Trip Bypass [50Bf/62Bf]; Principle - General Use - Eaton EMR-3MP0 Installation, Operation And Maintenance Manual

4 Protective Elements

4.15 Trip Bypass [50BF/62BF]

4.15 Trip Bypass [50BF/62BF]
4.15.1 Principle – General Use
The »Trip Bypass« module is used to provide backup protection in the event that a
breaker fails to operate properly during fault clearing. This signal is to be used to trip the
upstream breaker (e. g. infeed of a busbar) either via an output relay or via
communication.
Supervision Scheme
The module must be activated via setting [Protection Para / Trip Bypass] »Function« =
"Active".
A supervision timer is started as soon as the »Trip Bypass« module is triggered by a
General Trip signal, »Prot . Trip«. A Breaker Failure is detected and a signal is issued if the
measured current does not fall below the fixed device-internal threshold 0.1⋅In within
1 second.
The »Trip Bypass« module is recommended if Breaker Failures have to be detected while
there is no or not much load flow (small currents).
Start/Trigger of the Trip Bypass Timer
The supervision timer is started, once the »Trip Bypass« module is triggered. This is
reported by the status signal »Trip Bypass . Pickup«. Even if the Trigger signal (i. e. the
General Trip) drops again, the timer continues.
After the timer has elapsed, the module issues the signal »Trip Bypass . Trip«. This signal
can be used to trip the upstream breaker (backup).
Stopping the Trip Bypass: The timer is stopped if the opening of the breaker is detected,
i. e. if the current falls below the current threshold. The »Trip Bypass« module remains
within the "rejected" state until the trigger signal drops off.
Detecting a Breaker Failure: The Breaker Failure signal »Trip Bypass . Trip« is set if the
current doesn't fall below the threshold.
Reject state of the »Trip Bypass« module: The »Trip Bypass« module switches into the
"rejected" state if the General Trip trigger signal is still active while the open position of
the breaker has been detected successfully.
Readiness for Operation: The »Trip Bypass« module switches back into the stand-by if the
General Trip trigger signal drops off. This is reported by the status signal »Trip Bypass .
Waiting for Trigger«.
Breaker Failure Lockout
The signal of the Breaker Failure is latched. This signal can be used to block the breaker
against a switching on attempt.
190 www.eaton.com EMR-3MP0