ABB OVB-SDB, Instructions Manual

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In case of magnetic actuator, the charging circuit gets the supply and charges the
capacitor. As the capacitor is charged to 80 V, the charging unit will cut off the supply to
the capacitor and capacitor charged indication will appear. Now the breaker is ready for
closing operation and the closing operation can be done as described earlier.
5.8 Starting conditions
The erected circuit breaker is isolated from high voltage system and earthed according to
regulation. The control current circuit is connected to the low-voltage system.
5.9 Function test
Check correspondence with the customer related diagram and that the connections have
been made correctly. Then the trial switching can be carried out from a protected position.
The trial switching may be performed if:
The circuit breaker is isolated from the high voltage and earthed according to
regulations.
The spring tension indicator of the spring operated mechanism indicates the
position “tensioned”
5.10 Trial switching operations
Give few Close/Open command and see that the breaker Close/Open Properly.
5.11 Anti-pumping device
Issue a "close" command by applying a control voltage to terminal 101 & 102 leave the
voltage applied. The breaker will close.
Issue open command by applying a voltage to terminal 103 &104 The breaker will open.
After the interruption by OPEN command the circuit breaker should not re-close in spite
of the CLOSE command still being present.
Note:
The ESH operating mechanism on OVB-SDB circuit breaker is fitted with a mechanical anti-
pumping device, which prevents re-closing due to either electrical or mechanical commands.
5.12 Check of heaters:
Measure the resistance or apply voltage and measure the current, when the thermostat
controlled additional heater is installed, check the adjustment of thermostat.
5.13 Concluding Work:
Remove all test and measuring equipment.
Connect circuit breaker to high voltage power lines.
Make sure that safety regulations are followed.
Take the breaker in to service.