Black and Red (hots) and is used in balanced 240/120
> volt circuits (120 from each hot to neutral, 240 across the hots) 10/2
> has
> a white and black and is used in 120volt circuits only.
This is just patently incorrect. Perhaps it's a typo, but in matters like
this good proof reading becomes essential. 10/2 is not used in 120v
circuits only.
--
-Mike-
[email protected]
In article <[email protected]>, "no spam" <[email protected]> wrote:
>I know copper wire has many advantages over AL wire but I have a question or
>two.
>
>First off why is almost all the 'big' wire AL?
Lightweight, and less expensive.
>When I started service here
>I was required to buy AL wire to connect the meter to the breaker box on the
>pole and to connect that box to the breaker box in the trailer.
Required? Really? That's unusual.
>
>Also can you even buy 'small' AL wire, e.g. 10 ga?
Yes.
> If so is it that much cheaper than Cu?
Yes.
>
>Would anyone here use AL wire for anything?
Other than as a service entrance, no, not if I can help it.
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
no spam wrote:
>> Speaking of useless answers. I went to some trade show years ago. I
>> got a tote bag that might have said Copper is Proper. I cannot find
>> the tote bag to see if that was the logo. Two points were made in the
>> handout and it was geared towards commercial electricians. Well maybe
>> one point. Copper flows electricity better than aluminum. 12 guage can
>> be less expensive over the life of a building versus 14 guage due to
>> lower power losses with the bigger wire. Equipment can run better with
>> lower voltage drops.
>
> I know copper wire has many advantages over AL wire but I have a question or
> two.
>
> First off why is almost all the 'big' wire AL? When I started service here
> I was required to buy AL wire to connect the meter to the breaker box on the
> pole and to connect that box to the breaker box in the trailer.
>
> Also can you even buy 'small' AL wire, e.g. 10 ga? If so is it that much
> cheaper than Cu?
>
> Would anyone here use AL wire for anything?
Cost -- compare the price for large diameter Cu vis a vis Al and you'll
see they "why"...
It would be unusual to require Al, most will accept either as most
terminations these days are Cu/Al compatible. If the service gear was
rated for Al only, then it would make sense.
Another reason for Al is that it bends more easily so for larger sizes
it is easier to handle.
Al for service entrance, feeders, etc., sure...
I would expect a very high fraction or more of those "here" have Al in
their own residences in at least those applications.
--
no spam wrote:
...
> Third, if you need to 'upsize' later its a lot easier to just put in a
> larger breaker than putting in new or more wire.
If you wire for higher ampacity, then may as well install appropriately
sized breakers and outlets, etc., at the time. Otherwise, unless wasted
the extra money for the higher-rated outlets until that unforeseen maybe
never to happen time in the future, placing simply a larger breaker may
be fine for the wiring itself but not for the outlets, etc., ...
--
Doug Miller wrote:
> In article <[email protected]>, "no
spam" <[email protected]> wrote:
>
...
>> Also can you even buy 'small' AL wire, e.g. 10 ga?
>
> Yes.
>
>> If so is it that much cheaper than Cu?
>
> Yes.
...
I assume somebody must still make it, but out of curiousity I did a
little looking -- lots of feeder and various other larger cable, but I
couldn't find a single reference to 10/x or smaller Al. Smallest I
found was #8.
I'm thinking w/ the Al-wiring scare there simply has been so little
demand for ordinary circuit Al wiring it has become almost, if not, a
thing of the past.
I'm not sure for the smaller gauges the cost differential would be that
great, but maybe, but couldn't find any to try to do a comparison on...
--
Doug Miller wrote:
> In article <[email protected]>, dpb <[email protected]> wrote:
>
>> I assume somebody must still make it, but out of curiousity I did a
>> little looking -- lots of feeder and various other larger cable, but I
>> couldn't find a single reference to 10/x or smaller Al. Smallest I
>> found was #8.
>
> Hmm. Thought I'd seen #10 not too long ago. But then, "not too long ago" is a
> longer time period than it used to be, too. :-(
>> I'm thinking w/ the Al-wiring scare there simply has been so little
>> demand for ordinary circuit Al wiring it has become almost, if not, a
>> thing of the past.
>
> I imagine the biggest factor is this:
>
> "Conductors normally used to carry current shall be of copper unless otherwise
> provided in this Code." [2005 NEC, Article 110.5]
>
> Exceptions include services and feeders, but not (as far as I can tell) branch
> circuits.
I started to say I thought the Code _might_ have removed AL from branch
circuit use, but wasn't sure enough to say so (and didn't feel like
digging through to find out for sure).
That pp would certainly put a crimp in the market, wouldn't it? :)
So, at least for all practical purposes, the answer to the question of
is AL in smaller sizes (for electrical wiring purposes) available is "No"...
--
no spam wrote:
> "dpb" <[email protected]> wrote in message news:[email protected]...
>> no spam wrote:
>>>> Speaking of useless answers. I went to some trade show years ago. I
>>>> got a tote bag that might have said Copper is Proper. I cannot find
>>>> the tote bag to see if that was the logo. Two points were made in the
>>>> handout and it was geared towards commercial electricians. Well maybe
>>>> one point. Copper flows electricity better than aluminum. 12 guage can
>>>> be less expensive over the life of a building versus 14 guage due to
>>>> lower power losses with the bigger wire. Equipment can run better with
>>>> lower voltage drops.
