ABB OVB-SDB, Instructions Manual

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5.0 COMMISSIONING
5.1 General checks
All necessary settings and adjustments have been made and the units have been fully
tested both electrically and mechanically before dispatch at the factory. Hence,
normally no setting and adjustment are required at the site.
5.2 Wiring
Unit wiring is identified by numbered ferrules. Any external wiring required should be
done at site as per the relevant schematic diagram fig.5, Page 54.
5.3 Cleaning
All the insulating parts, porcelain insulator should be cleaned either with chamois
leather or equivalent cloth. These insulating parts should not be cleaned with a material,
which will deposit loose fibers.
5.4 Electrical checking
B Circuit breaker in close position
Between terminals and earth.
If the insulation resistance values are satisfactory (more then 100 mega ohms),
then a high voltage test with 28kV (in case of 12kV) and 50kV (in case of 15kV )
for 1 minute shall be done for other configurations, similar to Megger test.
If the insulation resistances are appreciably lower then 100 mega ohms, an
inspection for insulation fault should be made before proceeding with high
voltage test.
5.4.1 Low voltage circuits
The auxiliary circuit wiring shall be checked with a 500V or 1kV Megger. The
insulation resistance shall be about 2 mega ohms.
5.4.2 High voltage circuits
Prior to commissioning the breaker, or putting it back into service after a
maintenance outage, the insulation resistance of the high voltage circuit shall be
checked using a 5kV Megger.
The breaker shall be earthed and isolated from other equipment before doing this
test. All insulation parts shall be clean and dry.
The insulation resistance shall be checked for the following configuration,
A Circuit breaker in open position
Across open contact of each phase.
Between top terminal and earth of each phase.