EMR-5000
IM02602012E
Switchgear Wear Curve
In order to keep the switchgear in good working condition, the switchgear needs to be monitored. The switchgear
health (operation life) depends above all on:
The number of CLOSE/OPEN cycles.
The amplitudes of the interrupting currents.
The frequency that the
switchgear
operates (Operations per hour).
The User has to maintain the switchgear accordingly to the maintenance schedule that is to be provided by the
manufacturer (switchgear operation statistics). By means of up to ten points that the user can replicate the switchgear
wear curve within menu [
Control/SG/SG[x]/SGW]
. Each point has two settings: the interrupt current in kilo amperes
and the allowed operation counts. No matter how many points are used, the operation counts the last point as zero. The
protective relay will interpolate the allowed operations based on the switchgear wear curve. When the interrupted
current is greater than the interrupt current at the last point, the protective relay will assume zero operation counts.
www.eaton.com
455
0.1
1
10
100
1
10
100
1 10
3
×
1 10
4
×
0.0
10000
1.2
10000
8.0
150
20.0
12
20.0
0
Breaker Maintenance Curve for a typical 25kV Breaker
N
u
m
b
e
r
of
O
p
e
ra
tio
n
s
Interrupted Current in kA per operation
