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Revision 04 * INSTALLATION AND OPERATING INSTRUCTIONS 8BT2 * 881-4027.9
please be aware of this coding before the operation.
6.8. Racking the withdrawable device truck
NOTE!
The following instructions for racking the withdrawable device truck apply to:
Circuit breaker
Switch disconnector
Voltage transformer with truck in the metering panel
Control elements of switching device truck
Fig87. Actuating opening and interlock for racking and switching device truck
Racking positions
Withdrawable devices (circuit breaker, disconnector, voltage transformers) are mounted on the
truck. It can be racked to two different positions:
•
SERVICE position
: The contact poles of the switching device are connected with the
busbar and the feeder. The low-voltage connector is plugged in.
•
TEST position
: The contact poles of the switching device are disconnected from the busbar
and the feeder. In this position e.g. electrical interlocks can be checked. The low-voltage
connector can be unplugged.
ATTENTION!
If there is no auxiliary voltage, both the electrical and the mechanical interlocks are
closed. If the interlocks are eliminated, manual switching operations will be possible
despite an existing electrical interlock, and they can cause operational breakdowns.
Ensure that the intended manual switching operation has been released externally.
Racking the withdrawable truck into SERVICE
position
Racking the withdrawable truck into TEST position
Preconditions
•
Truck completely inserted to the TEST position and
interlocked in panel.
•
High voltage compartment door closed.
•
Circuit breaker and Switch Disconnector in OPEN
position.
•
Feeder earthing switch in OPEN position.
•
Low voltage connector plugged in.
•
The truck in SERVICE position
•
Circuit breaker and Switch Disconnector in OPEN
position
•
Feeder earthing switch in OPEN position.
Procedure
To release the truck: Insert the double bit key into
the actuating opening (pos.nr.
in fig87) and
turn 90º clockwise to the “Racking free” position
(manual racking).
To release the device truck: Insert the double-bit
key into the actuating opening (pos.nr.
in fig87)
and turn 90° counter-clockwise to the "Racking free"
position (manual racking).