GDDO-20C AC / DC Electric Meter Calibration Device ti wa ni lilo lati ṣe awari aṣiṣe ipilẹ ti ọpọlọpọ awọn ohun elo itanna igbohunsafẹfẹ agbara ni awọn eto agbara, pẹlu voltmeter, ammeter, wattmeter, ohmmeter, ipele kan & awọn mita agbara AC ipele mẹta (aṣayan) ati aṣiṣe ipilẹ ti DC folti-mita ati ammeter.