12
Maintenance or Test
Recommended Interval
Reference
Preventive maintenance
Dependent on charger type
FIST Volume 3-6
Infrared scan
Annually
NFPA 70B 18.17
Bushings are critical components of circuit breakers and transformers. Bushing
maintenance is usually conducted at the same time maintenance is performed on the
circuit breaker or transformer, or at least during an outage on that equipment.
maintenance is usually conducted at the same time maintenance is performed on the
circuit breaker or transformer, or at least during an outage on that equipment.
Refer to the circuit breaker and transformer maintenance sections of this document for
bushing maintenance requirements.
bushing maintenance requirements.
Buswork conducts current from one part of the powerplant or switchyard to another.
Buswork is usually constructed of flat or round copper or aluminum busbar and can
be either isolated-phase or nonsegregated. Except for infrared scanning, bus
maintenance must be conducted de-energized. Standoff buswork insulators provide
isolation of "live" power circuits from ground and other circuits. Failure of insulators
will cause a power system fault and a forced outage.
Buswork is usually constructed of flat or round copper or aluminum busbar and can
be either isolated-phase or nonsegregated. Except for infrared scanning, bus
maintenance must be conducted de-energized. Standoff buswork insulators provide
isolation of "live" power circuits from ground and other circuits. Failure of insulators
will cause a power system fault and a forced outage.
Maintenance or Test
Recommended Interval
Reference
Review equipment ratings
5 years
NERC Planning Standard
External visual inspection
Check and tighten connections
Check and clean enclosures
Check and tighten connections
Check and clean enclosures
Annually
NFPA 70B, 6-1.3
NFPA 70B, 21-4.3
NFPA 70B, 21-4.3
High potential (to ground and
between phases) or Doble "tip up"
between phases) or Doble "tip up"
1-6 years
Ambient dependent
Ambient dependent
NFPA 70B, 21-5.6.2
Infrared scan
Annually
NFPA 70B, 21-5.2.2