PD690 Proving Unit

The PD690 proving unit produces 690V AC/DC to enable voltage indicators to be fully checked. This unit is suitable for indicators with 230V and 415V / 440V AC or DC detection ranges. The PD690 is one of the few proving units to check indicators with ranges above 250V. It can also check Drummond and other filament lamps due to its output being sufficient to illuminate the bulb.