>>> I know copper wire has many advantages over AL wire but I have a question
>>> or two.
>>>
>>> First off why is almost all the 'big' wire AL? When I started service
>>> here I was required to buy AL wire to connect the meter to the breaker
>>> box on the pole and to connect that box to the breaker box in the
>>> trailer.
>>>
>>> Also can you even buy 'small' AL wire, e.g. 10 ga? If so is it that much
>>> cheaper than Cu?
>>>
>>> Would anyone here use AL wire for anything?
>> Cost -- compare the price for large diameter Cu vis a vis Al and you'll
>> see they "why"...
>
> IIRC, you can use a smaller Cu wire.
But the comparison of the required Cu to that for Al for the same
current rating still favors Al in a sizable ratio.
>
>> It would be unusual to require Al, most will accept either as most
>> terminations these days are Cu/Al compatible. If the service gear was
>> rated for Al only, then it would make sense.
>
> I just know what the permit people told me. I guess you can't buy a Cu
> rated meter box.
I'm sure they were simply telling you to do common practice. Al is the
de facto standard for feeder/service use.
>
>> I would expect a very high fraction or more of those "here" have Al in
>> their own residences in at least those applications.
>
> I missed a word. It should read: Would anyone here use AL wire for anything
> else? That is would anyone here use AL wire from the breaker box to the
> outlets.
See Doug's response -- w/ NEC 2005 at least it isn't allowed.
--
Just a quick note about the progress of my garage. Since the first
post I have contacted an electrician, who decided not to show up. I
thus decided to do the wiring myselft. With the advice from this post
the wiring is finished and passed inspection. I want to thank all who
have thrown their 2 cents in helped me accomplish this part of my
project.
Thank you.
Jim
On Fri, 10 Aug 2007 14:19:22 -0700, [email protected] wrote:
>In recent posts I have heard mention of 12/2 and 10/2 wire, as well as
>12/3 and 10/3 wire. What is the difference and what would you wire a
>new shop with?
>
>I assume the 12/2 and 10/2 mean with ground.? What is the extra wire
>in the 12/3 and 10/3 for? Is that for wiring 220V?
>
>Jim
Speaking of useless answers. I went to some trade show years ago. I
got a tote bag that might have said Copper is Proper. I cannot find
the tote bag to see if that was the logo. Two points were made in the
handout and it was geared towards commercial electricians. Well maybe
one point. Copper flows electricity better than aluminum. 12 guage can
be less expensive over the life of a building versus 14 guage due to
lower power losses with the bigger wire. Equipment can run better with
lower voltage drops.
http://www.engineeringtoolbox.com/wire-gauges-d_419.html
http://www.jlmwholesale.com/images/WIREGAUGE.pdf
Another anecdote which might be worthless. I have a friend who is
certified in a lot of welding techniques. He has worked in power
plants, oil rigs, made non destructive weld samples and seems to have
a good bit of experience. He occasionally uses the small portable mig
welder like I have in the garage. He has found that the little 120
volt welder does better with 10 guage service wire than it does with
12 guage service wire. I don't know how long the wire runs were when
he was doing this experimenting but it reinforces the voltage drop.
His eyes and skill with welds are better than my hack welds.
On Sat, 11 Aug 2007 04:51:37 +0000, LRod <[email protected]>
wrote:
>On Fri, 10 Aug 2007 14:19:22 -0700, [email protected] wrote:
>
>[electrical question snipped]
>
>You have just been introduced to the hazard of soliciting specialized
>advice on the internet. In the gaggle of answers so far, you have
>gotten some good information, some incorrectly applied information,
>some information given with good intentions but poorly stated, and
>some plain incorrect information. You've even had a couple of
>responses telling other responders that they are incorrect.
>
>The big problem is, how do you know which is which? Unless you know
>the players, you can't. My drivel can look just as authoritative as
>anyone else's to someone relatively new to the Wreck. The fact is,
>there are about three or four posters here whose electrical
>information you can trust. Probably at the top of the list is Doug
>Miller. View anyone else's answers with suspicion. I'm surprised he
>hasn't posted already. I'm sure he will, however. He can cite the NEC
>chapter and verse. Hardly anyone else here can.
>
>By the way, just to throw a monkey wrench in the works for all the
>oh-so-sure posters about the number of conductors in a cable--it
>wasn't so long ago ( in my lifetime and I can personally attest to
>it), that if you wanted a ground wire with your Romex (trade name for
>NMC or non metallic cable) you had to say "with ground." It was not
>implied. Granted that's no longer the case, but it does illustrate how
>gray an answer can sometimes be. Could be important is some old work.
>
>My advice (and you can take this one to the bank) is don't be
>satisfied that you have all the information you need based on the
>answers you've received so far.
In article <[email protected]>, Mike M <[email protected]> wrote:
>#12 thhn cu wire is actually rated for about 35 amps.
30A, actually.
>The
>restriction to 20 amps is mainly based on the rating of the terminal
>on the CB.
That's part of it, but not the only reason. 10, 12, and 14 gauge wires are the
sizes most commonly used in residential circuits. The allowable overcurrent
protection is set by the Code at a value significantly under the actual
ampacity of the wires to reduce the risk of fire from overloading a circuit.
