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Closing Solenoid Air Cylinder, Motor, or Spring
Weekly Visual inspection to see that equipment is in operating condition. Drain
condensation from air cylinder.
* Observe mechanism during several closing operations to see that everything is in
proper working order. Check solenoid plunger for sticking in guides. Check coil
resistance and insulation resistance. Dismantle air cylinder and clean and
relubricate. Check motor. Check closing springs for proper tension and closing
energy.
Manual Operating Device
* See that manual operating lever or jack is kept on hand and in usable condition.
See that breaker will close with it.
Latch and Trip Mechanism
Weekly Visual inspection to see that mechanism is in operating condition.
* Observe mechanism during several tripping operations to see that everything is in
working order. Check pins, bearings, and latches for wear, binding, and
misalignment. Clean and relubricate. Check latch carefully to see that it is not
becoming worn so that it would unlatch from vibration or stick and fail to trip.
Tighten bolts and screws.
Tripping Solenoid
Weekly Visual inspection to see that solenoid trip device is in operating condition.
* Observe operation during electrical tripping. See that full energy, snappy action of
plunger is obtained. Check plunger for sticking in guides. Check coil and insulation
resistance.
Solenoid Valves
* Check for condition of valve seat and refit as necessary. See that moving parts are
free to operate. Check resistance and insulation resistance of solenoid coil.
Auxiliary Switches
* Check condition of contacts and refinish with fine file if burned or corroded. Check
contact springs, operating rods, and levers. Check closing and opening position with
respect to main contacts while breaker is being slowly closed and opened manually.
Certain auxiliary contacts used for special purposes may require close adjustment in
this respect.