## Power output P_{2} (watt)

Electric motors transform the electrical energy which they take from the power supply network into mechanical energy.

This consumed energy is called power input P_{1} (watt), and the power delivered at the drive shaft is the power output
P_{2} (watt.

** P _{1} = U x I x cos j (watt)
P_{2} = P_{1} 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.

**P**

_{2}= M x n : 9550**P in kW, M in Nm, h in 1/min**