Precautions for High Voltage Flashover Testing of ST-2000 Cable Fault Locator
During high voltage flashover testing, the voltage can reach tens of thousands of volts, so operations must be carried out in accordance with high voltage operating procedures. Special attention should also be paid to the following points:
During high voltage flashover testing, the high voltage test equipment should be operated by professionals. When wiring the instrument, during testing, when changing connections or adjusting the gap distance of the ball gap, be sure to cut off the power, fully discharge the capacitors and cables, and then connect them to the ground wire.
Before testing, the faulty cable should be pressurized and discharged to ensure that there is no discharge phenomenon at each connection point, and the applied voltage has caused the fault point to flashover and discharge, then start the instrument test.
When using the flashover method to test high resistance faults, the user should not perform other operations on the computer, and *avoid selecting the "low voltage pulse" state for high voltage flashover testing. The test instrument connection wires should be kept away from high voltage lines.
Correct grounding: connect the high voltage transformer (T2) high voltage tail, the operation box (T1) ground wire, and the current sampler (JS) ground terminal to the same point as the cable armor (single point grounding). All connection points must not have arcing to ensure successful testing and the safety of equipment and personnel.
For the safety of the test instrument, during flashover testing, the working menu must be selected in the impulse flashover or direct flashover state. If the pulse state is incorrectly selected for high voltage flashover testing, it may damage the low voltage pulse circuit inside the test instrument.
During testing, avoid using AC power to charge the front-end (flashover tester) and computer, so that they are completely isolated from the AC power supply under test.
After high voltage flashover testing is completed, the capacitors and cables must be repeatedly discharged before using the low voltage pulse method to re-test the cable.
Note: The above information and technical parameters are compiled and released by Yangzhou Darui Electric Co., Ltd.
