²
A protection function must not have been picked up in the circuit-breaker protection function group
responsible for the circuit breaker.
[scCBTest3p, 1, en_US]
Figure 11-5 Settings for the Circuit-Breaker Test
Figure 11-6 shows the progression over time of an open-close cycle. If you activated the (_:6151:102)
Trip only option, the close command will not be executed and the dead time will not be taken into
account.
If a circuit-breaker auxiliary contact is connected, the function waits for the indication circuit breaker Posi-
tion = open after the trip command is generated. When the indication Position = open is received, the
close command is transmitted after a dead time (parameter (_:6151:101) Dead time) for an open-close
cycle. If the feedback from the circuit-breaker positions is not received within the maximum transmission time
(Dead time + 2 · Output time + 5 s), the circuit-breaker test is aborted and considered to be failed. The
proper functioning of the circuit breaker is monitored via the feedback on the circuit-breaker positions.
[dwcbch03-300913, 1, en_US]
Figure 11-6 Progress over Time of a Circuit-Breaker Test Cycle
Use the (_:6151:103) Consider current criterion parameter to ensure the circuit-breaker test is
only carried out when the current flowing through the circuit breaker does not exceed a specific current
threshold (parameter (_:6151:104) Current threshold). Otherwise, the circuit-breaker test is not
started.
²
If the current-flowcriterion is deactivated, the current threshold is not evaluated. The circuit-breaker test
is performed irrespective of the current-flow level through the circuit breaker.
NOTE
The circuit-breaker test does not perform a synchrocheck even if the synchrocheck has been configured in
the protection-function groups for circuit breakers. This can cause stability problems in the system during a
3-pole interruption. Therefore, a 3-pole circuit-breaker test should be very short, or not performed at all
under load.
You can start the test program as follows:
•
Via the device-control panel
•
Via DIGSI
•
Via communication protocols
•
Via control commands, which you can also connect in the CFC
The following figure illustrates operation of the circuit-breaker test in DIGSI.
Functional Tests
11.6 Circuit-Breaker Test
SIPROTEC 5, Overcurrent Protection, Manual 1383
C53000-G5040-C017-8, Edition 07.2017
To Next Page
Loading...
