Description
30
9229 9947 176 0C
2013-03-28
Priority opening
To lock vacuum circuit-breakers, switchgear trucks, withdrawable sections or
disconnectors in OPEN position, the drive mechanisms of the vacuum circuit-
breaker can be equipped with "priority opening".
Fig. 39
Priority opening
The assembly "priority opening" has three positions. These positions are actuated
by an interrogation or actuation component in the system.
Trip-free position
Actuating "priority opening" with the system's actuation in the first position (trip-free
position, b) triggers opening and prevents closing as long as priority opening is
actuated.
Spring-dump position
In the second position (spring-dump position, c) the vacuum circuit-breaker remains
in open state and is reliably secured against reclosing.
In addition, when actuating the interlocking device in the second position, the closing
spring is relaxed by a no-load switching operation.
The closing and the opening spring are now relaxed and hence all energy storages
of the vacuum circuit-breaker discharged.
The operating position (CLOSED/OPEN) of the vacuum circuit-breaker is not
interrogated with "priority opening".
a)
b)
c)
a)
Idle position
b)
Trip-free position
c)
Spring-dump position
*)
Interrogation or actuation component (max. actuation force 70 N)
Note
Compared to the mechanical interlock (see Fig. 29), actuation of the system's
interrogation and actuation component is not prevented if the vacuum circuit-
breaker is closed.