Reed Relays and
Electronics India Limited
Manufacturer of Reed Switches, Reed Sensors and Reed-based products
Reed Relays and Electronics India Limited Incorporated in 1971

Back EMF

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

Counter-electromotive force (counter EMF, CEMF), also known as back electromotive force (back EMF), is the electromotive force or "voltage" that opposes the change in current which induced it. CEMF is the EMF caused by magnetic induction (see Faraday's law of induction, electromagnetic induction, Lenz's law).

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