AIR AND OIL CIRCUIT BREAKER PREVENTIVE MAINTENANCE
Adapted from Power O&M Bulletin No. 19
Maintenance Schedules and Records October 1965, Section 10
NOTE: Unless the maintenance interval is specified, conduct preventive
maintenance annually (indicated by *) or as the equipment becomes available
during an outage. For other maintenance requirements, see section 9, "Circuit
Breakers," in the body of this FIST volume.
* Check foundation for cracks and settling. A shift of the breaker tanks may break
bushings or cause misalignment of contacts or binding of operating mechanism.
Frame and Tanks
Daily or Weekly Check for oil leaks and note tank temperature by touch.
Oil Valves and Plugs
* Check condition of paint and repaint as necessary. Inspect oil valves and plugs and
stop oil leaks. See that oil drain valves that can be operated without wrenches are
plugged or locked to prevent unauthorized opening. Tighten bolts. Clean interior of
tanks. Inspect underside of cover for moisture and rust, and clean and repaint as
necessary. Check tank liners and interphase barriers.
Oil Levels and Gages
Daily or Weekly Check oil level in gages of the tanks and oil-filled bushings.
Replenish oil if below normal.
* Clean dirty gage glasses and connections into tank. Drain out and replace bushing
oil if dirty or discolored.
Breathers and Vents
Daily or Weekly Check for external obstructions to breakers and vents.
* Check to see that screens and baffles in vents or breathers are not obstructed or