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Hi Sunking, brian_,Yes essentially Input Power so I could calculate how much input power input required for 10 HP

Yes I had to use torque and rpms to extrapolate Continuous HP and it worked out to 4.14 HP. I also extrapolated 10 HP power by using the constant 1020 watts /HP x 10 = 10,200 watts, then factored out current of 222 amps peak.

So where have I gone wrong? Pretty sure I have made an incorrect assumption. I calculated current required based Input Power of 222 amps, so a 200 to 250 amp controller would work. However the manufacture recommends a 400 Amp controller with the motor. OK it occurred to me manufacture might be specifying Stall Current rather than based on 10 HP wattage.

I know peak power values of a motor is a Thermal Limit so max power might be debatable if more cooling factors in. Manufacture did not publish Peak Power watts for motor @ 10 hp.

You are throwing me off converting on mechanical power. In my minds eye Input Power is what a designer needs to know right?

...

Sun... You know units, right? Like inches and centimeters. Both in. & cm are units of length, or distance. So you have a wire 4 inches long, that same wire is also 10.16 cm long. No difference in the length, just a difference in units of measure. 4 inches = 10.16 cm. Or a conversion factor of one inch = 2.54 cm.

The same is true for power. Both watts and horsepower are units of measure for power. It does not matter in what form the power is, like electrical, or mechanical, or radiant, or average, or peak. Both hp & watts measure the same thing: Power. One horsepower = 746 watts. Here's a good review of power and its units of measure.

https://en.m.wikipedia.org/wiki/Power_(physics)

Efficiency is defined as the power output / power input * 100%. Of course you use the same units of measure for the numerator and denominator. So eff = watts out / watts in * 100%. Or eff = hp out / hp in * 100%.

Also, beware of ratings. Rarely will rated power translate to useful efficiency values. Manufacturers often use worst case tolerance limits on nameplates, or nominal values. And for a motor, peak power (output power) may not be a thermal limit at all.

And the controller current limit is just that. It does not relate to motor stall current or motor rated power. It is the same "5hp rated" motor if I use a controller having a 200, 400, or 1000 ampere current limit.

The peak power output for a motor and controller combination typically occurs at the point where at full throttle the controller transitions to current limit.

Regards,

major