... 3. Full digital, high stability I. IntroductionDF~301 three~phase meter takes single chip as kernel, adopts three separate voltage channels ... . with seven functions: voltmeter, ammeter, phase meter, phase sequence meter, frequency counter, power meter, power factor meter.2. Display vector figures with six angles ... power supply: 85-265Vac, 0.8A, power≤8VA DF-301 Portable Three-Phase Meter