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8.5
Date Code 20070117
Instruction Manual
SEL-351-5, -6, -7 Relay
Breaker Monitor, Metering, and Load Profile Functions
Breaker Monitor
Figure 8.2
Breaker Maintenance Curve for a 25 kV Circuit Breaker
, note that the breaker maintenance curve levels off horizontally
below set point KASP1, COSP1. This is the close/open operation limit of the
circuit breaker (COSP1 = 10000), regardless of interrupted current value.
10,000
100%
1000
2
3
4
5
6
7
8
9
100
2
3
4
5
6
7
8
9
10
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7 8 9
50
40
30
20
10
.5
Number of Close/Open Operations
kA Interrupted per Operation
KASP1 = 1.2
COSP1 = 10000
KASP2 = 8.0
COSP2 = 150
KASP3 = 20.0
COSP3 = 12
Summary of Contents for SEL-351-5
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