There is a sampling circuit in the measured capacitor branch that samples the voltage and current of the measured capacitor. The output terminals of the sampling circuit are respectively connected to amplification circuits. The voltage signal output from the voltage amplification circuit and the current signal output from the current amplification circuit are used to output phase difference signals through a phase detector. After passing through an A/D converter with the voltage signal and current signal, they are input to the CPU for calculation to obtain the measured capacitor value. Due to the use of a mobile current sampling unit, capacitance values can be directly measured without removing the connecting wires.
When measuring single-phase parallel capacitors, the instrument panel should be wired, and all four wires should be connected. Insert the current clamp (internal current clamp can also be used). Choose the appropriate testing method and enter the testing phase.
Attention during the testing process:
(1) Connect one end of the test voltage cable to the yellow, green, red, and black terminals corresponding to the above test mode;
(2) Insert the test current signal cable into the instrument ;
(3) Connect the 220V power cord of the testing instrument and turn on the power switch;
(4) Clamp the test voltage cables onto the connecting busbars of the two poles of the tested capacitor group, and clamp the clamp current sampling meter at the sleeve of the single capacitor to be measured;
(5) After booting up, select the testing mode for the capacitor to be tested, and then enter the testing mode;
(6) After entering, the screen displays the first screen power on display. Move the cursor to the "capacitor" position, long press the "confirm" button, and start measuring after hearing the beep sound. Each beep sound is a measurement cycle (about 2 seconds). The measurement results are directly displayed on the screen;
(7) Remove the clamp ammeter and clamp it onto another capacitor to be measured until the measurement of that phase is completed. In three-phase mode, data from three capacitors will be generated in one wiring;
(8) After the test is completed, cut off the power and restore all switches on the panel to their pre test state, and remove all wiring.