Hi, All,
Very soon, I will be ordering a table saw, jointer, and maybe a
planer. Santa was VERY GOOD!!! All will run on 220. My shop has 220
at the box, at least 2 circuits. The previous owner ran a welder and
huge compressor, so the amps are there.
I did some wiring 25 years ago, but am a little rusty. I think I
want junction boxes every 6-8 feet or so around the shop, so I can plug
in things or move them to a different location. Is there a standard
plug, like a dryer or oven plug that I should use? Does it matter for
my shop? I understand I will want to keep the plug to equipment
distance as short as possible, but would like the ability to plug the
saw in on one wall, then maybe later on the other wall for a different
job, or for whatever reason.
Should I run separate conduit for the 220? I have 110 boxes every
six feet at chest hight currently, and it might be possible to snake
additional wire down the same conduit, and add a 2nd junction box for
the 220???
Thank you all for your help and suggestions.
Regards,
Rich.....
DJ Delorie <[email protected]> writes:
>
>"Mike Marlow" <[email protected]> writes:
>> > My inspector's attitude is 100% health and safety - if it's safe,
>> > he'll pass it, if it's not, he won't. It made it easy to guess what
>> > would pass.
>>
>> I'll bet his attitude is more like, "if it's up to code, he'll pass it".
>
>Well, he told me what his attitude was when we first met, and his
>actions backed it up. But, if you know something about my inspector
>that I don't, please, let us all know about it.
>
>For example, we were using a type of insulation he was unfamiliar with
>it. Code said it was OK, but he also took a bit of it home to see how
>it reacted to fire, just in case.
And how, exactly, was he qualified to make any analysis of "how it
reacted to fire"? Which testing criteria did he use? How was his
test lab equiped? Or did he simply try to set it afire?
scott
Amperage generally isn't a problem when running shop tools at 220V.
The current is half what it would be at 110V, so 20 amps is usually
more than sufficient.
Likewise, having a long power cord on your tools is usually less of an
issue at 220V. Power (in watts) dissipated in the cord = I^2*R, where
I is current (in amps) and R is the resistance of the cord (in ohms).
Since current is half at 220V, the power dissipated in the cord is 1/4
what it would be at 110V. Thus, you can have a cord four times as long
as you could at 110V. And even then the cord wouldn't get as hot
because the power would be dissipated over a greater length.
I'd put a pair of standard 20 amp 220V outlets every 10 or 15 feet, fed
with 12/3 (plus ground) wire. Since your tools won't need a neutral
connection, you could also get away with 12/2 wire, but for the small
extra cost of the 3-conductor wire, it could potentially save you or a
future owner of your house some confusion and danger, since you'd have
to use the white (normally neutral) wire as hot.
I think they're just the common 240V breakers that have an "arm" which
connects the two switches together. That way, if either 120V leg
trips, the other one is automatically tripped as well. I suppose this
would be as opposed to using two 120V breakers in adjacent slots, where
they weren't physically bound together.
Am I right?
On 2006-01-29 19:06:39 -0800, "rich" <[email protected]> said:
> Is there a standard
> plug, like a dryer or oven plug that I should use?
NEMA 6-15P for 240 volts, 15 amps.
NEMA 6-20P for 240 volts, 20 amps.
If your machines came with a molded corset, they most likely conformed
to those configurations.
Use 12 AWG wire for these, and install a NEMA 6-20R, which will accept
both the NEMA 6-15P and NEMA 6-20P.
Other configurations are available for 30, 40 and 50 amp loads.
On 2006-01-30 17:07:33 -0800, Charles Krug <[email protected]> said:
> I've never seen where it was "legal" but my Practical view is that I
> wouldn't do it even if it were allowed.
It's called a multiwire branch circuit, and it's allowed.
It's allowed primarily because in any box there is never more than 120
line-to-ground, even though there is 240 line-to-line.
The CB which protects a multiwire branch circuit must be a "common
trip" type, so should a 120 side blow, the other 120 side and the 240
blow simultaneously.
Essentially, you wire your boxes as 120/240, using 12/3+G; you tap into
120 alternating black (L) and white (N) then red (L) and white (N), and
so on, from box to box, and if you want 240 in a box then you tap into
black (L1) and red (L2). Wire G as usual.
