Operating Mechanism Clause Samples
Operating Mechanism. 7.2.1 The operating mechanism shall be spring-only type for 27.6 ,69kV, and 138kV breakers rated 40kA and 63kA. The operating mechanism may be hydraulic or spring type, or a combination of these, for 69kV and 138kV circuit breakers rated 50kA and above.
7.2.2 The operating mechanism for SF6 breakers shall be electrically trip-free and, in addition, mechanically trip- free, non-pumping and of the stored energy type providing a minimum of an initial open - close - open operation followed by the capability of performing a close - open operation every fifteen seconds, maximum, without de-rating.
7.2.3 Any spring-type operating system motors shall be the universal (AC/DC) type, 125V. An automatic transfer switch shall be provided for the universal motor. The 120 VAC feed will be the primary feed and the 125 VDC will be the alternate feed from the transfer switch. In the event of a loss of A/C station service, power to replenish the stored energy in the spring operator for subsequent open-close operations will be fed from the station battery.
7.2.4 Mechanism equipment, including piping and linkages, shall be factory installed as completely as possible.
Operating Mechanism. The breaker operating mechanism shall be spring type and be provided with an operations counter.
3.11.1. The breaker operating mechanism shall be electrically trip-free with an anti-pumping feature.
3.11.2. The operating mechanism shall be capable of storing one “OPEN – CLOSE – OPEN” operations sequence without the need for external power or spring charging.
3.11.3. The operating mechanism shall be designed to initiate an alarm locally and/or remote location for both AC and DC potentials, in the event of power loss to the operating mechanism and heating elements.
Operating Mechanism. 6.5.1 The switch shall have three positions, namely "ON", "OFF" and "EARTH".
6.5.2 Except for removing the earth, the switch actuating mechanism shall have a positive action and shall be spring assisted to ensure that once the operation is initiated it becomes completely independent of the operator.
6.5.3 The fused oil switch shall close fully when making onto a fault to ensure full clearance of the fault by the fuses before tripping and opening the switches.
6.5.4 A blown fuse on any of the three phases shall open all three phases of the switch and shall inhibit the closure of the switch pending fuse replacement.