Voltage equation for Dc shunt generator, Eb = V + Ia*Ra V = Ish*Rsh Ish = 200/100 = 2 A Eb = V + Ia*Ra 20 = Ia*Ra Ia = 20/0.2 = 100 A I = 100 - 2 = 98 A
Buchholz relay is used for protecting transformer against incipient or internal faults. Buchholz relay is a gas-actuated relay installed in oil immersed transformers for protection against all kinds of faults.