High voltage switchgear operation five anti interlocking function
Jan 07, 2022
Five defenses, usually refers to the "five defenses" of the high voltage switchgear or the "five defenses" of the power distribution room.
1, prevent with load separation, close isolation switch. (Circuit breaker, load switch, contactor closed state cannot operate the disconnecting switch.)
2, prevent the fault, fault circuit breaker, load switch, contactor. (Only the operation command corresponds to the operating device can operate the operated device)
3. Prevent the circuit breaker and load switch from being closed when the grounding switch is in the closed position. (Only when the grounding switch is in the opening state, the isolation switch can be closed or the handcart can enter the working position, and the circuit breaker can be operated and the load switch can be closed)
4, to prevent the wrong grounding switch when live. (Only when the circuit breaker is on, the disconnecting switch can be operated or the handcart can be retreated from the working position to the test position, and the grounding switch can be closed)
5. Avoid straying into live interval. (Open the door and enter the compartment only when the compartment is not electrified)
Power distribution room of the "five" namely fire, waterproof, lightning, snow, small animals. One "is to maintain good ventilation.
The realization of "five protection" functions has become one of the important measures of electric power safety production. With the continuous development of power grid, the technology is constantly updated, and the error prevention device is constantly improved and perfected.
The design principle of error prevention device is: all high voltage electrical equipment which may cause misoperation should be equipped with error prevention device and corresponding error prevention electric locking circuit.
Conventional anti-error locking device Conventional anti-error locking device mainly has 4 kinds: mechanical locking, program locking, electrical interlocking and electromagnetic locking.
1 mechanical locking
It is in the switch cabinet or outdoor knife operating parts with mutual restriction and linkage of the mechanical mechanism to achieve the sequence of action of the closed iron requirements. Mechanical locking in the process of operation without the use of keys and other auxiliary operations, can be realized with the correct operation sequence, automatic step by step unlock. In case of misoperation, automatic locking can be realized to prevent misoperation. Mechanical locking can achieve forward and reverse locking requirements, with locking intuitive, not easy to damage, maintenance workload is small, easy to operate and other advantages.
2 Program lock (or mechanical program lock)
It is to use the key along with the operation program transfer or replacement to achieve the requirements of unlocking operation. Its biggest advantage is that key transfer is not limited by distance, so its application range is wide. The program lock has the auxiliary action of key transfer and key number change in the operation process, which is in line with the operation order of the limited unlocking conditions in the operation ticket, and the walking route specified in the operation ticket is completely consistent, so it is easy to be accepted by the operator.
3 Electrical close money
It realizes unlocking operation through the action of the electromagnetic mechanism of the electromagnetic coil, and is an indispensable locking element in the locking link to prevent straying into the charged interval. The advantage of electric latching is that it is easy to operate and there is no auxiliary action.
