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2 Functions
184
7ST6 Manual
E50417-G1176-C251-A3
2.18.2 Testing
The numerical overhead contact line protection 7ST6 allows an easy check of the trip
circuits and the circuit breakers.
2.18.2.1 Functional Description
The test programs as shown in Table 2-8 are available.
The output alarms mentioned must be allocated to the relevant command relays that
are used for controlling the circuit breaker coils.
The test is started using the operator panel on the front of the device or using the PC
with DIGSI
®
. The procedure is described in detail in the SIPROTEC
®
4 System De-
scription, Order No. E50417-H1176-C151. Figure 2-62 shows the chronological se-
quence of one TRIP–CLOSE test cycle. The set times are those stated in Subsection
2.1.3.1 for „Trip command Duration“ and „Circuit Breaker Test“.
Where the circuit breaker auxiliary contacts indicate the status of the circuit breaker or
of its poles to the device via binary inputs, the test cycle can only be initiated if the
circuit breaker is closed.
The alarms of the device show the respective state of the test sequence.
Table 2-8
Circuit breaker test programs
Figure 2-62
TRIP-CLOSE test cycle
Serial
No.
Test programs
Output indications (FNo)
1
TRIP test CB main trip element
„CB-TEST TRIP M“ (13862)
2
TRIP test CB standby trip element
„CB-TEST TRIP B“ (13863)
3
TRIP/CLOSE cycle CB main trip
element
„CB-TEST CLOSE M“ (13864)
4
TRIP/CLOSE cycle CB standby trip
element
„CB-TEST CLOSE B“ (13865)
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