I used 20a 220 receptacles. It's very similar to the 120v flavor, but
one of the blades is horizontal rather than vertical. I believe it
uses the same faceplate, and plugs are pretty cheap. For 20A 220V
it's fine. The 30a or greater have those giant plugs, but for
converting shop tools to 220, 20A is sufficient. Realize all 120V
tools will run at 1/2 the amps on 220. You don't need 8ga wire and
30A plugs. I used 12ga 2-conducter (plus grd) wire, and 12ga cords
(bought long extension cords and cut it to size.. cheaper than buying
wire in bulk). I think most 1-1.5hp tools are wired with about 14ga
stranded.. I could have just used that. But I went ahead and rewird
with about 15-20' of 12ga stranded. I did this on my TS and Jt. I
just used the existing wire on my DC. I'm still running my BS and DP
at 120v.
Maybe an electrician can chime in here.. but I did some homework, and
simple 220V at 20A and below is pretty simple. I would not mix 120
and 220 in the same box.. but that's just me. Code might allow it.. I
just don't know.. but it seemed simpler for me to keep them seperate.
"DJ Delorie" <[email protected]> wrote in message
news:[email protected]...
>
> "Mike Marlow" <[email protected]> writes:
>
> > Are you saying he rejects wiring that is up to code because it does
> > not meet his definition of safety?
>
> Well, I've heard stories about inspectors that require more than what
> code requires. For example, carpeting. Carpeting is not a health or
> safety issue (assuming the underlayment is safe) but I've heard of
> inspectors that require it for occupancy, and would fail bare floor.
Well - I've heard that John F. Kennedy was assinated by the mafia too.
Sometimes you have to think about the logic of what you hear.
>
> > Or perhaps even that he accepts things that are not up to code
> > because in his opinion they are somehow safe?
>
> No, obviously he requires the house also meet code. There's more to
> an inspection than code, though. And there's more to an inspection
> than the electrical bits too.
Indeed there is more to a house inspection than electrical, but the
conversation was about wiring. There is nothing more to it than code -
whether that is NEC by default, or local augmentations. But - electrical
inspection is not about some local inspector deciding to inspect based on
what *he* considers safe.
>
> > And... I'll bet he passed it right? What did his "test" prove?
>
> It proves that he doesn't blindly follow the code, and that he's
> willing to learn, and that in the end it's HIS responsibility to make
> sure the house is safe, not some book's.
Wrong. And I'll bet his little home cooked test provided no meaningful
data. That "book" happens to be one of the most respected collections of
wisdom known to the electrical world. Any inspector who believes he's
somehow above that should get your worry sense in high gear. In the end, he
didn't accomplish anything to ensure your house or your wire was any safer.
He put on a good show, but where are the results of his tests?
>
> > You're wired to code and you can't do any better than that,
>
> Sure you can. Code says 15 amps, I can wire to 20. I have more
> outlets than "every N feet". I have GFIs where they're not strictly
> required.
Yeah - a lot of us do that, but I think you know what I was referring to
with my comment. I used a colloquialism.
--
-Mike-
[email protected]
"DJ Delorie" <[email protected]> wrote in message
news:[email protected]...
>
> "Mike Marlow" <[email protected]> writes:
> > > My inspector's attitude is 100% health and safety - if it's safe,
> > > he'll pass it, if it's not, he won't. It made it easy to guess what
> > > would pass.
> >
> > I'll bet his attitude is more like, "if it's up to code, he'll pass it".
>
> Well, he told me what his attitude was when we first met, and his
> actions backed it up. But, if you know something about my inspector
> that I don't, please, let us all know about it.
I'd bet a small sum of money, with no knowledge of your inspector that what
he really means is that if it meets code it's fine. Are you saying he
rejects wiring that is up to code because it does not meet his definition of
safety? Or perhaps even that he accepts things that are not up to code
because in his opinion they are somehow safe? I would like to believe he
does not view himself as above NEC and decides for himself what is safe. I
believe he probably relies on NEC.
>
> For example, we were using a type of insulation he was unfamiliar with
> it. Code said it was OK, but he also took a bit of it home to see how
> it reacted to fire, just in case.
And... I'll bet he passed it right? What did his "test" prove? Not to be
insulting, but this kind of inspector sounds like he is just entertaining
himself with his tests. He surely does not really believe that he is going
to somehow dismiss the findings of UL or any other industry certification
with his home grown tests, does he? My bet - no, he's going to defer to
NEC.
>
> Since our town and state use the national code, I could probably argue
> with him about anything that wasn't strictly code, but I'm not that
> stupid. He was acting in my best interests, and it was obviously so,
> and I was happy about it.
