16
PSERC
Better
Information
Multiple
Data Sources
CB monitors: control circuit signals, vibration, gas pressure
Digital fault
recorders:
“A” and “B” contacts, phase
current changes
Protective relays: duty cycle currents, I2 · t
Temporal Analysis
Sequence of control signal initiations and changes in
circuit breaker status
Sequence and correlation of changes of the status
contacts and CB currents
Timing of CB operations and current interruptions
Historical
Assessment
Number of operations and assessment of
the opening/ closing times
Consistency of
“A” and “B” contacts and their
reliability
Assessment of
the duty cycle over long time