Efficiency Efficiency (transformers)

Efficiency
Ratio of mechanical output to electrical input
indicated by a percent. In motors, it is the
effectiveness with which a motor converts
electrical energy into mechanical energy.

Efficiency (transformers)
The efficiency of a transformer is the energy
output expressed as a percentage of the energy
input and reflects the losses within the
transformer. For loads between 25% and 150%
of rating efficiencies between 98% and 99.5%
would not be untypical.