Answer / a.p.nanjappa

Generally manufacturer provide only 2NO+2NC Contacts.But
the client need more application such as remote
indications,interlocks,other switching operations photocell
camera,DCS,.....which need more contacts to represent CB
conditions. this is done with multiplication relay.

Answer / rajesh

the purpose of breaker contact multiplication relay is to
get NO & NC contacts, which can be used for breaker on and
off indication in remote places.

Answer / sourav pramanik

contact multiplication relay are used for incresing contact...let there are so many on off switch ,alarm are to be activated..but main relay contacts are very less..so to increase contact we use cmr.

Answer / rbkrishnan

And there are three coil A,B,C are used in that .my
question is what are the coil pickups during breaker on &
off

Answer / rohantamhane

A,B,C, coil in the breaker one coil is closing coil and two
coil for tripping coil for Back up proteaction

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