5 Operation
The filling flange W1 for filling the circuit-breaker with SF
6
gas is located inside the drive mechanism housing
(connecting thread M26x1.5 or M45x2). The operational gas pressure can be read on the pressure gauge MA
(see section 3.8
Control).
WARNING
Release the SF
6
-pressure before working on the screw connections of the gas chamber.
If the above signal is initiated again after some time, the leak must be located and, if possible, sealed. If the leak
cannot be sealed, the nearest Siemens representative should be notified.
5.1.3 General
Lockout
If the SF
6
pressure in the circuit-breaker drops so low that perfect arc-quenching can no longer be ensured, a
general lockout becomes effective and blocks all further operation.
5.1.4
Mechanical Reclosing Lockout
If the circuit-breaker pole is in the CLOSED position, a mechanical reclosing lock-out in the operating mechanism
comes into effect. It prevents the operating mechanism from being switched back on.
5.1.5
Max. Permissible Number of Interruptions
The relationship between breaking current I, max. permissible number of interruptions is shown in Fig. 57. If the
interruptions take place with higher current, the number of possible interruptions decreases as shown in Fig. 57.
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