>You may use the higher ampacity ratings before taking your
>derating but still can't have over a 20 amp breaker.
Which means that the higher ampacity ratings are, for all practical purposes,
irrelevant. :-)
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
On Sat, 11 Aug 2007 12:41:38 GMT, Jim Behning
<[email protected]> wrote:
|Speaking of useless answers. I went to some trade show years ago. I
|got a tote bag that might have said Copper is Proper. I cannot find
|the tote bag to see if that was the logo. Two points were made in the
|handout and it was geared towards commercial electricians. Well maybe
|one point. Copper flows electricity better than aluminum. 12 guage can
|be less expensive over the life of a building versus 14 guage due to
|lower power losses with the bigger wire. Equipment can run better with
|lower voltage drops.
|http://www.engineeringtoolbox.com/wire-gauges-d_419.html
|http://www.jlmwholesale.com/images/WIREGAUGE.pdf
|
|Another anecdote which might be worthless. I have a friend who is
|certified in a lot of welding techniques. He has worked in power
|plants, oil rigs, made non destructive weld samples and seems to have
|a good bit of experience. He occasionally uses the small portable mig
|welder like I have in the garage. He has found that the little 120
|volt welder does better with 10 guage service wire than it does with
|12 guage service wire. I don't know how long the wire runs were when
|he was doing this experimenting but it reinforces the voltage drop.
|His eyes and skill with welds are better than my hack welds.
First of all, it's "gauge."
You don't need wire tables if you can remember that the resistance of
a round copper conductor is given by:
DC resistance ( Ohm/1000' at 20 C.) = 10 ^ (0.1 * AWG - 1)
where AWG is American Wire Gauge.
The resistivity of aluminum is approx 1.52 times copper.
So for a 20A run using 12 AWG, 100' long (200' of wire) the copper
loss is ~45 W.
For the same run in aluminum the loss is ~69 W.
The difference in efficiency (power delivered to load / power into
wire) is 98.1% vs. 97.1%.
Is this somthing to get excited about?
"dpb" <[email protected]> wrote in message news:[email protected]...
> no spam wrote:
>>> Speaking of useless answers. I went to some trade show years ago. I
>>> got a tote bag that might have said Copper is Proper. I cannot find
>>> the tote bag to see if that was the logo. Two points were made in the
>>> handout and it was geared towards commercial electricians. Well maybe
>>> one point. Copper flows electricity better than aluminum. 12 guage can
>>> be less expensive over the life of a building versus 14 guage due to
>>> lower power losses with the bigger wire. Equipment can run better with
>>> lower voltage drops.
>>
>> I know copper wire has many advantages over AL wire but I have a question
>> or two.
>>
>> First off why is almost all the 'big' wire AL? When I started service
>> here I was required to buy AL wire to connect the meter to the breaker
>> box on the pole and to connect that box to the breaker box in the
>> trailer.
>>
>> Also can you even buy 'small' AL wire, e.g. 10 ga? If so is it that much
>> cheaper than Cu?
>>
>> Would anyone here use AL wire for anything?
>
> Cost -- compare the price for large diameter Cu vis a vis Al and you'll
> see they "why"...
IIRC, you can use a smaller Cu wire.
> It would be unusual to require Al, most will accept either as most
> terminations these days are Cu/Al compatible. If the service gear was
> rated for Al only, then it would make sense.
I just know what the permit people told me. I guess you can't buy a Cu
rated meter box.
> I would expect a very high fraction or more of those "here" have Al in
> their own residences in at least those applications.
I missed a word. It should read: Would anyone here use AL wire for anything
else? That is would anyone here use AL wire from the breaker box to the
outlets.
On Sat, 11 Aug 2007 20:42:10 +0000, Wes Stewart <*n7ws*@ yahoo.com>
wrote:
>On Sat, 11 Aug 2007 12:41:38 GMT, Jim Behning
><[email protected]> wrote:
>
>|Speaking of useless answers. I went to some trade show years ago. I
>|got a tote bag that might have said Copper is Proper. I cannot find
>|the tote bag to see if that was the logo. Two points were made in the
>|handout and it was geared towards commercial electricians. Well maybe
>|one point. Copper flows electricity better than aluminum. 12 guage can
>|be less expensive over the life of a building versus 14 guage due to
>|lower power losses with the bigger wire. Equipment can run better with
>|lower voltage drops.
>|http://www.engineeringtoolbox.com/wire-gauges-d_419.html
>|http://www.jlmwholesale.com/images/WIREGAUGE.pdf
>|
>|Another anecdote which might be worthless. I have a friend who is
>|certified in a lot of welding techniques. He has worked in power
>|plants, oil rigs, made non destructive weld samples and seems to have
>|a good bit of experience. He occasionally uses the small portable mig
>|welder like I have in the garage. He has found that the little 120
>|volt welder does better with 10 guage service wire than it does with
>|12 guage service wire. I don't know how long the wire runs were when
>|he was doing this experimenting but it reinforces the voltage drop.
>|His eyes and skill with welds are better than my hack welds.
>
>
>First of all, it's "gauge."
>
>You don't need wire tables if you can remember that the resistance of
>a round copper conductor is given by:
>
>DC resistance ( Ohm/1000' at 20 C.) = 10 ^ (0.1 * AWG - 1)
>
>where AWG is American Wire Gauge.
