1. According to the engineering drawings, the wiring is proper, the line number identification on both sides should be clear, and the identification range should meet the requirements.

　　 2. The current and working voltage power supply circuit should be grounded at the entrance and exit of the secondary side of the transformer. The working voltage power supply circuit should be maintained with a circuit breaker.

　　 3. The secondary circuit line of the control panel cabinet should have no radio frequency connector, and there should be no radio frequency connector in the middle of the frequency conversion cable or line. If there is a radio frequency connector, it should be linked according to its long terminal block.

　　4. The secondary circuit of the split-combination voltage transformer has an excellent insulation layer, and the working voltage control circuit and the current flow control circuit should not be mixed.

　　5. The wiring of the secondary circuit should be arranged neatly and elegantly, and the connecting screws between the wiring and the electrical components and the terminal should not be loose. The spacing between the wiring binding points should meet the requirements.

　　 6. The cycle time cannot be reversed, and the zero line fire line and phase angle should conform to the design plan and requirements. For the wiring of the transformer with differential protection, the phasor diagram of both arms must be accurately measured before the capital is invested to check the accuracy of the wiring.

　　 7. The secondary circuit cable or cable should be copper core wire. The cross section of the transformer control loop shall not be less than 1.5 mm. The entrance and exit terminal should use unique current terminal. The secondary winding that is not applied to the transformer should be short-circuited and installed on the power strip.