ABB OVB-SDB, Instructions Manual

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1.0 BREAKER WITH SPRING CHARGED MECHANISM
1.1 General
The operating mechanism has a spring charging device, which can be operated by
motor or manually. The operating device has helical tension spring for closing and
opening. The opening spring is charged automatically when the breaker is closed.
A closed breaker with charged closing spring can thus be operated
OPEN - CLOSE - OPEN without intermediate motorized or manual spring charging,
and the breaker can, therefore, be used for auto re-closing duty cycle.
An indication shows whether the closed spring is charged or not, and the number of
opening operations are recorded by the counter.
The motor can be supplied via station battery, a network or via transformer with a limit
load of at least 500 VA. The motor starts after each closing operation and charges the
closing springs within 15 seconds.
1.2 Construction
The construction of the operating mechanism is shown in Fig D,
Major components of ESH mechanism are:
1. Closing Spring
2. Tripping Spring
3. Geared-Motor
4. Push Button Assembly
5. Closing Coil
6. Tripping Coil.
7. Motor cut-off switch.
8. Auxiliary switch.
9. Spring Charged indication
10. Breaker ON/OFF indications
11. Charging Shaft
12. Power Shaft