Schweitzer Engineering Laboratories SEL-700G Series, Инструкция по эксплуатации

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5.15
Date Code 20170814 Instruction Manual SEL-700G Relay
Metering and Monitoring
Breaker Monitor
Breaker Monitor
The breaker monitor in the SEL-700G helps in scheduling circuit breaker
maintenance. The breaker monitor is enabled with the enable setting:
EBMONn =
Y
, where n = X or Y
The breaker monitor settings in Table 5.11 are available via the SET G
commands (see Table 6.3). Also refer to BRE n Command (Breaker Monitor
Data) on page 7.22 and BRE n W or R Command (Preload/Reset Breaker
Wear) on page 7.22.
The breaker monitor is set with breaker maintenance information provided by
circuit breaker manufacturers. This breaker maintenance information lists the
number of close/open operations that are permitted for a given current
interruption level. The following is an example of breaker maintenance
information for a 25 kV circuit breaker. The breaker maintenance information
in Table 5.10 is plotted in Figure 5.17.
Connect the plotted points in Figure 5.17 for a breaker maintenance curve. To
estimate this breaker maintenance curve in the SEL-700G breaker monitor,
three set points are entered for breaker n, where n = X or Y:
Table 5.10 Breaker Maintenance Information for a 25 kV Circuit Breaker
Current Interruption Level (kA)
Permissible Number of
Close/Open Operations
a
a
The action of a circuit breaker closing and then later opening is counted as one close/open
operation.
0.00–1.20 10,000
2.00 3,700
3.00 1,500
5.00 400
8.00 150
10.00 85
20.00 12
Set Point 1
COSP1n maximum number of close/open operations with
corresponding current interruption level.
Set Point 2
COSP2n number of close/open operations that correspond to
some midpoint current interruption level.
Set Point 3
COSP3n number of close/open operations that correspond to
the maximum current interruption level.