Application and Setting Notes
Parameter: Switch On or Off Additional Plausibility Release Criteria
•
Default setting (_:101) Plausibility via 50BF fct. = no
•
Default setting (_:102) Plaus. via open/trip cmd = no
•
Default setting (_:103) Plaus. via binary input = no
When using the plausibility release, the start condition and the release condition instead of only the start
condition must be present to start the current monitoring regarding restriking. Since the current threshold
value is set below the operating current, a false start would directly cause tripping. Thus, the plausibility
release strongly reduces the risk that a falsely given start criterion leads to a wrong tripping of the superordi-
nated circuit breaker.
3 different release criteria are available. You can use one or more than one or none of them. The selection
depends on the application.
NOTE
When using release criteria, it must be ensured that the criteria are given under all the conditions where
the Circuit-breaker restrike protection shall be started. If you choose no release criteria, the release is
permanently given.
•
Open/trip command by the device
Use this criterion in case that all control or trip commands are given by the protection device.
NOTE
Opening the circuit breaker manually without using the device will not release the start of the Circuit-
breaker restrike protection.
•
Pickup of the Circuit-breaker failure protection
Use this criterion if the Circuit-breaker restrike protection should only be started in case that the Circuit-
breaker failure protection was started (picked up) before.
NOTE
Opening the circuit breaker by control or manually will not trigger the Circuit-breaker failure protection.
Consequently the Circuit-breaker restrike protection cannot be released either.
•
Binary input signal
Use this option if neither of the above 2 release criteria fit the application and you want to define your own
release criterion.
Input signals:
>Start, >release, >Stop
Input Signals
Description
>Start
This input signal allows to start the monitoring, for example, via
protocol commands from a master (by use of a CFC chart) or by other
specific conditions.
>release
This input signal allows to define specific release conditions by use of a
CFC chart. Also refer to Parameter: Switch On or Off Additional Plausi-
bility Release Criteria , Page 857.
>Stop
This input signal allows to stop the monitoring, for example, via
protocol commands from a master (by use of a CFC chart) or by other
specific conditions.
6.42.4
Protection and Automation Functions
6.42 Circuit-Breaker Restrike Protection
SIPROTEC 5, Overcurrent Protection, Manual 857
C53000-G5040-C017-8, Edition 07.2017
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