Daily Maintenance Of Sf6 Circuit Breakers

Daily inspection and maintenance summary Strengthen the inspection of electrical anti-jump circuits. The judgment method is as follows:
(1) When sf6 circuit breaker operating mechanism is closed, use the voltage range of the multimeter to check whether the auxiliary switch can connect the anti-jump relay;
(2) When the closing signal cannot be removed, check whether the anti-jump relay can keep the closing circuit in the interrupted state. Its contacts keep the anti-jump circuit conductive. Even if the auxiliary switch is switched after sf6 circuit breaker spring mechanism is opened, the closing circuit will not be conductive;
(3) After the closing signal is removed, check whether the anti-jump relay is reset.
2. SF6 circuit breaker low pressure lockout
For equipment in operation, when the SF6 gas drops to the lockout pressure (0.61MPa for this circuit breaker), the density
relay contact (normally closed point) returns to closed, driving the lockout relay in the cabinet to operate electrically, and the normally closed contacts of the lockout relay connected in series
to the control circuit are disconnected at the same time, thereby locking the entire closing (opening) circuit and making the circuit breaker unable to close (open).
Figure (IV)
Two sets of locking relays K03 and K13 are set in the SF6 electrical circuit and connected in series in the opening and closing circuit
to ensure the reliability of the action. P2 is the normally closed contact of the density relay, which will close when the pressure is lower than the set value
to drive the locking relays (K03, K13) and lock the opening and closing circuit.