ABB VD4 Installation And Service Instructions Manual page 22

V D 4 - INSTALLATION AND SERVICE INSTRUCTIONS
22
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5. Installation
T1
Bare copper
• Clean with a fine file or emery cloth.
• Tighten fully and cover the contact surfaces with 5RX Moly type
grease
Copper or silver-plated aluminium
• Clean with a rough dry cloth.
• Only in the case of obstinate traces of oxidation, clean with a
very fine grain emery cloth taking care not to remove the
surface layer.
• If necessary, restore the surface treatment.
Bare aluminium
• Clean with a metal brush or emery cloth.
• Cover the contact surfaces again immediately with neutral
grease
• Insert the copper-aluminium bimetal with surfaces shined
(copper side in contact with the terminal; aluminium side in
contact with the connection) between the aluminium
connection and the copper terminal.
T2
Bolt
M6
M8
M10
M12
M16
(1) The nominal tightening torque is based on a friction coefficient of the
thread of 0.14 (distributed value the thread is subjected to which, in some
cases, is not negligible). The nominal tightening torque with lubricant is
according to the DIN 43673 Standards.
(2) Oil or grease. The thread and surfaces in contact with the lubricated
heads. Take into account the deviations from the general Standards table
(for example, for systems in contact or terminals) as foreseen in the
specific technical documentation. The thread and surfaces in contact
with the heads of bolts must be slightly oiled or greased, so as to obtain
a correct nominal tightening torque.
5.7 Earthing
For the fixed version circuit breaker, carry out
earthing by means of the special screw marked with
the relative symbol.
Clean and degrease the area around the screw to a
diameter of about 30 mm and, on completion of
assembly, cover the joint again with Vaseline grease.
Use a conductor (busbar or braid) with a cross-
section conforming to the Standards in force.
Recommended tightening torque (
Without lubricant With lubricant (
10.5 Nm 4.5 Nm
26 Nm 10 Nm
50 Nm 20 Nm
86 Nm 40 Nm
200 Nm 80 Nm
5.8 Connection of the auxiliary
circuits
Note: the minimum cross-section of the wires used
for the auxiliary circuits must not be less than the
one used for the internal cabling. Furthermore, they
must be insulated for 3 kV of test.
5.8.1 Fixed circuit breaker
The customer can choose between two types of
auxiliary circuit connections in the circuit breaker.
The first type is supplied as the standard version.
In this case, the auxiliary contacts must be
disassembled from the structure of the circuit
breaker, since their terminals cannot be directly
accessed (consult the installation manual). Part of
the wiring is made during the production phase for
the second type. This means that the customer can
wire up by directly accessing the terminal boxes in
the front part of the circuit breaker. In this case, the
wiring operation is much faster and immediate.
To prevent the cabling wires outside the circuit
)
1
breaker (carried out by the customer) from
)
2
accidentally coming into contact with moving parts
and therefore undergoing damage to the insulation,
it is recommended to fix the
In both types of connection, the wires must pass
through connection while outside the circuit breaker,
the cables must be screened by an appropriate sort
of metallic protection (tube,
duct, ...), which must be earthed.
5.8.2 Withdrawable circuit breakers
The auxiliary circuits of withdrawable circuit breakers
are fully cabled in the factory as far as the connector.
For the external connections, refer to the electric
wiring diagram of the switchgear.
wires.