Technical description
3 Supporting functions
3.5 Circuit breaker condition
monitoring
VM50.EN004
VAMP 24h support phone +358 (0)20 753 3264
119
10
20
50
100
1000
10000
100000
100
200
500 1000
10000
100000
Number
of
permitted
operations
Breaked current (A)
CBWEARcharacteristics
Figure 3.5-1. An example of a circuit breaker wearing characteristic graph.
Table 3.5-1. An example of circuit breaker wearing
characteristics in a table format. The values are taken from
the figure above. The table is edited with VAMPSET under
menu "BREAKER CURVE".
Point Interrupted
current
(kA)
Number of permitted
operations
1
0 (mechanical age)
10000
2
1.25 (rated current)
10000
3
31.0 (maximum breaking current)
80
4 100
1
5 100
1
6 100
1
7 100
1
8 100
1
Setting alarm points
There are two alarm points available having two setting
parameters each.
Current.
The first alarm can be set for example to nominal current of
the CB or any application typical current. The second alarm
can be set for example according a typical fault current.
Operations left alarm limit
An alarm is activated when there are less operation left at
the given current level than this limit.
Any actual interrupted current will be logarithmically weighted
for the two given alarm current levels and the number of
operations left at the alarm points is decreased accordingly.
When the "operations left" i.e. the number of remaining
operations, goes under the given alarm limit, an alarm signal is
issued to the output matrix. Also an event is generated
depending on the event enabling.