Well, I asked about this once. I was told that the buzzword was peak HP. Which we all know there is no real standard to measure for electric motors. You know, the inrush current when the motor starts is 37A.
37X120=4440W and at 750W/HP that is 5.92HP
So it is 6HP.
A completely worthless number as far as power output. But, they don't say the motor puts out 6HP. They just say 6HP, not defining that that is the peak electrical input power when the motor starts.
Kind of dishonest, but that's marketing for you.
