Siemens 7SR18 Solkor - Section 4: Supervision Functions; CB Fail (50 BF)

7SR18 Commissioning & Maintenance Guide
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Section 4: Supervision Functions
4.1 CB FAIL (50BF)
Figure 4.1-1 CB Fail
Current Inputs: I
L1
(I
A
), I
L2
(I
B
), I
L3
(I
C
), I
L4
Disable:
Map Pickup LED: 50BF-n - Self Reset
The circuit breaker fail protection time delays are initiated either from:
A binary output mapped as Trip Contact in the OUTPUT CONFIG>BINARY OUTPUT CONFIG menu,
or
A binary input mapped as 50BF Ext Trip in the INPUT CONFIG>INPUT MATRIX menu.
Or
A binary input mapped as 50BF Mech Trip in the INPUT CONFIG>INPUT MATRIX menu.
Apply a trip condition by injection of current to cause operation of a suitable protection element. Allow current to
continue after the trip at a level of 110% of the 50BF Setting current level on any phase. Measure the time for
operation of 50BF-1 Delay and 50BF-2 Delay. Repeat the sequence with the 50BF CB Faulty input energised and
ensure the 50BF-1 and 50BF-2 outputs operate without delay, by-passing the timer delay settings.
Repeat the sequence with current at 90% of the 50BF Setting current level after the element trip and check for no
CB Fail operation.
Repeat the sequence by injecting the current to I4 and using the 50BF-I4 Setting.