Back Electromotive Force, Back EMF or Counter Electromotive Force, is the EMF that pushes against the current that induces it. In other words, it is the voltage that occurs in electric motors where there is relative motion between the armature of the motor and the magnetic field from the motor. Such Inductive loads are damaging to Reed Switches and will require Contact Protection to allay the effects of back EMF.
Counter-electromotive_force (Wikipedia)
In electromechanics, the counter-electromotive force (also called counter EMF, CEMF or back EMF), is the opposing electromotive force (EMF) caused by a changing current. The changing current leads to a changing magnetic field, and hence induces a EMF in the circuit by Faraday's law of induction.
Synonyms
Counter Electromotive Force
