The testing items for power transformers and reactors are as follows:
(1) Chromatographic analysis of dissolved gases in oil;
(2) The DC resistance of the winding and the bushing (to determine the welding quality of the coil internal joints, lead to coil joints, tap changer to lead, and whether there are open circuits and short circuits in the tapping positions and current carrying parts of the tap changer);
(3) Insulation resistance and absorption ratio (measuring insulation resistance is to detect concentrated defects in electrical equipment, overall moisture or moisture with continuity;
(4) The tg of the winding;
(5) Insulation resistance of iron core;
(6) The insulation resistance of the clamp;
(7) Winding leakage current;
(8) The voltage ratio of all tap connections in the winding , which need to check all parameters fully comply with design value): and outgoing cables to the switch in a correct connection etc;
(9) Testing and inspection of on-load voltage regulating devices;
(6) The insulation resistance of the clamp;
(10) Temperature measurement device and secondary circuit test;
(11) Electrical relays and their secondary circuit tests;
(12) Calibration of pressure release device;
(13) Cooling device and its secondary circuit inspection test.
Test content of SF6 circuit breaker
(1) Measure the insulation resistance of the insulation rod;
(2) SF6 gas leakage test;
(3) Insulation resistance of auxiliary circuit and control circuit;
(4) Closing resistance value and input time of closing resistance;
(5) Conductive circuit anode;
(6) DC resistance of opening and closing coils;
(7) The operating mechanism is very sensitive to the operating voltage of the contactor, whether it is on and off the electromagnets.
Test content of vacuum circuit breaker:
(1) Insulation resistance;
(2) Conductive circuit anode;
(3) The minimum operating voltage of the closing contactor and the opening and closing electromagnet of the operating mechanism;
(4) Insulation resistance of the closing contactor and the opening and closing solenoid coil, as well as AC voltage withstand test of the DC positive auxiliary circuit and control circuit;
(5) The closing and opening time of the circuit breaker, the synchronization of opening and closing, and the contact;
(6) The bouncing process during opening and closing.
High voltage switchgear
(1) Insulation resistance of auxiliary and control circuits;
(2) Live display;
(3) The conductive circuit resistance of circuit breakers, isolation switches, and isolation plugs;
Isolation switch
(1) The insulation resistance of organic materials supporting insulators and insulation rods;
(2) The operation status of the operating mechanism;
(3) Insulation resistance of the secondary circuit;
Voltage transformer
(1) Insulation resistance;
(2) Dielectric loss tg;
Current transformer
(1) Insulation resistance of winding and end screen;
(2) Dielectric loss tg;
(3) Capacitance;
Lightning arrester
(1) DC 1mA voltage and leakage current at 0.75U (check the insulation status of the zinc oxide lightning arrester at the end of breakdown;
(2) AC leakage current at operating voltage;
(3) Insulation resistance;
(4) The operation of the discharge counter.
Capacitor
(1) Pole to shell insulation resistance (check the insulation of the casing. The capacitor needs to test the insulation resistance values of two pole plates to ground);
(2) Capacitance value;
(3) Measurement of parallel resistance value;
(4) Check for protruding belly and oil leakage;
Series reactor
(1) Insulation resistance and DC resistance reactance values of windings
Reactance coil
(1) Insulation resistance
(2) DC resistance of primary winding
Bushing
(1) Main insulation and capacitive bushing end screen insulation resistance to ground
(2) Main insulation and capacitive bushing to ground terminal screen tg and capacitance
Grounding device
(1) Lightning protection strips for towers and buildings
(2) Grounding resistance of independent Lightning rod
(3) Check the conduction resistance between the grounding downlead of power equipment and the grounding grid of the effective Earthing system
(4) Connection condition and connection resistance test
(5) Grounding grid continuity test
Secondary circuit
(1) Insulation resistance test
(2) AC withstand voltage
Verification of protective device protection action
(1) 220kV/110kV line protection
(2) Main transformer power protection
(3) Main transformer non electric quantity protection
(4) Line protection
(5) Joint protection
(6) 35kV line protection measurement and control
(7) 35kV capacitor, reactor, SVG measurement protection
(8) Verification of fault recorder.
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