>
>The resistivity of aluminum is approx 1.52 times copper.
>
>So for a 20A run using 12 AWG, 100' long (200' of wire) the copper
>loss is ~45 W.
>
>For the same run in aluminum the loss is ~69 W.
>
>The difference in efficiency (power delivered to load / power into
>wire) is 98.1% vs. 97.1%.
>
>Is this somthing to get excited about?
I am notorious for flipping letters around. Isn't dyslexia just a
wonderful thing?
Anyway it was not my argument.
http://www.copper.org/applications/electrical/energy/onesizeup.html
>> Third, if you need to 'upsize' later its a lot easier to just put in a
>> larger breaker than putting in new or more wire.
>
> If you wire for higher ampacity, then may as well install appropriately
> sized breakers and outlets, etc., at the time. Otherwise, unless wasted
> the extra money for the higher-rated outlets until that unforeseen maybe
> never to happen time in the future, placing simply a larger breaker may be
> fine for the wiring itself but not for the outlets, etc., ...
True but I was thinking of being able to add more outlets to the same line.
Example when I bought my last house there was one outlet along the wall were
I wanted to put my entertainment center I had to use 2 power strips. No big
deal there because nothing was drawing much power and very few of the items
were on at any one time. But what if in the future things need more power?
I'm guessing they will. Its a lot easier to put an outlet or two on an
existing circuit than it is to run an entire new line from the breaker box.
Who know what we will need in 10 years. Its a bit more than 10 years old
but the house mom lives in had a total of 6 fuses when it was built!! I
think when we remodeled it we added 6 more circuits, with fuses so you can
tell that's been a while ago. :)
I might change my mind when I start building. But right now its going to be
an over wired, concrete dome with metal studs and fiberglass backed
wallboard. I'm a bit paranoid about fire so there will be very few
flammable building materials used in it.
>>Personally, when it comes to wiring bigger IS better. Even more so when
>>it
>>comes to a workshop. I'm looking at building a new home in a few years
>>and
>>if I can afford it I will 'over wire' the entire house for a couple of
>>reasons.
>
> Yeah, right. My uncle did that when he built his house back in the
> '60s. He ran 12 ga to every single device in the house--receptacles,
> switches, lights. At the tiime I thought it was a good idea--after
> all, it's only one size up, right?
>
> Said he'd never do it again. He nearly crippled himself wiring all
> those living room receptacles designed to accommodate a reading lamp
> and the bedroom receptacles designed for an alarm clock. To what
> purpose? Don't believe me? Go stuff a half dozen boxes with 12 gauge
> wire and wire the receptacles. Then do the same with 14 guage wire.
> The difference in effort is not trivial.
I'm not sure what you mean. Are you saying that its tough to have three 10
ga wires coming into one box or are you saying its hard to work 10 ga wire?
Other than 3 way lights why would you have that many wires and a swith or
outlet in one box? I've put in a several 220VAC outlets into regular boxs
(the kind you use to power portable 220 heaters) using 10ga copper. Stiff
but not that bad.
> The shop, on the other hand, is a supportable venture in the larger
> wire department. However, unless you're looking at something
> significantly greater than say 1000 ft^2 and without a nearby or en
> suite load center, you gain virtually nothing by going up a wire size.
>
> If you're running 3HP machines (kind of a regular, home shop size
> motor) you don't need any more than a 20A circuit at 240V. If you're
> running 5HP you have to go to 30A anyway (and it's more than enough)
> so why would you need to go to 40A?
The shop I'm WANTING to build will be large enough to get a tractor trailer
rig into with the doors shut. It'll have a woodworking area, a metal
working area, storage for my little farm tractor and its stuff as well as an
area for working on vehicles. The last time I drew it using a computer
building program it was something 60' X 80'.
Of course the shop I'm probably going to wind up with will be somewhat
smaller. Big enough I can get the truck in and JUST be able to shut the
doors and that after I move my tractor, bush hog and the like out.
>>Second, its much more difficult to have an electrical fire if you wire a
>>20
>>amp breaker with wire that will carry 40 amps or so.
>
> You can't be serious. It's not nearly as difficult as finding a 15 or
> 20 amp receptacle into which you can stuff that 8 gauge wire.
Only slightly. Try 15 amp breaker with 20 amp wire. Of course the weakness
I have found in the entire system is the outlet itself. Wires work loose or
bad contacts cause arcing which cause fires.
>>Third, if you need to 'upsize' later its a lot easier to just put in a
>>larger breaker than putting in new or more wire.
>
> Dumb idea #3. The difference in cost between a 20A breaker and 30A
> breaker is negligible (they're virtually the same in the Square D QO
> line). If you really were commited to running 10 gauge wire throughout
> the house (ignoring, for the moment, the difficulty in working it and
> the utter lack of need for it) why would you not go ahead and put 30A
> breakers in?
The house is still at least 3 years from being started so I might if there
isn't that much difference in price and the code Nazis allow it I probably
will. After dealing with them just trying to put in a trailer I hate to
think about the rules they have for wiring a new house.
