Circuit-Breaker Failure Protection - ABB REU 610 Technical Reference Manual

REU 610
5.1.4.5.
28
Voltage Relay
Technical Reference Manual - ANSI Version
When the residual voltage exceeds the set pickup value of the low-set element
59N-1, the element generates a pickup signal after a ~ 70 ms' pickup time.
When the set operate time elapses, the element generates a trip signal.
Element 59N-1 has a settable resetting time 59N-1 RESET for reset
coordination with existing electromechanical relays or for reducing fault
clearance times of recurring, transient faults. If element 59N-1 has picked up
and the residual voltage falls below the set pickup value of the element, the
pickup of the element remains active for the set resetting time. If the residual
voltage exceeds the set pickup value again while the timer is running, the
timer is cleared and the pickup of the element remains active.
Consequently, the set resetting time ensures that when the element picks up
because of voltage spikes, it is not immediately reset. If element 59N-1 has
already tripped, the element is reset in 50 ms after the residual voltage falls
below 0.5 times the set pickup value of the element. However, if element
59N-1 has already tripped and the residual voltage has fallen below the set
pickup value of the element, but not below 0.5 times the set pickup value, the
element is reset after the set resetting time (59N-1 RESET) has expired.
When the residual voltage exceeds the set pickup value of the high-set
element 59N-2, the element generates a pickup signal after a ~ 60 ms' pickup
time. When the set operate time has elapsed, the element generates a trip
signal.
If element 59N-2 has picked up and the residual voltage falls below the set
pickup value of the element, the pickup of the element remains active for 100
ms. If the residual voltage exceeds the set pickup value again while the timer
is running, the timer is cleared and the pickup of the element remains active.
If element 59N-2 has already tripped, the element is reset in 50 ms after the
residual voltage falls below 0.5 times the set pickup value of the element.
However, if element 59N-2 has already tripped and the residual voltage has
fallen below the set pickup value of the element, but not below 0.5 times the
set pickup value, the element is reset after the 100 ms' resetting time has
expired.
Elements 59N-1 can be set out of operation in SGF3/3 and element 59N-2
can be set out of operation in SGF3/4. This state is indicated by dashes on the
LCD and by 999 when the set pickup value is read via serial communication.
It is possible to block the tripping of a residual overvoltage
element by applying a digital input signal to the relay.

Circuit-breaker failure protection

The circuit-breaker failure protection (CBFAIL) detects situations where the
trip remains active although the circuit breaker should have operated.
1MRS755972