Zhejiang Zhi Duoxin Electric Co., Ltd.

1. Prevent the circuit breaker from being divided and closed by mistake

For manned substations, this can be achieved with different numbers of red and green triggers (red and green triggers on transfer switches are not generally used now). That is, each circuit breaker corresponds to a uniquely numbered red and green trigger, usually placed on the control screen. unattended

Because the switching-off of circuit breaker is remote operation, the red and green trigger mode cannot be applied in Chinese substation, and can only be electric interlocking. The door of the instrument room of the high voltage switchgear is generally equipped with a break switch (KK switch), and the instrument room is equipped with a program lock. When the cabinet is in normal operation, remove the program lock key,

Close the door of the instrument room to prevent the circuit breaker from misopening and closing, but now generally installed on the cabinet with a key switch (KK switch). Instrument door. When the switchgear is in normal operation, remove the key to prevent the circuit breaker from accidentally opening and closing.

2. Prevent on-load split and close up and down disconnecting switch or on-load push-pull circuit breaker trolley.

Enforce interlocking using mechanical interlocking. This requirement is due to the inability to disconnect the normal load current between the disconnector and the mobile and static contacts of the handcar. In case of misoperation, it will burn the disconnector and the static and static contact of the hand car, and the accident may be further expanded. The KN28-12 switchgear is breaking

The circuit breaker is locked at the working position or test position by the mechanical interlock of the circuit breaker handcart (by interlocking the connecting plate with the interlocking plate of the chassis car, so that the circuit breaker presses the lead screw circuit breaker of the chassis car when the circuit breaker is closed). When the circuit breaker handcart is not in the working position or test position (lift the connecting plate and use the shaft

The plastic clamps on it to prevent it from closing), the breaker handcar cannot close

3, prevent grounding switch live operation or temporary grounding wire hook.

This function requires mechanical interlocking because it is associated with human short-circuit grounding. When the circuit breaker is in the working position and the cable chamber is energized, the baffle (6mm thick) at the position of the handcart cannot extend the interlock with the chassis, and the interlock of the ground switch cannot be pressed down. The shaft hole of the ground switch operation is blocked, and the shaft of the ground switch operation is not available

To prevent the grounding switch from energizing. At the same time, in Nanjing area (or have special requirements), but also added a locking electromagnetic lock or locking electromagnet. When the circuit breaker is in the working position and charged, the magnetic lock rod is extended to block the ground switch interlocking plate so that it cannot be pressed down to ensure that it cannot

Closing.

4. Prevent power transmission when the temporary ground cable is connected or the ground switch is closed.

When the KN28-12 switchgear ground switch is closed, the handcart position baffle is interlocked with the chassis, so that the circuit breaker handcart cannot be moved to the working position, so that the switch cannot be closed and transferred. This function requires mechanical interlocking and is also designed to prevent artificial short-circuit grounding. When the ground switch of the switchgear is connected with

When the chassis is connected, the handcart position baffle is interlocked with the chassis car, but the breaker handcart cannot be moved to the working position so that the switch cannot be closed for power transmission.

5. Prevent people from entering the charged interval by mistake

Mechanical interlocking is also commonly used to prevent the operator from being electrocuted. The instrument room, bus room, handcart room and cable room of the high voltage switchgear are separated from each other. When the handcart is opened, the trap door (insulation board or aluminum plate) automatically closes, the secondary static contact is completely isolated, and the switchgear instrument room is equipped with live display.

KYN28 cabinet is not charged when the back door down the ground switch] equipped with electromagnetic lock. ] Can't open, use ground switch to solve. When powered, use the back door at the back of the ground switch shaft. The interlocking part is interlocked with the rear lower door and cannot be opened later. In addition, when the handcart is in the working position, the secondary plug cannot be pulled out when locked.