I'm also going to do other 'dumb' things. Here's just a few. I'll run at
least one 220VAC to each room and put in an outlet. My old house had a
couple and I found that a portable 220VAC heater (which I still have a few)
can make a room nice and warm quickly w/o needing to crank the heat in the
entire house. I'll run 1" water lines from the pump to the house. The
heating and cooling will be suplmented, hopefully totally ran, by a home
built solar thermal system (yes I'll be making cold air using heat from the
sun). I'll use metal studs and beams. The wallboard will have fiberglass,
not paper, backing.
> All this talk about sizing up electrical circuits is roughly the same
> as knot tying by someone who doesn't know how to tie knots--if one
> loop is good, two or three must be two or three times better, right?
> Hah.
That's me. If at all possible I put a double half hitch behind a bowline,
use 500# rated line to lift 200# and put one more tie down if there's room.
I also don't work under anything that is only supported by hydraulic
cylinders. Don't work around flamable items w/o a fire extinguisher near
by. BTW, I have a fire X in the kitchen, one in each car/truck and one on
my tractor. Don't drive w/o my seatbelt nor ride a motorcycle w/o a helmet.
All of this and then some. None of those take much more time nor money and
can save money and even a life if something goes wrong.
But I don't want to make you do any of that if you don't want to.
You have always heard there are no stupid questions. Maybe the
questions were asked for reference. To see what others had done when
there shop was wired. I think it was a legitimate question asking the
difference between the wires. If he is to have someone wire the shop
are all electricians going to wire with 12/2 on 220 and 10/2 on 110?
Knowledge is a good thing and being able to tell the electrician what
you want can only make the shop that much better.
John
On Sat, 11 Aug 2007 14:09:53 -0700, Robatoy <[email protected]>
wrote:
>On Aug 11, 12:51 am, LRod <[email protected]> wrote:
>> On Fri, 10 Aug 2007 14:19:22 -0700, [email protected] wrote:
>>
>> [electrical question snipped]
>>
>> You have just been introduced to the hazard of soliciting specialized
>> advice on the internet.
>
>I'll take that one step further. If a guy has to ask the difference
>between 10/2, 10/3. 12/2 etc... WTF is he doing wiring his shop?
>
>For chrissakes, call somebody who knows and who has the certification
>and insurance!!
>
>And GET A FARKING PERMIT!!
>
>(Yes, yes, I know, I know... there are many here who have the
>knowledge and confidence to do that kind of work themselves, but when
>questions indicate a complete and total ignorance of the topic at
>hand.........)
>
>r
On Fri, 10 Aug 2007 16:47:05 -0600, Chris Friesen
<[email protected]> wrote:
>Lew Hodgett wrote:
>
>> BTW, Lew's rule for shop wiring:
>>
>> #12 AWG for all 1Pole(120V) circuits and #10AWG for all 2Pole(240V)
>> circuits.
>
>I agree that it makes sense to wire a shop with 20A circuits for
>receptacles. Just gives a bit of leeway if you plug in a couple things
>onto one circuit.
>
>However, I think that wiring all the 240V circuits with #10 is overkill
>given that it costs significantly more than #12. How many people have
>5HP tools in their home shop? I have one 30A outlet for an electric
>heater and a future welder. All the rest of my 240V outlets are 20A.
>
>I do think it's a good idea for critical large items (compressor and
>dust collector) get their own circuits. Most of the others (tablesaw,
>planer, jointer, bandsaw) could realistically share a circuit or two in
>a home shop since usually only one will be in use at any given time.
>
>Chris
I know in home shops it is usually a non issue but factor in distance
from the panel when determining wire size. In my opinion I would never
put in less than 12g on 120 and 10g on 240v service. The cost is
minimal and downsizing breakers if critical is ok but never step over
your wire size.
When computing amp load just consider how many or what machines will
be running at the same time on the same circuit.
Never wire a machine without a ground. 240 volt motors only require
two hot legs but always ground as well. 120 volt service requires a
hot leg and a neutral PLUS the ground. Neutral and ground should never
be the same!
With 3 phase service any 240 motor will run fine with one high leg and
one low or two low legs but still ground the machine.
and there you have my $.02 worth.
On Fri, 10 Aug 2007 14:19:22 -0700, [email protected] wrote:
[electrical question snipped]
You have just been introduced to the hazard of soliciting specialized
advice on the internet. In the gaggle of answers so far, you have
gotten some good information, some incorrectly applied information,
some information given with good intentions but poorly stated, and
some plain incorrect information. You've even had a couple of
responses telling other responders that they are incorrect.
The big problem is, how do you know which is which? Unless you know
the players, you can't. My drivel can look just as authoritative as
anyone else's to someone relatively new to the Wreck. The fact is,
there are about three or four posters here whose electrical
information you can trust. Probably at the top of the list is Doug
Miller. View anyone else's answers with suspicion. I'm surprised he
hasn't posted already. I'm sure he will, however. He can cite the NEC
chapter and verse. Hardly anyone else here can.
By the way, just to throw a monkey wrench in the works for all the
oh-so-sure posters about the number of conductors in a cable--it
wasn't so long ago ( in my lifetime and I can personally attest to
it), that if you wanted a ground wire with your Romex (trade name for
NMC or non metallic cable) you had to say "with ground." It was not
implied. Granted that's no longer the case, but it does illustrate how
gray an answer can sometimes be. Could be important is some old work.
