ABB RELION 620 Series Technical Manual page 580

Section 6
Supervision functions
6.1.6
574
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 288 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.
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.
Signals
Table 418: 52CM Input signals
Name Type
I_A SIGNAL
I_B SIGNAL
I_C SIGNAL
BLOCK BOOLEAN
Table continues on next page



= − . 2 2609

f


r
Default Description
0 Phase A current
0 Phase B current
0 Phase C current
0=False Block input status
1MAC504801-IB E
(Equation 88)
620 series ANSI
Technical Manual