Q1: What is a volt amp meter?
A1: A digital volt amp meter is a high-precision, low-consumption, low-cost, portable, handheld, dual-channel input measuring instrument, specially designed for measuring voltage, current and phases on-site.
Q2: How a volt amp meter works?
A2: The volt-ampere meter adopts the clamp conversion method to input the measured current, so there is no need to disconnect the measured line during measurement. When measuring the phase between U1-U2, the two input circuits are completely insulated and isolated, thus completely avoiding the short circuit of the measured line caused by miswiring and burning the measuring instrument. This is the working principle of volt ammeters.
Q3: What can a volt amp meter do?
A3: When the circuit under test is not open, the volt ammeter can simultaneously measure two AC voltages, currents, phases between voltages, phases between currents, phases between voltages and currents, frequency, phase sequence, active power, reactive power, apparent power, power factor, etc., the volt amp meter can also identify the transformer wiring group, inductive and capacitive circuits, test the secondary circuit and bus differential protection system, read the phase relationship between the CTs of the differential protection groups, and check the watt-hour meter wiring and line equipment.
Tips: Phase relationship between voltage and current
The phase difference of voltage and current depends on the nature of the load, and the voltage and current of a purely resistive load are in phase. The current phase is a physical quantity that reflects the state of alternating current at any moment. The magnitude and direction of alternating current change with time. Phase voltmeters are used to measure the phase between voltage and current.