1、 The situation reflected by regulatory agencies

When the power is turned on, the electromagnetic switch is turned on, and the voltage regulator is turned on, the voltage regulator will make a heavy sound. This may be due to the 220V voltage regulator being connected to the 380V power supply incorrectly. If the current reading is abnormal at this time, it may be due to the voltage regulator not being at zero position, or a short circuit or similar short circuit on the output side. Forgetting to remove the grounding rod is common.

2、 The situation reflected by the voltmeter

(1) The voltmeter indicates. After the power is turned on, the voltmeter immediately gives an indication that the voltage regulator is not at zero position. If the voltmeter has a large indication and a sound, it may immediately smell it.

(2) The voltmeter shows no indication. After power on, the voltage regulator meter shows no indication. This may be caused by poor contact of the carbon brush in the autotransformer, a malfunction in the voltmeter circuit, or a broken circuit in the transformer measuring coil (or transformer input coil).

3、 What happens during the boosting process

(1) During the boosting or continuous testing process, internal discharge of the current limiting resistor may occur, which may be caused by water shortage or insufficient water in the tube. Sometimes there may be arcing on the outer surface of the pipe, which may prevent it from returning to the station, or the straightness may be caused by excessive water resistance, short pipe, or dirty surface.

(2) During the boosting process, the voltage rises slowly and the current rises sharply. This may be caused by a short circuit or similar short circuit situation of the tested device, or it may be caused by the tested device's excessive capacity or proximity to resonance.

(3) If the current decreases as the voltage regulator increases, the voltage remains basically unchanged or shows a downward trend. This may be due to excessive testing load and insufficient power supply capacity. In this case, please try using a high-capacity power supply. Otherwise, it may be caused by waveform distortion.

(4) During the boosting process, as the adjustment handle of the vortex regulator moves, the output voltage rises unevenly, resulting in a saddle shape, also known as the "N-shaped curve", as shown in Figure 4-13 Exhibition. This is caused by series resonance resulting from the matching of the leakage reactance of the rolling shift regulator with the capacitance reactance of the load capacitor. In this case, the problem can be solved by increasing the current limiting resistor or changing the circuit parameters.

4、 The situation reflected by the tested equipment

The tested equipment passed the withstand voltage test, but was found to have been broken down after the test. This may be due to the negligence of the testing personnel, who forgot to lower the voltage after testing and turned on the switch.

Wuhan UHV specializes in the production ofseries resonance (also known as AC withstand voltage test equipment)and has been engaged in the electrical measurement industry for many years. Its products have first-class quality and welcome customers to come and purchase.