Closing Mechanisms Clause Samples
Closing Mechanisms. 5.7.1 The closing mechanism shall be either of the hand charged, spring or hand operated, spring assisted or motor wound spring charging or solenoid operated types as specified in the Detail Technical Specification.
5.7.2 The closing action of the hand operated, spring assisted mechanisms shall ensure that once closing is initiated the action becomes independent of the operator.
5.7.3 Motor wound spring charging mechanisms shall be provided with hand cranks for emergency use should the electrical closing circuitry become inoperative.
5.7.4 Slow closing facilities shall be provided on all mechanism types for maintenance purposes and these facilities shall only be accessible with the circuit breaker in the "withdrawn" position.
5.7.5 All mechanisms shall be of the trip-free type and it shall not be possible for the mechanism to maintain the circuit breaker in a "closed" position during fault conditions or when the "open" signal has been initiated.
5.7.6 The electrical closing circuitry shall be open circuited as soon as the closing sequence has been completed to prevent continued electrical loading of the closing circuitry and to deactivate the closing signal until a new sequence is initiated.
5.7.7 Where auto-reclosing duties are specified, the mechanisms shall be capable of performing a "BREAK‑MAKE‑BREAK" operation.
5.7.8 All electrically operated closing devices shall be at least suitable for operation at any voltage between 80 % - 120 % of the nominal control voltage at the device terminal. The nominal control voltages are specified in the Detail Technical Specification.
5.7.9 Anti-pumping devices shall be provided on all mechanisms to prevent pumping while the closing circuit remains energized and the circuit breaker either fails to latch or trip during closing due to the operation of the protection system. The arrangement shall be to the approval of the Department.