The meter adopts digital tube display equipped with fully enclosed shell. Use more secure. This meter can measure 50Hz/60Hz 12V- 50Hz/60Hz 400V AC voltage (average). Streamline design the meter adopts the resistance capacity step-down power supply. Connect directly on the zero line and the line of fire no additional power supply. The touch design when the power supply is not stable/or poor contact header will not burn. Life design. LED working current control within 20 ma greatly extended the life of the LED. Global measuring ac voltage range the most widely used after rectifying step-down way first and avoid the instability of rectifier diode error brought about by the pressure drop. Defect is rising costs (increase CBB filtering capacitor). Parameters: Working voltage: AC 12~400V - communication. Accuracy/error: 1%. Speed: 200 ms/or times. Application: AC 220V mains voltage test. The voltage of 220V generator monitoring. Inverter output of electricity monitoring. Other AC circuit voltage test.