If you're happy, then that's all that matters. You're wired to code and you
can't do any better than that, and you like what your inspector says. Don't
see how that suggests that he doesn't defer to NEC though.
--
-Mike-
[email protected]
peterh5322 <[email protected]> wrote:
>On 2006-01-30 17:07:33 -0800, Charles Krug <[email protected]> said:
>
>> I've never seen where it was "legal" but my Practical view is that I
>> wouldn't do it even if it were allowed.
>
>It's called a multiwire branch circuit, and it's allowed.
>
>It's allowed primarily because in any box there is never more than 120
>line-to-ground, even though there is 240 line-to-line.
>
>The CB which protects a multiwire branch circuit must be a "common
>trip" type, so should a 120 side blow, the other 120 side and the 240
>blow simultaneously.
>
>Essentially, you wire your boxes as 120/240, using 12/3+G; you tap into
>120 alternating black (L) and white (N) then red (L) and white (N), and
>so on, from box to box, and if you want 240 in a box then you tap into
>black (L1) and red (L2). Wire G as usual.
>
That's the way I have my shop wired. In fact, I found fixtures that
have one 240 and one 120 outlet. I put one of these and one dual 120
outlet in each box, with the 120 outlet in the 240 fixture on one side
of the circuit, and the 120 fixture on the other side.
But I haven't seen the "common trip" discussion, just assuming that
was how it worked. How can I tell if that is what I have?
--
Alex -- Replace "nospam" with "mail" to reply by email. Checked infrequently.
On 2006-01-30, [email protected]
<[email protected]> wrote:
>
> Maybe an electrician can chime in here.. but I did some homework, and
> simple 220V at 20A and below is pretty simple. I would not mix 120
> and 220 in the same box.. but that's just me. Code might allow it.. I
> just don't know.. but it seemed simpler for me to keep them seperate.
I've never seen where it was "legal" but my Practical view is that I
wouldn't do it even if it were allowed.
Even up to 60A (ovens) or higher is pretty straightforward. You decide
what ampacity you need by the nameplate of the device (required to be
accurate), choose your wire gauge based on your tolerence for voltage
drop, choose your conduit fill by looking it up in a table OR
calculation.
Nothing about it is especially Difficult, but it Does require attention
to detail.
Always work to your comfort level and call an electrician if any part of
the job makes you UNcomfortable, preferably before starting it.
My comfort level is, "If I can kill power and the source panel has
capacity. (space and ampacity) for the given job." YMMV and work within
your comfort level.
Charles Krug <[email protected]> writes:
>On 2006-01-30, [email protected]
><[email protected]> wrote:
>>
>> Maybe an electrician can chime in here.. but I did some homework, and
>> simple 220V at 20A and below is pretty simple. I would not mix 120
>> and 220 in the same box.. but that's just me. Code might allow it.. I
>> just don't know.. but it seemed simpler for me to keep them seperate.
>
>I've never seen where it was "legal" but my Practical view is that I
>wouldn't do it even if it were allowed.
It's not a problem to mix 220v and 120v current carrying conductors
in a raceway (read: conduit), as the potential to ground for any single
conductor is 120v.
It is an NEC violation to mix 600v(for example) and 120/220 in the same raceway, for obvious
reasons.
scott
"DJ Delorie" <[email protected]> wrote in message
news:[email protected]...
>
> [email protected] (Scott Lurndal) writes:
> > It's not a problem to mix 220v and 120v current carrying conductors
> > in a raceway (read: conduit), as the potential to ground for any
> > single conductor is 120v.
>
> It might be that all the conductors in a given box have to be on the
> same breaker, though. Ask your local inspector to make sure.
It might not be.
--
-Mike-
[email protected]
"DJ Delorie" <[email protected]> wrote in message
news:[email protected]...
>
>
> My inspector's attitude is 100% health and safety - if it's safe,
> he'll pass it, if it's not, he won't. It made it easy to guess what
> would pass.
I'll bet his attitude is more like, "if it's up to code, he'll pass it".
--
-Mike-
[email protected]
"rich" <[email protected]> wrote in message
news:[email protected]...
> Hi, All,
>
> Very soon, I will be ordering a table saw, jointer, and maybe a
> planer. Santa was VERY GOOD!!! All will run on 220. My shop has 220
> at the box, at least 2 circuits. The previous owner ran a welder and
> huge compressor, so the amps are there.