My advice (and you can take this one to the bank) is don't be
satisfied that you have all the information you need based on the
answers you've received so far.
--
LRod
Master Woodbutcher and seasoned termite
Shamelessly whoring my website since 1999
http://www.woodbutcher.net
Proud participant of rec.woodworking since February, 1997
email addy de-spam-ified due to 1,000 spams per month.
If you can't figure out how to use it, I probably wouldn't
care to correspond with you anyway.
On Mon, 13 Aug 2007 15:35:36 GMT, "no spam" <[email protected]> wrote:
|> Speaking of useless answers. I went to some trade show years ago. I
|> got a tote bag that might have said Copper is Proper. I cannot find
|> the tote bag to see if that was the logo. Two points were made in the
|> handout and it was geared towards commercial electricians. Well maybe
|> one point. Copper flows electricity better than aluminum. 12 guage can
|> be less expensive over the life of a building versus 14 guage due to
|> lower power losses with the bigger wire. Equipment can run better with
|> lower voltage drops.
|
|I know copper wire has many advantages over AL wire but I have a question or
|two.
|
|First off why is almost all the 'big' wire AL? When I started service here
|I was required to buy AL wire to connect the meter to the breaker box on the
|pole and to connect that box to the breaker box in the trailer.
|
|Also can you even buy 'small' AL wire, e.g. 10 ga? If so is it that much
|cheaper than Cu?
|
|Would anyone here use AL wire for anything?
Cost and weight.
As I stated earlier, the resistivity of Al v. Cu is about 1.5 to 1.7
depending on the alloy. Expressed another way, increasing the Al wire
by approximately two gauge equalizes the losses. (Cu 12 AWG ~ Al 10
AWG)
For residential wiring, the downsides of Al are corrosion, creep and
dissimilar metals issues when connected to copper. The lower wire
cost is eaten up by the specialized connections required to use it.
For overhead long distance transmission lines the cost and weight
advantages of Al are a big deal.
On 12 Aug 2007 08:23:31 GMT, Puckdropper <[email protected]>
wrote:
>
> Sometimes I know that I don't know.
>;-)
>
>Puckdropper
Then I would say you've advanced to the 2nd level of knowledge on that
particular topic.
1. Don't know that you don't know.
2. Know that you don't know.
3. Know that you know.
4. Don't know that you know.
Tom Veatch
Wichita, KS
USA
On Mon, 13 Aug 2007 15:35:37 GMT, "no spam" <[email protected]> wrote:
>Personally, when it comes to wiring bigger IS better. Even more so when it
>comes to a workshop. I'm looking at building a new home in a few years and
>if I can afford it I will 'over wire' the entire house for a couple of
>reasons.
Yeah, right. My uncle did that when he built his house back in the
'60s. He ran 12 ga to every single device in the house--receptacles,
switches, lights. At the tiime I thought it was a good idea--after
all, it's only one size up, right?
Said he'd never do it again. He nearly crippled himself wiring all
those living room receptacles designed to accommodate a reading lamp
and the bedroom receptacles designed for an alarm clock. To what
purpose? Don't believe me? Go stuff a half dozen boxes with 12 gauge
wire and wire the receptacles. Then do the same with 14 guage wire.
The difference in effort is not trivial.
The shop, on the other hand, is a supportable venture in the larger
wire department. However, unless you're looking at something
significantly greater than say 1000 ft^2 and without a nearby or en
suite load center, you gain virtually nothing by going up a wire size.
If you're running 3HP machines (kind of a regular, home shop size
motor) you don't need any more than a 20A circuit at 240V. If you're
running 5HP you have to go to 30A anyway (and it's more than enough)
so why would you need to go to 40A?
>Second, its much more difficult to have an electrical fire if you wire a 20
>amp breaker with wire that will carry 40 amps or so.
You can't be serious. It's not nearly as difficult as finding a 15 or
20 amp receptacle into which you can stuff that 8 gauge wire.
You'd be hard pressed working 10 gauge (30A) wire around very many
boxes before you realized what a load of an idea that was. Forget 8
gauge.
>Third, if you need to 'upsize' later its a lot easier to just put in a
>larger breaker than putting in new or more wire.
Dumb idea #3. The difference in cost between a 20A breaker and 30A
breaker is negligible (they're virtually the same in the Square D QO
line). If you really were commited to running 10 gauge wire throughout
the house (ignoring, for the moment, the difficulty in working it and
the utter lack of need for it) why would you not go ahead and put 30A
breakers in?
All this talk about sizing up electrical circuits is roughly the same
as knot tying by someone who doesn't know how to tie knots--if one
loop is good, two or three must be two or three times better, right?
Hah.
--
LRod
Master Woodbutcher and seasoned termite
Shamelessly whoring my website since 1999
http://www.woodbutcher.net
Proud participant of rec.woodworking since February, 1997
email addy de-spam-ified due to 1,000 spams per month.
If you can't figure out how to use it, I probably wouldn't
care to correspond with you anyway.
On Sat, 18 Aug 2007 13:36:19 GMT, [email protected] (Doug Miller)
wrote:
>In article <[email protected]>, Mike M <[email protected]> wrote:
>
>>#12 thhn cu wire is actually rated for about 35 amps.
>
>30A, actually.
>
Shows how bad my memory is getting.
>>The
>>restriction to 20 amps is mainly based on the rating of the terminal
>>on the CB.
