Answer / ss

there is chances of failure of ac suply but dc suply cant
fail because it is fed from batery bank.

Answer / maddoxx

in control and protection ckt very small current is require in relays ,cb etc .The panel is placed far from the work place.so if we use small ac current there may be chance of interference by communiation frquency and signaling it also produces noise which can too interfere in other sognalling freq. so dc current there is no frequency and we can increase the accuracy and sustain the strenth of signal coming to controlling panel.

Answer / vijay balu raskar

DC is constant & continuous source. For protection & control it is suitable. Also, having quick responce without disturbance & variation. In ac opposite of dc.

Answer / tahirwasim10

Protection of a system is very necessary factor which
require fast response during faults. For protection of a
power system the D.C used instead of A.C because there are
many problems in A.C ( quantities variation problems, slow
response problems etc).

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