In order to inspect and ensure the installation quality of the cables, before the power supply and commissioning, on-site AC or DC withstand voltage tests should be conducted on the cables. Before and after the withstand voltage test of the wires and cables, the following safety measures should be taken.
1. Cable inspectors must abide by the general procedures for electrical high-voltage tests.
2. Before conducting any test work, all test personnel must wear the prescribed protective gear; otherwise, they are not allowed to work.
3. All electrical tests for all cables should be conducted in the designated test area. It is strictly prohibited to conduct tests outside the test area, across the area, or by using temporary lines.
4. All safety indication systems: door switches, alarm bells, signal lights, etc., must be kept functioning properly. Any malfunction should be repaired promptly.
5. When the test staff are working in the test area, they should first cut off the power supply. The door of the test area should always remain open. A warning sign reading “The test area is electrified. Do not enter” should be hung on the door.
6. The metal partitions in the examination room, the enclosures of electrical equipment, and the protective devices must all be securely grounded. The grounding resistance should not exceed the requirements stipulated in the relevant standards.
7. For all electrical equipment and on the floor of the operation console area, insulating rubber mats must be laid to prevent electric shock.
8. Warning signs such as “High Voltage Hazard” should be placed on the barriers of the test site. Before the test personnel enter the test area for work, they must pay attention to the high voltage signal lights. They are not allowed to enter the test area when the signal lights are on.
9. When removing the protective layers (hemp sheath, steel tape, lead skin) at both ends of the cable, be sure to prevent the tools (knives, pliers, scissors) and the steel tape and lead skin from causing injury to people. The waste materials removed should be promptly cleared out of the testing area.
10. The length of the insulation sheaths at both ends of the cable should be measured to meet the test requirements. It should not be too long. Be sure not to damage the overall insulation near the lead sheath.
11. After confirming that the wiring is error-free and error-free, and after the clearing signal is given to everyone in the examination room, the main examiner should close the door and give the signal to start the power supply.
12. After the cable power transmission test, wait for 1 to 2 minutes. Only then can you leave if there is no breakdown or discharge phenomenon in the cable.
13. When lighting the blowtorch, it is essential to keep away from the oil depot and cables. When inflating the blowtorch, the pressure should not be too high. Before refueling, the blowtorch must be extinguished. When using the blowtorch, be careful to prevent burns.
14. Before conducting the cable test, it is essential to thoroughly check whether the test equipment, instruments, and other measurement lines are in good condition, and ensure that the voltage regulator is at zero position.
15. For the high-voltage disconnect switch, it shall not be closed during testing. After the test is completed, it must be disconnected and checked by the team leader to ensure there are no errors.
16. During the entire pressure test process, the test personnel must not leave their posts without permission. Pay attention to the security precautions around the test site to prevent anyone from entering the test area by mistake.
17. Once the pressure test is completed, immediately turn off the power switch and issue the signal to release the electrical test (electric bell, electric horn).
18. During the test, keep a close eye on the operation of the test subject, the test equipment and instruments. If any problems are detected, immediately stop the test. After the problem is resolved, resume the test.
19. During the test process, if it is necessary to enter the test area to change the wiring, after the power is cut off, a resistor-equipped discharge rod must be used to fully discharge the tested cable to the ground, eliminating static electricity and confirming that there is no electricity. After the entire test is completed, do not immediately remove the grounding wire or touch the cable core with your hands. Instead, short-circuit the three phases to the ground for discharge and maintain this state for a certain period of time. Only after it is confirmed that there is no electricity should you touch it with your hands. It is strictly prohibited to touch the test cable that has not been discharged or tested.
20. The test equipment and instruments should be managed and operated by designated personnel. Before obtaining the consent of the manager or the station chief, no one is allowed to tamper with or dismantle the equipment or safety devices at will.
21. Equipment, instruments and meters should be kept clean and properly calibrated on a regular basis to ensure accurate readings.
22. When working inside or outside the test area, be careful of the rolling cable reels and the moving cranes.
23. After the test is completed or the power is turned off, all switches should be disconnected, the test room door should be opened, and the pressure regulator should be reset to zero.
Post time: Jun-24-2026