BHP vs HP

[gh0st]

There seems to be a trend to size the electrical distribution based on a motor's BHP versus its HP/FLC. From what I understand, the BHP is the mechanical output of the motor and may not necessarily represent the demand of the motor.

Its been described to me as something to be like a disconnect switch. Motor HP rating have standard sizes similar to disconnect switches...and is represented as such in Table 430.250. The BHP is apparently a better indication of the motor's true load and should be used for sizing the electrical distribution. I can't find any white papers that support this. Also, I still hold firm that 430.6 should be upheld.

Do you agree? TIA.

 

[retirede]

Motor HP ratings are available mechanical shaft HP at rated output. I’ve always used BHP to describe the power required by a load.

See NEMA standard MG-1.

 

[Besoeker3]

We use motor output power for kW. It's pretty much the universal standard.

 

[drcampbell]

"Brake" horsepower was initially invented to distinguish the amount of net useful power an engine delivers from the gross power it develops, some of which is consumed by ancillaries such as the alternator, water pump, power steering pump and muffled exhaust system.

Horsepower - Wikipedia

en.wikipedia.org

But electric motors don't need ancillaries, so the distinction is meaningless. There's just input power and output power. When wiring one, all that's important is the electric power it consumes. Mechanical power is important when sizing the motor to the machine it's driving.

And it would sure save a lot of chaos & confusion if Americans (and Liberians & Myanmarians) would use watts for the both of them.

 

[Besoeker3]

"Brake" horsepower was initially invented to distinguish the amount of net useful power an engine delivers from the gross power it develops, some of which is consumed by ancillaries such as the alternator, water pump, power steering pump and muffled exhaust system.

Horsepower - Wikipedia

en.wikipedia.org

But electric motors don't need ancillaries, so the distinction is meaningless. There's just input power and output power. When wiring one, all that's important is the electric power it consumes. Mechanical power is important when sizing the motor to the machine it's driving.

And it would sure save a lot of chaos & confusion if Americans (and Liberians & Myanmarians) would use watts for the both of them.

Or SI. International System.