>
>That's part of it, but not the only reason. 10, 12, and 14 gauge wires are the
>sizes most commonly used in residential circuits. The allowable overcurrent
>protection is set by the Code at a value significantly under the actual
>ampacity of the wires to reduce the risk of fire from overloading a circuit.
>
>>You may use the higher ampacity ratings before taking your
>>derating but still can't have over a 20 amp breaker.
>
>Which means that the higher ampacity ratings are, for all practical purposes,
>irrelevant. :-)
This is true for residential work generally, but in commercial work
where you might be derating for continuous load, number of conductors
in pipe, as well as ambient temperature it can make a difference.
Mike M
On Tue, 14 Aug 2007 15:48:08 +0000, LRod <[email protected]>
wrote:
[snip]
|
|Actually, I'd be surprised if 10/2 was used in 120V circuits at all.
Very common in the recreational vehicle world. Let me rephrase...120V,
30A circuits are very common in the RV world. (What wire size they use
is unknown) Most RV parks provide 30A hookups; with some supplying
50A circuits for "big rigs", those with dual A/C, washer/driers, etc.
On Mon, 13 Aug 2007 00:36:47 -0400, Bradford Chaucer
<[email protected]> wrote:
>10/2 has a white and black and is used in 120volt circuits only.
Are you saying that I was in error using 10/2 for my 240V water
heater?
I don't think so. There is no requirement to use xx/3 wire for 240V if
a neutral isn't called for (as it is with ranges and dryers since the
'90s). Your table saw or planer circuit could just as correctly be run
with xx/2 cable.
The NEC makes a provision for using the white conductor in NMC (Romex)
as a hot lead for just that circumstance (and also for switching)::
you must mark the white wire at each end as a "hot" conductor. A piece
of tape will do, although I used a red magic marker coloring each
white conductor in all my 240V shop circuits--I could just as easily
have colored them black, as there's no "polarity" marking requirement,
either.
--
LRod
Master Woodbutcher and seasoned termite
Shamelessly whoring my website since 1999
http://www.woodbutcher.net
Proud participant of rec.woodworking since February, 1997
email addy de-spam-ified due to 1,000 spams per month.
If you can't figure out how to use it, I probably wouldn't
care to correspond with you anyway.
In article <[email protected]>,
"Mike Marlow" <[email protected]> wrote:
> This is just patently incorrect. Perhaps it's a typo, but in matters like
> this good proof reading becomes essential. 10/2 is not used in 120v
> circuits only.
Right. It makes dandy speaker wire.
On Fri, 10 Aug 2007 21:27:42 -0400, Robert Haar <[email protected]>
wrote:
>On 8/10/07 6:47 PM, "Chris Friesen" <[email protected]> wrote:
>
>> Lew Hodgett wrote:
>>
>> I agree that it makes sense to wire a shop with 20A circuits for
>> receptacles. Just gives a bit of leeway if you plug in a couple things
>> onto one circuit.
>
>Start off by looking at the power requirements of the tools that you are
>likely to use. With the exception of a dust collector, you probably won't
>run any of your tools at the same time.
>
>20A circuits for standard 110v outlets is about right for a shop with
>typical hand held power tools.
>
>>
>> However, I think that wiring all the 240V circuits with #10 is overkill
>> given that it costs significantly more than #12. How many people have
>> 5HP tools in their home shop? I have one 30A outlet for an electric
>> heater and a future welder. All the rest of my 240V outlets are 20A.
>>
>> I do think it's a good idea for critical large items (compressor and
>> dust collector) get their own circuits. Most of the others (tablesaw,
>> planer, jointer, bandsaw) could realistically share a circuit or two in
>> a home shop since usually only one will be in use at any given time.
>
>Some other suggestions:
>
>Put your lights on a separate circuit. It's a pain when you pop a breaker
>and the lights go out.
>
>If you have large stationery tools, put in a dedicated circuit for each one.
>
>Put in lots of outlet. One for every three to four feet of wall at a
>minimum.
>
>Think about where you might put benches, etc. It helps to have plenty of
>outlets nearby, including some above the bench. I put all the outlets in my
>shop four feet above the floor.
Excellent advice save the bending and box/plug are cheap. I have a
rule of thumb of 5 boxes per circuit. You can never have enough. We
have more than one stationary tool on the same circuit because they
never run at the same time.
On Sun, 12 Aug 2007 12:16:36 -0500, "Morris Dovey" <[email protected]>
wrote:
>This sounds remarkably like a former Secretary of Defense's
>semi-coherent ramblings on Middle East intelligence...
No, it's more like the redneck statement of the three laws of
thermodynamics;
1. You can't win.
2. You can't break even.
3. You can't get out of the game.
Tom Veatch
Wichita, KS
USA
On Mon, 13 Aug 2007 17:19:43 GMT, [email protected] (Doug Miller)
wrote:
>In article <[email protected]>, "no spam" <[email protected]> wrote:
>
>>Personally, when it comes to wiring bigger IS better.
>
>Nonsense. Except on very long runs, bigger wire provides no advantages at all,
>and does provide significant disadvantages:
>a) higher cost
>b) greater difficulty in installation
>c) difficulty in finding compatible receptacles (for example, try finding a
>15A rated receptacle that will accept AWG8 wire)
>d) the larger the wire, the fewer of them the Code allows you to put in a box.
