Replacement Of Operating Mechanism - ABB HPA 12kV Instruction For Installation, Service And Maintenance

Reasons for changing the damping device can be oil leaks normally the device does
not need maintenance. Repair of the device must not be carried out. Never operate
the breaker without the damping device as damage to the breaker can occur.
Changing of damping device is carried out as follows:
1. Move the breaker out onto the door.
2. Close the breaker if the damping device is to be changed.
3. Lock and secure the release mechanism according to fig. 14. Be extremely
careful that hands are kept clear of the mechanism and the springs in case of
release.
4. Loosen the devices safety nuts. Withdraw the device from the plate. No other
units need to be loosened. If other units are loosened, there is a risk of the
springs being released. The lower part of the device is pulled out through a
hole in the plate.
5. Insert the new damping device. Adjust it so that at the "ON" position, the step
of the shaft of damping device shall be in line with the damping device
housing.
6. Tighten the safety nuts.
7. Loosen the locking for release mechanism.

1.4.7 Replacement of operating mechanism

1. Remove the breaker from the cubicle and keep it on a suitable foundation.
2. Loosen the operating devices cover, see fig. 15. Lift off cover.
3. Loosen the sliding contacts screws, pin, connecting cables and the 4
screws, see fig.
4. Completely withdraw the operating device.
(Locking of the release mechanism for spring)
Fig - 14
(22)