>
> I did some wiring 25 years ago, but am a little rusty. I think I
> want junction boxes every 6-8 feet or so around the shop, so I can plug
> in things or move them to a different location. Is there a standard
> plug, like a dryer or oven plug that I should use? Does it matter for
> my shop? I understand I will want to keep the plug to equipment
> distance as short as possible, but would like the ability to plug the
> saw in on one wall, then maybe later on the other wall for a different
> job, or for whatever reason.
>
> Should I run separate conduit for the 220? I have 110 boxes every
> six feet at chest hight currently, and it might be possible to snake
> additional wire down the same conduit, and add a 2nd junction box for
> the 220???
>
If you have the required space in the conduit mixing the two is OK. For the
receptacles I think I would match the plug on the largest (most amperage)
piece of 220 equipment that you have.
On 31 Jan 2006 20:58:39 -0800, "Josh" <[email protected]> wrote:
>I think they're just the common 240V breakers that have an "arm" which
>connects the two switches together. That way, if either 120V leg
>trips, the other one is automatically tripped as well. I suppose this
>would be as opposed to using two 120V breakers in adjacent slots, where
>they weren't physically bound together.
>
>Am I right?
2 single pole breakers with a handle tie will not reliably trip the
other side when one side trips.
The 2005 code has addressed that and where common trip is required,
handle ties will not suffice.
A real 2 pole breaker does have internal trip capability that trips
both when one goes.
"dnoyeB" <[email protected]> wrote in message
news:[email protected]...
>
> Only difficult part is getting shocked. Outside of that, screwing down
> bolts and running wire through tube is not too tough.
>
Getting shocked - difficult??? Heck - ain't nothing difficult about
getting shocked.
--
-Mike-
[email protected]
On 29 Jan 2006 19:06:39 -0800, "rich" <[email protected]> wrote:
> Should I run separate conduit for the 220? I have 110 boxes every
>six feet at chest hight currently, and it might be possible to snake
>additional wire down the same conduit, and add a 2nd junction box for
>the 220???
1/2" conduit unlikely, but possible with some grease (wire pulling
grease) two hot wires 12 gauge and one 10 gauge for neutral 30 amp 220
volt, three 10 gauge will not fit. plus the two at least 14 gauge wire
for a 15 amp 120 volt, 12 gauge for 20 amp. Fitting wires to tightly
in the conduit can cause problems beyond just pulling them. I would
pull the current wires out and pull the whole new set both 120 and 220
it is just easier. Reuse the original wire.
Mark
(sixoneeight) = 618
Charles Krug wrote:
> On 2006-01-30, [email protected]
> <[email protected]> wrote:
>
>>Maybe an electrician can chime in here.. but I did some homework, and
>>simple 220V at 20A and below is pretty simple. I would not mix 120
>>and 220 in the same box.. but that's just me. Code might allow it.. I
>>just don't know.. but it seemed simpler for me to keep them seperate.
>
>
> I've never seen where it was "legal" but my Practical view is that I
> wouldn't do it even if it were allowed.
How will you get 220V without having 110v? 220 basically uses the 110
circuitry anyway. Not saying its legal. But from the point of view of
not mixing voltages it wouldnt make sense. From the point of view of
not mixing breakers it would.
>
> Even up to 60A (ovens) or higher is pretty straightforward. You decide
> what ampacity you need by the nameplate of the device (required to be
> accurate), choose your wire gauge based on your tolerence for voltage
> drop, choose your conduit fill by looking it up in a table OR
> calculation.
>
While what you say is loosely true, your wires are actually sized to
your circuitbreaker or larger. Never smaller. Your CB will be based on
the current you wish to provide and how much is available.
> Nothing about it is especially Difficult, but it Does require attention
> to detail.
>
Only difficult part is getting shocked. Outside of that, screwing down
bolts and running wire through tube is not too tough.
> Always work to your comfort level and call an electrician if any part of
> the job makes you UNcomfortable, preferably before starting it.
>
> My comfort level is, "If I can kill power and the source panel has
> capacity. (space and ampacity) for the given job." YMMV and work within
> your comfort level.
>
true. Consider if you want a permit as well.
--
Thank you,
"Then said I, Wisdom [is] better than strength: nevertheless the poor
man's wisdom [is] despised, and his words are not heard." Ecclesiastes 9:16
On 31 Jan 2006 11:20:00 -0500, DJ Delorie <[email protected]> wrote:
>My inspector's attitude is 100% health and safety - if it's safe,
>he'll pass it, if it's not, he won't. It made it easy to guess what
>would pass.