>
>>Even more so when it
>>comes to a workshop. I'm looking at building a new home in a few years and
>>if I can afford it I will 'over wire' the entire house for a couple of
>>reasons. First, look around your house now and think about how it looked 10
>>years ago. How many more electrical items do you have now? How many more
>>might we have in 10 more years?
>
>This purpose is achieved much more easily, and at considerably lower cost, by
>keeping the wire size the same and increasing the number of circuits.
>>
>>Second, its much more difficult to have an electrical fire if you wire a 20
>>amp breaker with wire that will carry 40 amps or so.
>
>Nonsense again. The risk of electrical fire is not significantly greater using
>AWG12 wire on a 20A breaker, compared to using AWG8 -- and in fact, you'd
>probably be creating a substantial risk of fire by attempting to connect a
>standard receptacle to conductors that are too large to fit under the screw
>terminals. Sure, you can pigtail the connections -- let me know when you're
>getting ready to wire up those receptacles. I want to come watch you stuff
>the wires back in the box; I could use a few laughs.
>
>And then I'll phone the local electrical inspector. "Wire that will carry 40
>amps or so" is AWG8 or larger. You might want to consult Table 314.16(A) in
>the NEC to see how many AWG8 conductors the Code allows you to put in a
>standard device box. (Hint: except with the largest device box available, it's
>not enough to supply a receptacle -- and forget about feeding through to
>another receptacle, or using anything larger than AWG8.)
>
>>Third, if you need to 'upsize' later its a lot easier to just put in a
>>larger breaker than putting in new or more wire.
>
>Nonsense yet again. What, exactly, do you plan to "upsize" to, anyway? It's a
>Code violation to put a 20A receptacle on a circuit protected by anything but
>a 20A breaker. The larger wire serves no purpose at all.
#12 thhn cu wire is actually rated for about 35 amps. The
restriction to 20 amps is mainly based on the rating of the terminal
on the CB. You may use the higher ampacity ratings before taking your
derating but still can't have over a 20 amp breaker.
Mike M
On Fri, 10 Aug 2007 14:19:22 -0700, [email protected] wrote:
>In recent posts I have heard mention of 12/2 and 10/2 wire, as well as
>12/3 and 10/3 wire. What is the difference and what would you wire a
>new shop with?
>
>I assume the 12/2 and 10/2 mean with ground.? What is the extra wire
>in the 12/3 and 10/3 for? Is that for wiring 220V?
So, with 60+ (sometimes contentious) posts and not a peep from the OP,
does anyone else get that sharp pain in the cheek feeling that comes
from striking the lure?
--
LRod
Master Woodbutcher and seasoned termite
Shamelessly whoring my website since 1999
http://www.woodbutcher.net
Proud participant of rec.woodworking since February, 1997
email addy de-spam-ified due to 1,000 spams per month.
If you can't figure out how to use it, I probably wouldn't
care to correspond with you anyway.
Mentioned are 15 and 20 amp 110 circuits.
Is there any reason to have 15 amp circuits?
Wire everything with 20 amp outlets and be done with it.
Jim
On Fri, 10 Aug 2007 21:27:42 -0400, Robert Haar <[email protected]>
wrote:
>On 8/10/07 6:47 PM, "Chris Friesen" <[email protected]> wrote:
>
>> Lew Hodgett wrote:
>>
>> I agree that it makes sense to wire a shop with 20A circuits for
>> receptacles. Just gives a bit of leeway if you plug in a couple things
>> onto one circuit.
>
>Start off by looking at the power requirements of the tools that you are
>likely to use. With the exception of a dust collector, you probably won't
>run any of your tools at the same time.
>
>20A circuits for standard 110v outlets is about right for a shop with
>typical hand held power tools.
>
>>
>> However, I think that wiring all the 240V circuits with #10 is overkill
>> given that it costs significantly more than #12. How many people have
>> 5HP tools in their home shop? I have one 30A outlet for an electric
>> heater and a future welder. All the rest of my 240V outlets are 20A.
>>
>> I do think it's a good idea for critical large items (compressor and
>> dust collector) get their own circuits. Most of the others (tablesaw,
>> planer, jointer, bandsaw) could realistically share a circuit or two in
>> a home shop since usually only one will be in use at any given time.
>
>Some other suggestions:
>
>Put your lights on a separate circuit. It's a pain when you pop a breaker
>and the lights go out.
>
>If you have large stationery tools, put in a dedicated circuit for each one.
>
>Put in lots of outlet. One for every three to four feet of wall at a
>minimum.
>
>Think about where you might put benches, etc. It helps to have plenty of
>outlets nearby, including some above the bench. I put all the outlets in my
>shop four feet above the floor.
<[email protected]> wrote in message
news:[email protected]...
> In recent posts I have heard mention of 12/2 and 10/2 wire, as well as
> 12/3 and 10/3 wire. What is the difference and what would you wire a
> new shop with?
>
> I assume the 12/2 and 10/2 mean with ground.? What is the extra wire
> in the 12/3 and 10/3 for? Is that for wiring 220V?
>
> Jim
10/3 and 12/3 are with ground. Also there are only 3 wires in those cables.
10/2 and 12/2 only have 2 wires.