13
Preliminary operations
• Collect all auxiliary material required for
installation of the cradle retrofit solution
• Clean the insulating bushings on panel side
with clean dry cloths
CAUTION
Use proper personal protective
equipment like hand gloves, helmets
etc. while handling switchgears &
making cable connections.
NOTE
When carrying out installation work, the
regulations in the country of installation must
be strictly complied with.
Disconnect power, then earth and short circuit
connection before proceeding to work on the
switchgear.
Installation of VD4-36kV cradle
retrofit solution in VHA36
switchgear
The installation of VD4-36kV cradle retrofit
solution VCB in existing switchgear type VHA 36
requires modifications in existing switchgear
panel. Refer below steps for installation of
VD4-36kV cradle solution.
1. Remove following components from existing
VHA36 panel (refer fig 14.1, 14.2, 14.3, 14.4)
• SF6 circuit breaker HPA36
• CB compartment door (top) fixed with
shock absorber
• CB compartment main door
• Bottom front door
• Rear sheet of CB compartment
• Racking mechanism assembly
• LHS and RHS guide rails in CB compartment
• 24 pin socket and TEST/SERVICE limit
switches along with wiring from terminal
blocks in panel
• Emergency trip assembly and earth guide
2. Fix/mount following new components in
existing VHA36 panel (refer fig 15.1, 15.2, 15.3)
• Bottom plate assembly after preparing it
along with guide rails, guide brackets and
earth guides
• Rear bottom plate of CB compartment
• Top cover (upper door) assembly above CB
compartment main door
• CB compartment main door suitable for
cradle retrofit solution VCB
• Bottom front door
• 64 pin socket along with wiring up to
terminal blocks in panel
Once the preparation of panel assembly is
completed by mounting new bottom plate with
guide rail & new front door, withdrawable
VD4-36kV cradle retrofit solution VCB can be
inserted in the panel with the help of CB handling
trolley (refer fig 8.2 - Handling with trolley).
Circuit-breaker racking-in/-out must be carried
out properly to avoid shocks which may deform
the mechanical interlocks and the limit switches.
If operations are prevented or difficult, do not
force them and check that the operating
sequence is correct.
CAUTION
During installation of VD4-36kV
cradle solution with withdrawable
VCB, ensure that power supply to the
panel is completely switched off and
there is no residual charge present
on cubicle contact by use of proper
earthing.
Wiring of auxiliary circuit
The auxiliary circuits of the withdrawable
circuit- breaker are fully cabled from the factory
up to male connector.
For the external connections, please refer to the
electric diagram of the enclosure or of the
switchgear. The female connector in the existing
panel must be replaced with the corresponding
female connector suitable for male connector of
CB & cabling of the panel to be done up to the
female connector during installation.
—
Installation
Содержание VD4 Series
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