My table saw motor has gone bad. It was like the blade was binding on
something, and came to a fast stop when switched off. Then there was
significant electrical smoke I had to air out. I unplugged it for a day.
Now when I plug it in and start it it seems as if there is a series of jerky
electrical resistance spurts, accompanied by a pulsating noise. Like the
motor is firing against itself - resisting its own powered rotation by
sending quick spurts of electricity power in the wrong direction. Rough,
brief, jerky rotation.
It came with a complete manual listing all parts including a full motor, but
also has a separate exploded parts illustration of just the motor.
Unfortunately it's out of warranty. So can I suspect to replace any parts,
without having to replace the whole motor?
table saw motor binding electrical smoke resistance noise jerky
Mastercraft 55-6886-6 10" 15A 120V 60Hz 3.0 hp max 5000 rpm no-load speed
http://www.canadiantire.ca/browse/product_detail.jsp?FOLDER%3C%3Efolder_id=2534374303523072&bmUID=1238874397130&PRODUCT%3C%3Eprd_id=845524443277381&assortment=primary&fromSearch=true
On Sun, 5 Apr 2009 11:05:46 -0500, "Jim" <[email protected]> wrote:
>
>"Tom Veatch" <[email protected]> wrote in message
>news:[email protected]...
>> On Sat, 4 Apr 2009 17:05:56 -0400, "bentley" <[email protected]> wrote:
>>
>>>Mastercraft 55-6886-6 10" 15A 120V 60Hz 3.0 hp max 5000 rpm no-load speed
>>
>> Only way to know for sure is to pull the motor and take it to your
>> friendly neighborhood motor shop for a checkup.
>>
>> I will say that the "15A 120V...3.0 hp" listing on the motor is super
>> optimistic at best. About the best power you can hope to get out of a
>> 15A 120V input is in the neighborhood of 1.5 to 2.0 HP. Getting 3HP
>> out of those inputs would violate the hell out of the 1st Law of
>> Thermodynamics. You ain't gonna get more out than you put in.
>>
>> Tom Veatch
>> Wichita, KS
>> USA
>
>That rating is more than likely the maximum horsepower. The manufacturer is
>just taking advantage of the poor folks who don't understand how alternating
>current works.
It has nothing to do with alternating current. It has everything to
do with marketeering, bordering on fraud. These numbers often are the
stalled rotor current times the source voltage to calculate HP (1HP ~=
750W). If course this number is meaningless. No, I don't pretend
that my shop vac is 3.5HP either. ;-)
>I agree, the actual horsepower is more like 1.5 (that is the average value).
No, the actual horsepower is more like .5HP, or maybe even lower.
Check the line cord for an eye opener.
"Tom Veatch" <[email protected]> wrote in message
news:[email protected]...
> On Sat, 4 Apr 2009 17:05:56 -0400, "bentley" <[email protected]> wrote:
>
>>Mastercraft 55-6886-6 10" 15A 120V 60Hz 3.0 hp max 5000 rpm no-load speed
>
> Only way to know for sure is to pull the motor and take it to your
> friendly neighborhood motor shop for a checkup.
>
> I will say that the "15A 120V...3.0 hp" listing on the motor is super
> optimistic at best. About the best power you can hope to get out of a
> 15A 120V input is in the neighborhood of 1.5 to 2.0 HP. Getting 3HP
> out of those inputs would violate the hell out of the 1st Law of
> Thermodynamics. You ain't gonna get more out than you put in.
>
> Tom Veatch
> Wichita, KS
> USA
That rating is more than likely the maximum horsepower. The manufacturer is
just taking advantage of the poor folks who don't understand how alternating
current works.
I agree, the actual horsepower is more like 1.5 (that is the average value).
Jim
On Sat, 4 Apr 2009 17:05:56 -0400, "bentley" <[email protected]> wrote:
>Mastercraft 55-6886-6 10" 15A 120V 60Hz 3.0 hp max 5000 rpm no-load speed
Only way to know for sure is to pull the motor and take it to your
friendly neighborhood motor shop for a checkup.
I will say that the "15A 120V...3.0 hp" listing on the motor is super
optimistic at best. About the best power you can hope to get out of a
15A 120V input is in the neighborhood of 1.5 to 2.0 HP. Getting 3HP
out of those inputs would violate the hell out of the 1st Law of
Thermodynamics. You ain't gonna get more out than you put in.
Tom Veatch
Wichita, KS
USA