Gic mg73bh 415vn 3 phase 4 wire phase failure rotation assymmetry dpco gic mg73bh p the mg73bh 230v is a 3 phase 4 wire voltage relay that will monitor your incoming 3 phase n supply the relay is fully featured with under and over voltage adjustment asymmetry and delay timers and signal led s for all fault conditions p gic mg73bh 415vn 3 phase 4 wire phase failure rotation assymmetry dpco