In what order must the power outage operation be carried out

The power safety work regulations (substation part) of the home grid company stipulate that the operation of power failure should be in accordance with the circuit breaker (switch) and the load side isolation switch.

Knife switch) - the order of the power side isolation switch (knife switch) is carried out in turn.

The interpretation of this provision is: the purpose of pulling the load side isolation switch first is to pull the load side isolation switch first if the circuit breaker is not actually disconnected, so that the fault point caused by the load brake is on the load side of the circuit breaker, so that the fault can be cut off by the circuit breaker protection action and the impact of the accident is minimized.

On the contrary, pull the bus side isolation switch first, the fault point caused by the arc is in the bus side range, which will lead to bus power failure and expand the scope of the accident, in addition, the maintenance after the load side isolation switch is damaged, and the maintenance impact of the power outage after the bus side isolation switch is damaged.

That is, when the fault occurs, the protection action is fast, the power failure range is small, and the nature of the accident is light, and the bus should generally be regarded as the power supply side, and only when the bus is initially charged, can the load side be done.

However, in actual implementation, for the double-sided power supply line isolation switch, the main transformer medium and low voltage side isolation switch, bus tie isolation switch, etc., under different main wiring, operation mode and related protection configuration, before the operation of the isolation switch, when both sides of the disconnector are the same power supply side, its operation sequence will also change accordingly.

The operation sequence of the power failure brake is as follows: first cut the circuit breaker (switch), then pull the isolation switch (knife switch), first open the load side knife switch, and then open the bus side knife switch. The order of power transmission and closing is reversed.

The power safety work regulations (substation part) of the home grid company stipulate that the operation of power failure should be carried out in the order of circuit breaker (switch), load side isolation switch (knife switch), and power supply side isolation switch (knife switch).

Power rationing: refers to the measures to pull the circuit breaker of the power supply line in the power system and forcibly stop the power supply. Interrupt the power supply of an area or part of a region when the specific power environment cannot meet the full capacity demand**.

It usually occurs in summer. (The specific behavior is to disconnect the power switch in a certain area at the source of the power supply.)

It can only be closed when power is needed) before it can be used on the load side.

However, in actual implementation, for the double-sided power supply line isolation switch, the main transformer medium and low voltage side isolation switch, bus tie isolation switch, etc., under different main wiring, operation mode and related protection configuration, before the operation of the isolation switch, when both sides of the disconnector are the same power supply side, its operation sequence will also change accordingly.

Electric switch effect. 1) After opening, establish a reliable insulation gap to separate the equipment or lines that need to be overhauled from the power supply with an obvious disconnection point to ensure the safety of maintenance personnel and equipment.

2) According to the needs of operation, change the line.

3) It can be used for small currents in the distribution and closing lines, such as the charging current of bushings, busbars, connectors, and short cables, the capacitance current of switching equalizing capacitors, the circulation current when the double bus is replaced, and the excitation current of the voltage transformer.

4) According to the specific situation of different structure types, it can be used to divide and combine the no-load excitation current of a certain capacity transformer.

The operation sequence of power failure and reverse switch is to first pull the switch, then open the line side knife switch, and finally open the bus side knife switch.

The operation sequence of the reverse switch in the event of a power failure is: first pull the switch, then open the line side knife switch, and finally open the bus side knife switch. The operation sequence of the reverse switch when power transmission is as follows: first close the bus side switch, then close the line side switch, and finally close the switch.

Precautions for power outages:

1. According to the needs of the actual work of the first son on site, all circuit breakers and isolation switches that may send power to the maintenance part should be disconnected. For multi-circuit lines, it is necessary to pay attention to prevent the possibility of sudden calls from other parties.

2. In order to ensure the safety of the operator, when the power is off, the low voltage should be stopped first and then the high voltage, the oil circuit breaker or air circuit breaker should be stopped first, and then the isolation switch should be stopped.

3. There should be an obvious disconnection point after the power failure, and the operating mechanism should be locked for the equipment without an obvious disconnection point. Otherwise, other reliable security measures must be taken.

4. In the event of a partial power failure, the transformer and the instrument transformer should be disconnected from both sides of the high and low voltage to ensure the personal safety of the maintenance personnel. <>

The operation of the power outage must be operated in the order of the vacuum circuit breaker (switch), the load-side isolation switch (knife switch), and the bus-side isolation switch (knife switch). The power transmission closing operation should be carried out in the reverse order of the above.

During power outage maintenance, the "no closing, someone working" sign should be hung.

Power outage operation (or partial power outage operation) must hang a sign (warning) card, if someone is working on the line, the road switch and the knife switch operation handle should be hung "prohibit closing, the line is working!" Warning signs. The hanging and removal of warning signs should be carried out as ordered.

When working on indoor high-voltage equipment, "Stop, high-voltage danger!" should be hung on the fences at the intervals on both sides and opposite sides of the work site and on the aisles where traffic is prohibited. Warning signs.

When working on outdoor ground high-voltage equipment, a fence should be made with ropes around the work site, and an appropriate number of "Stop, High Voltage Danger!" should be hung on the fence. "Warning signs, warning signs must be facing the outside of the fence.

Hang the phrase "Work Here!" at the place of work. Warning signs.

When working on an outdoor frame, the "Stop, High Voltage Danger!" should be hung on the beam adjacent to the live part of the work site. Warning signs.

This warning sign is under the supervision of the staff on duty and is hung by the staff. On the iron frame or ladder used by the staff to get up and down, the phrase "From here up and down!" should be hung. Warning signs.

In the vicinity of other structures that may be climbed by mistake, the words "No climbing, high pressure danger!" should be hung. Warning signs.

It is strictly forbidden for staff to move or remove barriers, grounding wires and warning signs during work.

Should be hung "Do not close!" Someone works. signs.

Safety regulations. Article 84 states: "Circuit breakers (switches) and disconnectors that can transmit electricity to the place of work as soon as they are closed.

Knife brake) should be hung on the operating handle of the hall pat' forbidden to close, someone is working! signs. At the same time, it is specified that the hanging and removal of the signs shall be carried out in accordance with the orders of the dispatcher.

Electrical workers must take the work of hanging the placard seriously. Due to the different types and wiring and different control methods of high-voltage electrical equipment, specific hanging work should be carried out according to the actual situation.