ABB REF615 Applications Manual page 210

Section 8
Condition monitoring functions
204
The equation shows that there are 30,000 possible operations at the rated operating
current of 630 A and 20 operations at the rated fault current 16 kA. Therefore, if the
tripping current is 10 kA, one operation at 10 kA is equivalent to 30,000/500=60
operations at the rated current. It is also assumed that prior to this tripping, the
remaining life of the circuit breaker is 15,000 operations. Therefore, after one
operation of 10 kA, the remaining life of the circuit breaker is 15,000-60=14,940 at
the rated operating current.
Spring charged indication
For normal operation of the circuit breaker, the circuit breaker spring should be
charged within a specified time. Therefore, detecting long spring charging time
indicates that it is time for the circuit breaker maintenance. The last value of the spring
charging time can be used as a service value.
Gas pressure supervision
The gas pressure supervision monitors the gas pressure inside the arc chamber. When
the pressure becomes too low compared to the required value, the circuit breaker
operations are locked. A binary input is available based on the pressure levels in the
function, and alarms are generated based on these inputs.
1MRS756378 D
REF615
Application Manual