ABB Relion 670 Series Applications Manual page 395

1MRK 505 370-UUS Rev. K
Accumulated energy
Monitoring the contact erosion and interrupter wear has a direct influence on the required maintenance
frequency. Therefore, it is necessary to accurately estimate the erosion of the contacts and condition of
interrupters using cumulative summation of I
energy values were accumulated using the current value and exponent factor for CB contact opening
duration. When the next CB opening operation is started, the energy is accumulated from the previous
value. The accumulated energy value can be reset to initial accumulation energy value by using the
Reset accumulating energy input, RSTIPOW.
Circuit breaker operation cycles
Routine breaker maintenance like lubricating breaker mechanism is based on the number of operations.
A suitable threshold setting helps in preventive maintenance. This can also be used to indicate the
requirement for oil sampling for dielectric testing in case of an oil circuit breaker.
Circuit breaker operation monitoring
By monitoring the activity of the number of operations, it is possible to calculate the number of days the
breaker has been inactive. Long periods of inactivity degrade the reliability for the protection system.
Circuit breaker spring charge monitoring
For normal circuit breaker operation, the circuit breaker spring should be charged within a specified time.
Detecting a long spring charging time indicates the time for circuit breaker maintenance. The last value of
the spring charging time can be given as a service value.
Circuit breaker gas pressure indication
For proper arc extinction by the compressed gas in the circuit breaker, the pressure of the gas must be
adequate. Binary input available from the pressure sensor is based on the pressure levels inside the arc
chamber. When the pressure becomes too low compared to the required value, the circuit breaker
operation is blocked.
14.4.3 Setting guidelines
The breaker monitoring function is used to monitor different parameters of the circuit breaker. The
breaker requires maintenance when the number of operations has reached a predefined value. For
proper functioning of the circuit breaker, it is also essential to monitor the circuit breaker operation, spring
charge indication or breaker wear, travel time, number of operation cycles and accumulated energy
during arc extinction.
Busbar protection REB670
Application manual
Since there is no current measurement in SAM600-IO, evaluation of the following
parameters are not possible in the circuit breaker condition monitoring function (SSCBR):
• Circuit breaker status
• Remaining life of the circuit breaker
• Contact erosion estimation
• Circuit breaker contact travel time
Ensure that OPENPOS, CLOSEPOS, INVDPOS, CBLIFEAL, IPOWALPH, IPOWLOPH,
TRVTOPAL and TRVTCLAL signals are not used in SAM600–IO.
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y
. The factor "y" depends on the type of circuit breaker. The
Section 14
Monitoring
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