DISTRIBUTION SOLUTIONS
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8.1. General procedures
Before putting the circuit breaker into service, carry
out the following operations:
• check tightness of the power connections at the
circuit breaker terminals;
• establish the setting of the primary electronic
overcurrent release (if provided);
• check that the value of the power supply voltage of
the auxiliary circuits is between 85% and 110% of
the rated voltage of the electrical accessories;
• check that no foreign bodies, such as bits of
packing, have got into the moving parts;
• check that there is a sufficient exchange of air in
the installation place to avoid overtemperatures;
• also carry out the checks indicated in table T3.
T3
—
8. Putting into service
All the operations regarding putting
into service must be carried out by ABB
personnel or by suitably qualified
customer personnel with in-depth
knowledge of the apparatus and of the
installation.
Should the operations be prevented, do
not force the mechanical interlocks and
check that the operating sequence is
correct.
The operating forces which can be
applied for racking-in withdrawable
circuit breakers are indicated in
paragraph 7.6.
ITEM INSPECTED
PROCEDURE
POSITIVE CHECK
1
Insulation resistance.
Medium voltage circuit
With a 2500 V megger, measure the insulation
resistance between the phases and the
exposed conductive part of the circuit
Auxiliary circuits
With a 500 V megger (if the apparatus
installed allows this), measure the insulation
resistance between the auxiliary circuits and
the exposed conductive part.
The insulation resistance should be at least 50
Mohm and in any case constant over time.
The insulation resistance should be a few
Mohm and in any case constant over time.
2
Auxiliary circuits.
Check that the connections to the control
circuit are correct: proceed at the relative
power supply.
Operations and signals are normal.
3
Manual operating
mechanism.
Carry out a few closing and opening
operations (see cap. 6).
N.B. Supply the
undervoltage release and the locking magnet
on the operating mechanism at the relative
rated voltage (if provided).
The operations and the relative signals take
place normally.
4
Motor operator (if
provided).
Supply the spring charging geared motor at
the relative rated voltage.
Carry out a few closing and opening
operations
N.B. Supply the undervoltage release and the
locking magnet on the operating mechanism
at the relative rated voltage (if provided).
The springs are charged normally.
The signals are normal.
With the springs charged, the geared motor
stops.
The geared motor recharges the springs after
each closing operation.
5
Undervoltage release
(if provided).
Supply the undervoltage release at the relative
rated voltage and carry out the circuit breaker
closing operation.
Cut off power to the release.
The circuit breaker closes normally.
The signals are normal.
The circuit breaker opens.
The signalling changes over.
6
Shunt opening release
and additional shunt
opening release (if
provided).
Close the circuit breaker and supply the shunt
opening release at the relative rated voltage.
The circuit breaker opens normally.
The signals are normal.
7
Shunt closing release (if
provided).
Open the circuit breaker and supply the shunt
closing release at the relative rated voltage.
The circuit breaker closes normally.
The signals are normal.
Summary of Contents for Vmax 12
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