Transformer Testing & Maintenance | Complete Inspection Guide
Transformer testing, inspection, and maintenance are essential tasks to ensure normal operation and extend the service life of transformers. Below are some recommended steps:
Visual Inspection: Regularly inspect the transformer's exterior, including the enclosure, cooling system, and oil tank. Ensure the enclosure is intact, free from corrosion, damage, or leakage.
Insulation Resistance Testing: Use an insulation resistance tester to check the transformer's insulation system. Verify that the insulation resistance values meet specified standards to ensure the insulation is in good condition and prevent insulation breakdown.
Oil Quality Check: Regularly inspect the quality of the transformer oil, including oil level, color, odor, and contamination level. Replace the oil promptly if any abnormalities are detected to maintain its effective insulation and cooling performance.
Temperature and Vibration Monitoring: Use an infrared thermometer to measure temperatures at various parts of the transformer, ensuring they remain within normal operating limits. Use a vibration analyzer to assess the transformer's vibration levels and evaluate the mechanical running condition.
Temperature Measurement: Utilize tools such as infrared thermometers to measure temperatures at different locations on the transformer, ensuring they do not exceed the designed temperature limits.
Insulation Resistance Test: Employ an insulation resistance tester to measure the insulation resistance of the transformer and assess whether the insulation condition is sound.
Winding Resistance Test: Use a resistance tester to measure the resistance values of the transformer windings to identify potential issues such as short circuits or poor connections.
Flux Detection: Use a flux detector to measure the distribution of magnetic flux in the transformer and determine if there is any flux skewing or uneven flux distribution.
Earth Voltage Test: Use a multimeter or similar instrument to test the voltage from each phase winding of the transformer to ground, ensuring voltage balance.
Load Testing: Connect a load to test the transformer’s output voltage and load capacity, verifying that its performance meets normal operating requirements.
Comprehensive Testing: Where possible, perform comprehensive tests, including withstand voltage tests, partial discharge tests, and short-circuit impedance measurements.
Regular Maintenance: Develop a regular maintenance schedule based on the transformer's usage and requirements. This includes cleaning the enclosure, inspecting and tightening connections, checking and replacing seals, cleaning coolers, and inspecting and cleaning the oil tank.
Connection and Grounding Inspection: Regularly check the transformer’s electrical connections and grounding system to ensure they are secure and reliable. Address any looseness, burn damage, or corrosion promptly.
Circuit Maintenance Plan: Establish a regular circuit maintenance schedule, including transformer patrols, measurements, and repairs, to ensure the safety and reliable operation of electrical equipment.
The above procedures represent general inspection, testing, and maintenance practices for transformers. Specific testing methods and instruments can be selected based on actual conditions. Always strictly follow operational procedures and ensure appropriate safety measures are in place.
