Vacuum degree check apparatus for vacuum circuit breaker and method for checking its degree of vacuum

摘要

PROBLEM TO BE SOLVED: To solve the problem that, when maintaining a vacuum circuit-breaker, it is necessary to pull out the vacuum circuit-breaker or remove a power cable or an overhead transmission line and a maintenance time may be prolonged.SOLUTION: A vacuum degree confirmation device comprises: a sealed container; a vacuum valve that includes a movable contact and a fixed contact and opened/closed by a contact opening/closing operation mechanism; and a bellows-like body that a movable contact shaft of the movable contact penetrates air-tightly. An insulation rod linked to the movable contact shaft, an operation shaft linked to the movable contact shaft for opening/closing drive of the fixed and movable contacts with the contact opening/closing operation mechanism and an opening spring energizing the fixed and movable contacts in a separate direction are disposed while being linked, respectively. On the operation shaft, a load measuring device for measuring a load of the operation shaft is provided in a freely attachable/detachable manner. When the vacuum circuit-breaker is completely produced, an initial measurement of the load is recorded and stored by the load measuring device. When maintaining the vacuum circuit-breaker, the initial measurement is compared and collated with a measurement during the maintenance, thereby detecting and confirming a vacuum degree of the vacuum valve during the maintenance.