Withdrawable Circuit Breakers - ABB VD4 Installation And Service Instructions Manual

V D 4 - INSTALLATION AND SERVICE INSTRUCTIONS
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4. Description

4.8 Withdrawable circuit breakers

The 63 kV circuit breakers are available for ZS1
switchgear (see fig. 6).
They consist of a truck on which the supporting
structure of the circuit breaker is fixed.
Circuit breakers for UniGear ZS1 (fig. 6)
The cord with the connector (plug) for connection of
the operating mechanism electrical accessories
comes out of the connection (15).
The strikers for operating the contacts (connected/
isolated) placed in the switchgear are fixed in the
top part of the circuit breaker.
The shutter actuator (9) and roller (18) are provided
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.
The crosspiece with the handles (17) for hooking up
the circuit breaker for the racking-in/out operations
by means of the special operating lever (16) is
mounted on the front part of the circuit breaker
truck.
The circuit breaker is completed with the isolating
contacts (8).
16
14
11
Caption
1 Lever for manually charging the closing spring
2 Signalling device for circuit breaker open/closed
3 Rating plate
4 Opening pushbutton
5 Closing pushbutton
6 Signalling device for closing spring charged/discharged
7 Operation counter
8 Isolating contacts
9 Slide for operating the switchgear shutters (UniGear ZS1, PowerCube,
ZS8.4)
Fig. 6
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. 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
connected, 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 available which prevents
racking-in of the circuit breaker with the door open,
and door opening with the circuit breaker closed.
The lever for loading the closing spring (1) in the
manual mode is built into the operating mechanism.
The spring is loaded by repeatedly lowering the lever
with linear movements until the yellow indicator (6)
appears to show that loading is complete.
The spring can only be loaded with the switchgear
door open.
8
5
4
6
2
9
10
10 Truck
11 Locks for hooking into the fixed part
12 Mechanical override of the undervoltage release (on request)
13 Cabling connection
14 Operating lever for circuit breaker racking-in/out
15 Handles for activating the locks (11)
16 Shutters actuator (for UniSec version only)
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3
1
7
15