Operating Rules for Power Transmission and Power Failure of High Voltage Switchgear

KYN28A-12 high voltage switchgear “five prevention” interlock operation requirements;

1. Prevent the error of the circuit breaker – circuit breaker hand must be in the working position or test position, circuit breaker can be closed, open operation.

2. Prevent moving circuit breaker handcart with load – Circuit breaker handcart can only be pulled out or pushed into the working position when the circuit breaker is in the open state.

3. Prevent charged grounding knife – circuit breaker hand car must be in the test position, grounding knife can be closed operation.

4. Prevent power transmission with grounding knife – grounding knife must be in the opening position, circuit breaker handcart can be pushed into the working position for closing operation.

5. To prevent entering the electric interval – circuit breaker hand must be in the test position, grounding knife in the closing state, to open the back door;Switch cabinet without grounding knife must be after high voltage outage (open the rear door magnetic lock), to open the back door.

Note: KyN28A-12 high voltage switchgear should be operated with closed door during normal operation.

One. Power transmission operation procedure:

1. Through the transfer car circuit breaker handcart (or PT handcart) pushed to the front of the cabinet, the transfer car to the appropriate position, the front positioning keyhole plate of the transfer car is inserted into the baffle socket in the cabinet body and the transfer car is locked with the cabinet body;When the hand cart into the cabinet, pull the left and right handlebars of the hand cart inward to the handle ⅱ position and push the hand cart smoothly into the test position of the switch cabinet, and then push the left and right handlebars outward to the handle ⅰ position at the same time, so that the hand cart propulsion mechanism and the switch cabinet can be reliably locked.When it is confirmed that the handcar and the cabinet are locked, release the lock of the transfer car and the cabinet, and push the transfer car.

2. Insert the secondary plug of the hand car into the secondary socket of the switch cabinet and lock it with the fastener;

3. Close the back door (cable room door) and front door (circuit breaker room door) of the switch cabinet;Open the ground knife operation valve, use the ground knife operation handle (turn 90° counterclockwise) to open the ground knife, draw out the ground knife operation handle to close the ground knife operation valve, and confirm that the ground knife is in the open state.

4. Check that the control, closing, signal, AC and bus voltage and other power switches (or secondary fuses) in the instrument room are in the closing state, and observe that the power voltage is within the normal range, then close the instrument room door.

5. Use local or remote operation mode to control the circuit breaker (in the test position of the switch cabinet) to close and divide once each, and confirm the circuit breaker control loop wiring and signal loop display is correct.

6. Insert the handcart push rocker into the operation hole on the panel of the handcart, turn clockwise to push the handcart into the working position of the switchgear (when the handcart reaches the working position, it will make a “clicking” sound), and take out the handcart push rocker.

7. Use local or remote operation mode to control the operation (in the switch cabinet working position) circuit breaker closing.

8. Check the switch cabinet live display A/B/C three-phase indicator light on, at this time the switch cabinet has been in high voltage live state, measure or observe the microcomputer protection device display bus voltage and outgoing current is in the normal range.

Two. Operation procedures for power failure:

1. Use local or remote operation mode to control the operation (in the switch cabinet working position) circuit breaker opening.

2. Check that the A/B/C three-phase indicator on the power-on display of the switch cabinet is off.At this time, the switch cabinet has been powered off at the high voltage outlet side, but the high voltage bus side is still in the live state (hot standby state).

3. Use the handcart to push the rocker (counterclockwise) to exit the handcart to the test position of the switch cabinet (when the handcart reaches the test position, there will be a “clicking” sound), and take out the handcart to push the rocker.

At this time, the circuit breaker is in the test position of the switch cabinet and belongs to the state of waiting for power failure (cold standby state).The first, second and third steps of the transmission operation procedure can be omitted when the power is transferred again.

Three, hand out of the cabinet out of the operation procedures:

1. When the circuit breaker handcart (or PT handcart) needs to be pulled out of the cabinet, all steps of the blackout operation procedure should be completed first.

2. When the grounding tool needs to be closed, the valve of the grounding tool should be opened first, and the handle of the grounding tool should be turned 90° clockwise to close the grounding tool. Then, pull out the handle of the grounding tool and confirm that the grounding tool is in the closing state.(If the grounding knife closing operation is not required, this operation is not required)

3. Open the front door of the switch cabinet (circuit breaker room door), remove the secondary plug of the handcart and lock the plug buckle on the handcart frame.

4. Place and lock the transfer truck in the designated position in front of the switch cabinet (same as when loading the hand truck);Pull the left and right handlebars of the handcart inward to the handle ⅱ position at the same time, and pull the handcart out to the transfer car, push the left and right handlebars outward to the handle ⅰ position at the same time and lock the lock hole of the transfer car reliably.

5. Check that the upper and lower static contact protective valves in the switch cabinet are in the automatic closing position, and close the front door of the switch cabinet (circuit breaker room door).

6. If the handcar is to be transported over a long distance by a transfer vehicle, extra care should be taken in the process of pushing the transfer vehicle to avoid accidents.

Four. Operation procedures for maintenance of power failure in high voltage cable room:

1. Complete all steps of the blackout operation procedure.

2. Open the ground knife operation valve, use the ground knife operation handle (clockwise 90°) to close the ground knife, pull out the ground knife operation handle, and confirm that the ground knife is in the closing state.The outgoing side of the cable is safely grounded.

3. Open the back door of the switch cabinet (cable room door), and check and confirm that all conductive parts of the cable room are completely in the state of power failure with the high-voltage electric inspection device. Then the maintenance personnel can enter the high-voltage cable room for work.

Five. Operation procedures for power failure maintenance of high voltage bus room:

1. Complete all steps of the blackout operation procedure.

2. Confirm that the circuit breaker hand truck of the incoming cable cabinet and female union cabinet is in the test position or isolated position outside the cabinet, and confirm that the incoming cable or bus is in the complete power failure state.

3. Open the rear cover or top plate of the high voltage bus room, check and confirm that all conductive parts of the bus room are completely in the state of no voltage with the high voltage electric test device, and install the ground cable before the maintenance personnel can enter the high voltage bus room for work.

Notes:

1. After each step of the operation procedure is completed, it must be confirmed that the switch cabinet and hand truck parts are in normal state before the next step of the procedure operation.In the operation process of the above procedures, if any obstacles are encountered, do not forcibly operate, should first check whether the operation procedures are correct, and check and eliminate other faults, can continue to operate.

2. Switch cabinet power transmission sequence: incoming cable cabinet – PT cabinet – Outgoing cable cabinet;Power failure sequence of switch cabinets: Outlet cabinet – PT cabinet – Incoming cabinet.

3. When the PT handcar is used to enter or exit the cabinet, the operation steps of the grounding knife can be omitted.

4. The manual closing, opening button and manual energy storage device of the circuit breaker handcar are only used during debugging or maintenance.

5. In the process of power-on operation, the equipment should be inspected and recorded at any time. If any abnormal phenomenon is found (such as abnormal heating or abnormal sound of components, etc.), the power should be cut off and repaired in time.