Breaker Health - GE 845 Instruction Manual

MONITORING

Breaker Health

4–270
The 845 relay provides breaker health information by monitoring and analyzing the
operation count, arcing energy of breaking current, arcing time, tripping time, closing time
and spring charging time if applicable. The breaker health status depends on many
factors, such as permissible operation number, magnitude of breaking current, mechanical
wear and contact wear.
The operation count is able to give direct information by comparing it with the permissible
operation number. The longer tripping time and closing time can provide an approximate
estimation of trip/close coils and mechanical wear. The increasing spring charging time
may imply developing problems in motor and spring mechanisms. Meanwhile, the increase
in arcing energy of the breaking current may reflect the possibility of contact wear. Longer
arcing time may suggest the loss of dielectric strength in the arc chamber. If the arcing
energy or any of the time intervals is above the related Pickup levels for the use-defined
times, the ALARM LED is lit.
The scheme is equipped with three incomplete sequence timers for Trip/Close time, arc
time and spring charge time respectively. So it automatically resets the related time
interval after the programmed delay.
A breaker operation function is also included, where breaker operation failure is caused by
either of the following conditions:
• The breaker does not respond to a Trip command within the programmed breaker
operation delay time.
• The breaker does not respond to a Close command within the programmed time.
Path:
Setpoints > Monitoring > Breaker > Breaker 1 Monitor > Breaker Health
FUNCTION
Range: Disabled, Alarm, Latched Alarm, Configurable
Default: Disabled
845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 4: SETPOINTS