ABB Relion REQ650, Руководство по применению

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Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Circuit breaker condition monitoring SSCBR - -
12.12.2 Application
SSCBR includes different metering and monitoring subfunctions.
Circuit breaker status
Circuit breaker status monitors the position of the circuit breaker, that is, whether the
breaker is in an open, closed or intermediate position.
Circuit breaker operation monitoring
The purpose of the circuit breaker operation monitoring is to indicate that the circuit
breaker has not been operated for a long time. The function calculates the number of
days the circuit breaker has remained inactive, that is, has stayed in the same open or
closed state. There is also the possibility to set an initial inactive day.
Breaker contact travel time
High travelling times indicate the need for maintenance of the circuit breaker
mechanism. Therefore, detecting excessive travelling time is needed. During the
opening cycle operation, the main contact starts opening. The auxiliary contact A
opens, the auxiliary contact B closes, and the main contact reaches its opening
position. During the closing cycle, the first main contact starts closing. The auxiliary
contact B opens, the auxiliary contact A closes, and the main contact reaches its close
position. The travel times are calculated based on the state changes of the auxiliary
contacts and the adding correction factor to consider the time difference of the main
contact's and the auxiliary contact's position change.
Operation counter
Routine maintenance of the breaker like the lubricating breaker mechanism, is
generally based on a number of operations. A suitable threshold setting, to raise an
alarm when the number of operation cycle exceeds the set limit, helps preventive
maintenance. This can also be used to indicate the requirement for oil sampling for
dielectric testing in case of an oil circuit breaker.
The change of state can be detected from the binary input of the auxiliary contact.
There is a possibility to set an initial value for the counter which can be used to
initialize this functionality after a period of operation or in case of refurbished primary
equipment.
Accumulation of I
y
t
Accumulation of I
y
t calculates the accumulated energy ΣI
y
t where the factor y is
known as the current exponent. The factor y depends on the type of the circuit breaker.
For oil circuit breakers the factor y is normally 2. In case of a high-voltage system, the
factor y can be 1.4...1.5.
1MRK 505 291-UEN A
Section 12
Monitoring
279
Application manual