Your inspector is constrained by the building code adopted by your
jurisdiction. In some states like Florida it is a statewide code with
no local yokel invented rules. They are currently on NEC 2002 and will
be 2005 in July.
On 30 Jan 2006 23:18:55 -0500, DJ Delorie <[email protected]> wrote:
>It might be that all the conductors in a given box have to be on the
>same breaker, though. Ask your local inspector to make sure.
Where did you hear that? It is certainly not an NEC rule.
peterh5322 <[email protected]> writes:
> NEMA 6-15P for 240 volts, 15 amps.
>
> NEMA 6-20P for 240 volts, 20 amps.
For those who don't know, the 20 amp outlet will accept a 15 amp plug,
much like the 20 amp 120 VAC outlets.
[email protected] writes:
> >It might be that all the conductors in a given box have to be on the
> >same breaker, though. Ask your local inspector to make sure.
>
> Where did you hear that? It is certainly not an NEC rule.
I didn't hear it, I was just guessing. My guess was based on the
safety factor - if you shut off a breaker to work in a box, it would
be dangerous if there were other live wires in the box. If each box
had exactly one breaker, shutting off one wire in that box shuts off
all the wires in that box.
My inspector's attitude is 100% health and safety - if it's safe,
he'll pass it, if it's not, he won't. It made it easy to guess what
would pass.
[email protected] (Scott Lurndal) writes:
> It's not a problem to mix 220v and 120v current carrying conductors
> in a raceway (read: conduit), as the potential to ground for any
> single conductor is 120v.
It might be that all the conductors in a given box have to be on the
same breaker, though. Ask your local inspector to make sure.
"Mike Marlow" <[email protected]> writes:
> Are you saying he rejects wiring that is up to code because it does
> not meet his definition of safety?
Well, I've heard stories about inspectors that require more than what
code requires. For example, carpeting. Carpeting is not a health or
safety issue (assuming the underlayment is safe) but I've heard of
inspectors that require it for occupancy, and would fail bare floor.
> Or perhaps even that he accepts things that are not up to code
> because in his opinion they are somehow safe?
No, obviously he requires the house also meet code. There's more to
an inspection than code, though. And there's more to an inspection
than the electrical bits too.
> And... I'll bet he passed it right? What did his "test" prove?
It proves that he doesn't blindly follow the code, and that he's
willing to learn, and that in the end it's HIS responsibility to make
sure the house is safe, not some book's.
> You're wired to code and you can't do any better than that,
Sure you can. Code says 15 amps, I can wire to 20. I have more
outlets than "every N feet". I have GFIs where they're not strictly
required.
"Mike Marlow" <[email protected]> writes:
> > My inspector's attitude is 100% health and safety - if it's safe,
> > he'll pass it, if it's not, he won't. It made it easy to guess what
> > would pass.
>
> I'll bet his attitude is more like, "if it's up to code, he'll pass it".
Well, he told me what his attitude was when we first met, and his
actions backed it up. But, if you know something about my inspector
that I don't, please, let us all know about it.
For example, we were using a type of insulation he was unfamiliar with
it. Code said it was OK, but he also took a bit of it home to see how
it reacted to fire, just in case.
Since our town and state use the national code, I could probably argue
with him about anything that wasn't strictly code, but I'm not that
stupid. He was acting in my best interests, and it was obviously so,
and I was happy about it.
I don't know if anyone has suggested this, using twist lock works great
(better holding = better contact)
Just my $0.02
Frank
rich wrote:
>Hi, All,
>
> Very soon, I will be ordering a table saw, jointer, and maybe a
>planer. Santa was VERY GOOD!!! All will run on 220. My shop has 220
>at the box, at least 2 circuits. The previous owner ran a welder and
>huge compressor, so the amps are there.
>
> I did some wiring 25 years ago, but am a little rusty. I think I
>want junction boxes every 6-8 feet or so around the shop, so I can plug
>in things or move them to a different location. Is there a standard
>plug, like a dryer or oven plug that I should use? Does it matter for
>my shop? I understand I will want to keep the plug to equipment
>distance as short as possible, but would like the ability to plug the
>saw in on one wall, then maybe later on the other wall for a different
>job, or for whatever reason.
>
> Should I run separate conduit for the 220? I have 110 boxes every
>six feet at chest hight currently, and it might be possible to snake
>additional wire down the same conduit, and add a 2nd junction box for
>the 220???
>
> Thank you all for your help and suggestions.
>
>Regards,
>
>Rich.....
>
>
>