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M E D I U M V O LTA G E P R O D U C T S
5.7. Connect through disconnect
emergency rack out (Fig. 9)
1. In the case of a locking magnet –RL2 fault, in an
emergency the truck can be racked out manually
following the instructions below:
a. Open the circuit breaker
b. Verify Close/Open Indicator shows OPEN
c. cut off the power supply to the auxiliary
circuit
d. verify "READY" indicator lamp turns off and
wait 10 minutes.
e. open the enclosure door
f. remove the circuit breaker front protection
shield
g. using the manual lever, carry out an
emergency racking out operation, keeping
the moving anchor of the locking magnet
–RL2 pressed down by means of a screwdriver
during the initial stage of racking-out (Fig. 9).
Fig. 9
5.8. Installation of withdrawable
circuit breakers
The withdrawable circuit breakers are preset for
use in Vesta switchgear or PowerCube modules.
For racking-in/racking-out of the switchgear:
connect the auxiliary circuits thereby supplying the
locking electromagnet in the truck, fully insert the
crank handle (1) (Fig. 8) in the appropriate seat (2)
(Fig. 8) and work it clockwise for racking-in, and
anti-clockwise for racking-out, until the end-of-run
positions are reached (see par. 5.4. - 5.5- and 5.6.).
Circuit breaker racking- in/-out must be carried out
gradually to avoid shocks which may deform the
mechanical interlocks and the end-of-runs.
The torque normally required to carry out racking-
in and racking-out is <25 Nm.
This value must not be exceeded. If operations are
prevented or difficult, do not force them and check
that the operating sequence is correct.
NOTE
To complete the racking-in/out operation,
about 20 turns of the crank handle are
required .
When the circuit breaker has reached the
connect/ disconnect position it can be
considered as racked into the switchgear
and, at the same time, earthed by means
of the truck wheels.
Withdrawable circuit breakers of the same
version, and therefore with the same
dimensions, are interchangeable.
For the circuit breaker installation
operations, also refer to the technical
documentation of the above-mentioned
switchgear.
CAUTION
The racking-in/out operations must always
be carried out with the circuit breaker open.
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