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Discussion Starter · #1 · (Edited)
Hi

Installing at 15 HP motor (capacity), actual running conditions will be 12.25 BHP

Power : 15 HP
Efficiency : 85%
Power Factor 85%
Voltage : 600V

3 ph Amps 15A

In this case 12 AWG seems ok for both HP and BHP but is it ok to size conductors with BHP or doesn't it have to be done with full potential HP capacity?
 

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You guys in Canada don't have to size to a table like we do?
For non continuous duty we do (Table 27).. Otherwise conductor size minimum is 125% of FLA, plus voltage drop... Which, based on the OPs info, he should be ok (15 amps*1.25=18.75 amps and #12 is good for 30 amps)...
There is a table for motor currents (Table 44 - 3 phase and Table 45 Single Phase), but the name plate would definately trump the tables...
 

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What does BHP mean?
Brake Horsepower.

From Wiki:

Brake horsepower (bhp) is the measure of an engine's horsepower before the loss in power caused by the gearbox, alternator, differential, water pump, and other auxiliary components such as power steering pump, muffled exhaust system, etc. Brake refers to a device which was used to load an engine and hold it at a desired rotational speed. During testing, the output torque and rotational speed were measured to determine the brake horsepower. Horsepower was originally measured and calculated by use of the "indicator" (a James Watt invention of the late 18th century), and later by means of a De Prony brake connected to the engine's output shaft.
More recently, an engine dynamometer is used instead of a De Prony brake. Although the output delivered to the driving wheels is less than that obtainable at the engine's crankshaft, a chassis dynamometer gives an indication of an engine's "real world" horsepower after losses in the drive train and gearbox.

Pete
 

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Brake horsepower... It is the measure of an engine's horsepower before the loss in power caused by the gearbox, alternator, differential, water pump, and other auxiliary components such as power steering pump, muffled exhaust system, etc.
Could you be more precise.:)

I actually thought that what is was, but wasn't sure.

I also didn't know what Brake HP meant, thanks for the explanation.
 

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Could you be more precise.:)

I actually thought that what is was, but wasn't sure.

I also didn't know what Brake HP meant, thanks for the explanation.
I didn't copy as much as Pete did from Wikipedia.. :( lol.. I know it can be editted and not trusted by some, but here is Wikipedia's link..
http://en.wikipedia.org/wiki/Horsepower

There are a half a dozen different terms of horsepower, where they are measured and what they mean..
 
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