Why is DC use instead of AC for protection and control
circuits?
Answer Posted / 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.
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