First of all, we should know that in the procedure, the transformer handover test items include the following 15 items:
1. Insulation oil test or SF6 gas test
2. Measure the DC resistance of winding and bushing
3. Check the voltage ratio of all taps
4. Check the three-phase wiring group of the transformer and the polarity of the outgoing line of the single-phase transformer
5. Measure the insulation resistance of iron core and clamp
6. Test of non-pure porcelain bushing
7. Inspection and test of on-load voltage regulating and switching device
8. Measure the insulation resistance, absorption ratio or planned index of winding and bushing
9. Measure the dielectric loss factor and capacitance of winding and bushing
10. Transformer winding deformation test
11. AC withstand voltage test of winding and bushing
12. Long-term induced voltage withstand test of winding and bushing with partial discharge measurement
13. Impulse closing test under rated voltage
14. Check the phase
15. Measurement noise
Test items of various transformers shall meet the following requirements:
1. Oil-immersed power transformers with a capacity of 1600kVA and below can be tested according to paragraphs 1/2/3/4/5/6/7/8/11/13 and 14.
2. Dry-type transformer can be tested according to 2/3/4/5/7/8/11/13 and 14.
3. The converter and rectifier transformer can be tested according to paragraphs 1/2/3/4/5/6/7/8/11/13 and 14.
4. The current transformer can be tested according to paragraphs 1/2/3/4/5/6/7/8/11/13 and 14.
5. Earthing transformer and zigzag transformer can be tested according to paragraphs 2/3/4/5/8/11 and 13, and oil-immersed transformer shall be tested according to paragraphs 1 and 9.
6. The through-type current transformer and capacitive bushing shall be tested according to the test items of the transformer and bushing respectively;
7. The ordering party shall witness all delivery test items for the transformer transported separately and assembled on site, and the site test shall be carried out according to this standard;
8. Accessories such as gas relay, oil flow relay, pressure relief valve and gas density relay shall be inspected.