ABB 615 series Technical Manual page 898

Section 7
Condition monitoring functions
892
B

log

A

Directional Coef
=
I

log

I

A070794 V2 EN
I Rated operating current = 630 A
r
I Rated fault current = 16 kA
f
A Op number rated = 30000
B Op number fault = 20
Calculation for estimating the remaining life
Figure 465 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 30,000/60=500 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 15,000-500=14,500 at the rated operating current.
Remaining life reduction =
GUID-5AA23DAD-AAF0-4D03-844F-216C80F80789 V1 EN
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.



. 2 2609
= −

f

r

Directional Coef
−
I
 
 
I
 
r
1MAC059074-MB A
(Equation 162)
(Equation 163)
615 series ANSI
Technical Manual