Electrical Current Transformer explosion prevention measures

(1) Check whether the lead connector in the primary terminal of the transformer is in good contact

The lead joints of the primary terminals of the Electrical Current Transformer must be in good contact, and the contact area must be maintained sufficient to prevent the Electrical Current Transformer from overheating failures. The L2 terminal and the expander cover should be connected to the same potential to prevent potential suspension. In addition, there should be anti-rotation measures for the crucible drawn from the secondary line to prevent the internal lead from twisting due to external operations.

(2) The reason for the abnormal test value should be found out

When the tg value of the dielectric loss factor measured before and during operation is abnormal, the tgδ and the temperature should be analyzed comprehensively, or the test voltage rises from 10kv to Um/root3, and the tgδ increment exceeds ±0.3%, it should be withdrawn from operation. . When the result of chromatographic analysis is abnormal, it is necessary to follow a comprehensive analysis to investigate its growth trend. If the data grows rapidly, attention should be paid. Eliminate the accident in the bud.

(3) Keep the busbar differential protection in normal operation

In order to avoid the breakdown of the capacitor core at the bottom of the Electrical Current Transformer to expand the scope of the accident, attention should be paid to the installation direction of the primary terminals L1 and L2 and the polarity connection of the secondary winding to ensure the normal operation of the busbar differential protection. run

(4) Check the short-circuit current

According to the development of the power grid, pay attention to checking and calculating the short-circuit current at the location of the Electrical Current Transformer. When it exceeds the dynamic thermal stability current value of the transformer nameplate, it should be replaced in time.

(5) Jiban carries out online monitoring and infrared temperature measurement

At present, the online monitoring projects carried out by Electrical Current Transformer mainly include: measuring the capacitance and dielectric loss factor tgδ of the main insulation and measuring the insulation resistance and dielectric loss factor tgδ of the final screen insulation. Test experience shows that it is effective for detecting insulation defects. For infrared temperature measurement, some units are already conducting it. The existing test results show that it is effective for detecting the looseness of the internal joints of the Electrical Current Transformer, but it still needs to accumulate experience.