DIY Knowledge

Power output P2 (watt)

Abgabeleistung P2 (Watt)

Potencia útil

Puissance débitée

Electric motors transform the electrical energy which they take from the power supply network into mechanical energy.
This consumed energy is called power input P1 (watt), and the power delivered at the drive shaft is the power output P2 (watt.

P1 = U x I x cos j (watt)
P2 = P1 x I x h (watt)

Unfortunately, this conversion process is accompanied by power losses, and their efficiency ratio n always has to be less than 1. The power factor cos j of universal motors is approximately 0.95 to 0.98 and can therefore be neglected. The delivered power is measured by mechanical braking.

P2 = M x n : 9550
P in kW, M in Nm, h in 1/min