ABB Vmax 12, Installation And Service Instructions Manual

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12 12 VMAX - INSTALLATION AND SERVICE INSTRUCTIONS
5.4. Withdrawable circuit breaker
The withdrawable circuit breakers (see fig. 5) are
available for UniGear type ZS1 switchgear, PowerCube
modules and UniSec switchgear.
They consist of a truck on which the supporting
structure of the circuit breaker is fixed.
The cord with the connector (14) (plug) for
connection of the operating mechanism electrical
accessories comes out of the connection (15).
The strikers for operating the contacts (racked-in/
isolated) placed in the switchgear are fixed in the top
part of the circuit breaker.
The slides (9) for operating the segregation shutters
of the medium voltage contacts of the enclosure or
of the switchgear are fixed on the sides of the circuit
breaker.
On the front part of the circuit breaker truck, the
crosspiece is mounted with the handles (17) for
hooking up the circuit breaker for the racking-in/out
operations by means of the special operating lever
(16). The circuit breaker is completed with the
isolating contacts (8).
The withdrawable circuit breaker is fitted with special
locks on the front crosspiece, which allow hooking up
into the corresponding couplings of the switchgear.
The locks can only be activated by the handles with
the truck fully resting against the crosspiece. The
operating lever (16) must be fully inserted (also see
par. 7.6.). A lock prevents the truck from advancing
into the enclosure or fixed part when the earthing
switch is closed. Another lock prevents racking-in and
racking-out with the circuit breaker closed. With the
truck in an intermediate position between isolated
and racked-in, a further lock prevents circuit breaker
closing (either mechanical or electrical).
A locking magnet is also mounted on the truck which,
when de-energised, prevents the truck racking-in
operation.
On request, an interlock is also available which
prevents circuit breaker racking-in with the door
open, and door opening with the circuit breaker
closed.
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5. Description