What_is_mean_by_negative_dc_voltage? why we use -48v except
+48v in DC power supply systems.

Answer Posted / er. ankush miglani 9718151073

IF WE CONNECT THE +VE POLARITY TO THE EARTH AND -VE TO THE
EQUIPMENT THE VOLTGE IS CALLED -VE DC VOLTAGE.
THE POSITIVE POLARITY ACQUIERS THE CORROSION VERY QUICKLY
AND TO MAINTAIN THE VOTAGE OF THE DEVICE UNDER
SPECIFICATIONS IT IS DONE.

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