Step 1
When the isolation switch is operated, check that the circuit breaker and the ground switch of the corresponding loop have been opened and opened in place, and confirm that the ground cable in the power supply range has been removed.
Step 2
When operating the isolation switch of the motor mechanism (including the ground switch), the motor power supply small switch of the isolation switch operating mechanism should be closed first, and the motor power supply small switch of the isolation switch operating mechanism should be disconnected immediately after the operation is complete.
Step 3
To operate the isolation switch in a power outage, pull the load side isolation switch first and pull the power side isolation switch later. When the isolating switch is powered on, the isolating switch on the power side should be closed first, and then the isolating switch on the load side.
Step 4
The isolation switch of electric operation should generally be operated on the background machine, when the remote control fails, it can be operated on the local measurement and control unit (protection chamber) or on the spot, but it must meet the "five prevention" lock conditions, and take the corresponding technical measures, and obtain the permission of the relevant departments at the higher level. 220kV isolation switch can be operated on the spot, but must strictly verify the electrical lock conditions and take the corresponding technical measures; 500kV isolation switch shall not be manually operated in the live state on the site. If manual operation is required, it must be approved by the dispatcher and the chief engineer of the unit, and station leaders or technicians are on the site.
Step 5
When the isolation switch is operated (including the ground switch), the operator should check whether the actual position of the opening and closing are in place, the contact insertion depth is appropriate and the contact is good, to ensure that the isolation switch operates normally and the position is correct.
Step 6
The isolation switch, ground switch and circuit breaker are installed and provided with a blocking device to prevent misoperation. When the switching operation is performed, it must be carried out in strict accordance with the operation sequence. If the blocking device fails or the isolation switch cannot operate normally, the position status of the circuit breaker, isolation switch and ground switch must be checked one by one according to the conditions required for blocking. After the conditions are met and the approval procedures are completed, the blocking can be lifted for operation.
Step 7
When the electric isolation switch is operated manually, the power supply should be disconnected, the special handle should be inserted into the rotating shaft, and the counterclockwise shaking is the closing of the switch, and the clockwise shaking is the opening of the switch. 500kV isolation switch shall not be operated manually with power on. After all the isolation switches and ground switches are manually operated, the door should be closed to prevent the electric operation from being locked.
Step 8
The mode selection handle in the 500kV isolation switch mechanism box must be in the "three-phase" position when normal.
Step 9
For an isolating switch equipped with a grounding switch, the grounding switch must be turned on only after the isolating switch is fully opened; On the contrary, when the grounding switch is completely opened, the closing operation of the isolation switch can be carried out, and the operation must be in place.
Step 10
Use the insulation rod to pull the isolation switch or pull the isolation switch through the transmission mechanism, should wear insulation gloves. When operating outdoor high-pressure equipment in rainy days, the insulation rod should have a rain cover and insulation shoes should be worn.
Step 11
Manually closing the isolation switch must be done quickly and decisively. When the isolation switch is about to close in place, do not exert too much force to avoid damage to the support insulator. When it is found that there is an arc or misoperation, the isolation switch is not allowed to open again, so as not to pull the isolation switch with load due to misoperation and expand the accident. Manually pull the isolation switch slowly and carefully. If the arc occurs when the contact is just separated, it should be quickly closed and stop the operation, and immediately check whether the arc is caused by misoperation.
Step 12
When the isolation switch of the phase division operating mechanism loses the operating power supply or the electric failure needs to be manually operated, in addition to fulfilling the necessary procedures according to the unlocking regulations, the A and C phases should be closed first during the closing operation, and the B phase should be opened first during the opening operation, and then the other two phases should be opened.
