What should I do when the temperature of the current transformer is abnormal?

1. Preliminary judgment
1. Observe the phenomenon: Carefully observe the appearance of the current transformer to see if there are obvious signs of overheating, such as surface discoloration, smoke, burnt smell, etc. At the same time, pay attention to whether the indications of the ammeter, power meter and other instruments are normal. If the ammeter indicates abnormally or the power meter indicates inaccurately, it may be related to the overheating of the current transformer.
2. Check the operating environment: Check whether the ambient temperature of the current transformer is too high and whether the ventilation is good. If the ambient temperature is too high or the ventilation is poor, the current transformer may not dissipate heat well, causing abnormal temperature rise.
2. Specific inspection
1. Check the primary side wiring: Check whether the primary side wiring is firm, loose, poor contact or oxidation. Looseness or poor contact will cause additional heat loss when the current passes through, causing the temperature to rise. If the wiring is found to be loose, the wiring should be tightened immediately; if the terminal is severely oxidized, it should be cleaned or replaced.
2. Check the secondary side circuit: Check whether the secondary side circuit is open or short-circuited. When the secondary side is open, the primary current is all used for excitation, which will cause the core magnetic flux density to increase sharply and cause the core to overheat. If the secondary side is found to be open, measures should be taken immediately, such as using a short-circuit wire to short-circuit the secondary circuit to prevent high voltage from being generated.
3. Check the load condition: Check whether the load connected to the current transformer is too large. Overload operation will increase the core magnetic flux density of the current transformer, causing the core to overheat. If the load is too large, the load should be appropriately reduced, or the current transformer should be replaced with a device with a larger rated capacity.
4. Check the insulation condition: Use an insulation resistance meter to measure the insulation resistance of the current transformer to check whether its insulation is good. Aging or damage to the insulation will cause leakage and heat up the equipment. If the insulation resistance value is lower than the specified value, consider replacing the current transformer.
5. Check the oil level and oil quality of the oil-immersed current transformer: For oil-immersed current transformers, check whether the oil level is normal and whether there is seepage or oil leakage. If the oil level is too low, the insulating oil should be replenished in time; if the oil quality deteriorates, the oil quality should be tested and replaced with new oil if necessary.
III. Treatment measures
1. Reduce the load: If it is determined that the temperature abnormality is caused by overload, the load should be reduced to below the rated load as soon as possible, and the operation of the current transformer should be continuously monitored.
2. Strengthen heat dissipation: If the ambient temperature is too high or the ventilation is poor, measures should be taken to strengthen heat dissipation, such as adding ventilation equipment, cleaning the heat dissipation channel, etc.
3. Repair or replace parts: According to the inspection results, repair or replace the faulty parts found. Such as repairing the terminal, replacing damaged insulating parts, replenishing or replacing insulating oil, etc.
4. Shutdown for maintenance: If the temperature of the current transformer is too high, or even smokes and catches fire, the relevant power supply should be cut off immediately to prevent the fault from expanding. After the power outage, the current transformer should be fully inspected and repaired.
IV. Follow-up measures
1. Record the fault situation: Record the phenomenon, cause and treatment measures of the abnormal temperature of the current transformer in detail for future analysis and reference.
2. Strengthen daily maintenance: Regularly inspect the current transformer, use an infrared thermometer to monitor the temperature of the equipment, and promptly detect abnormal heating. At the same time, regularly perform insulation tests, oil quality tests and other maintenance work to ensure that the equipment is in good condition.