Operation, maintenance and management of residual current transformers

- Sep 09, 2020-

(1) After the residual current transformer is put into operation, the user shall establish operation records and corresponding management systems

(2) Electricity management personnel should carry out energization and tripping test of the residual current transformer at least every month, that is, press the test button to check whether the residual current transformer is reliable. Whenever a lightning strike or other reasons cause the residual current transformer to operate, it should be checked and a trip test should be performed. In the peak season of rural power consumption, the number of test trips should be increased; the out-of-service residual current transformer should be tripped and tested once before being used.

(3) In order to fully grasp the operating status of the residual current transformer, the residual current transformer should be sampled and tested regularly (such as during the annual safety inspection).

(4) The testing of residual current transformers should be organized by the full-time safety management personnel of the power supply station under the guidance of the local power department. The items for regularly testing the operating characteristics of the residual current transformer should include the residual operating current value, the remaining non-operating value, and the breaking time.

(5) The test content of the low-voltage power grid includes the ground unbalanced leakage current of the protected power grid, the protected power grid and various loads, the insulation resistance value of the motor, the neutral point leakage current of the low-voltage side of the distribution transformer, and various electricity consumption The grounding resistance of the equipment protective grounding device. The test data is compared with the last test result for comprehensive analysis. Those who fail the test or have major defects should be repaired or replaced in time.

(6) The operation characteristic test of the residual current transformer and the simulated leakage operation test of the protection power grid shall be performed by professionals with special measuring instruments qualified by the relevant state departments. It is strictly forbidden to use the phase line to directly touch the grounding device to conduct the simulated leakage action test of the protection grid.

(7) The trial jump, test, setting and test process must be recorded by a dedicated person, and the recorded items and data must not be confused or wrong, for reference in future operation analysis.

(8) If an electric shock accident occurs within the protection range of the residual current transformer, the operation of the protector should be checked, the reason should be analyzed, and the accident report should be written. Note: Before the power department sends someone to inspect, protect the site and not modify the protector site.

(9) If the user intentionally causes the protector to refuse or misoperation, he should be given criticism and education and warning. Those who do not repent after the criticism and education can temporarily stop the household's electricity consumption.

(10) After the residual current transformer is operated, if the cause of the accident is not found after inspection, it is allowed to test power once. If it is operated again, the cause should be found out to find out the fault, and the power shall not be continuously forcibly transmitted. Unless it is confirmed that the residual current transformer itself is faulty after inspection, it is strictly forbidden to remove the residual current transformer without permission and force the power supply.

(11) The maintenance of the residual current transformer should be carried out by professionals. If there is any abnormal phenomenon during operation, an electrician should be found to avoid expanding the scope of the accident.

(12) The power supply station should be equipped with common test meters and a certain number of spare protectors. The operation of the residual current transformer should be analyzed regularly, and the residual current transformer that cannot be used normally should be replaced in time.https://www.ctsensorducer.com/