ABB REU 610 Technical Reference Manual page 23

1MRS755972
Voltage Relay
Technical Reference Manual - ANSI Version
The high-set overvoltage element 59P-2 can be set to be based on either
Conventional voltage measurement (59P-2 mode selected), or
*
Calculated negative phase-sequence voltage (47 mode selected).
*
The selection between these modes is made either by using HMI or parameter
S7, the default setting being conventional measurement. Element 27D (PPS)
and 47 (NPS) cannot be used at the same time.
Element 59P-2 can be set out of operation in SGF3/1. 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 an overvoltage element by
applying a digital input signal to the relay.
Overvoltage protection based on conventional voltage
measurement
Both the low-set and the high-set overvoltage element can independently be
set to pickup and trip when one of the three voltages or all the voltages rise
above the set start value. By default, both elements operate when one of the
three voltages rise above the set pickup value. The selection is made in SGF4/
5 and SGF4/6.
When the phase-to-phase voltage values exceed the set pickup value of the
low-set element 59P-1, the element generates a pickup signal after a ~ 60 ms'
pickup time. When the set operate time at definite-time characteristic or the
calculated operate time at IDMT characteristic elapses, the element generates
a trip signal.
Element 59P-1 has a settable resetting time (both at definite-time and IDMT
characteristics), 59P-1 RESET, for reset coordination with existing
electromechanical relays or for reducing fault clearance times of recurring,
transient faults. If element 59P-1 has picked up and the phase-to-phase
voltages fall below the set pickup value of the element, the pickup of the
element remains active for the set resetting time. If the phase-to-phase
voltages exceed 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 59P-1 has
already tripped, the element is reset in 70 ms after the phase-to-phase voltages
have fallen below 0.5 times the set pickup value of the element. However, if
element 59P-1 has already tripped and the phase-to-phase voltages have
fallen below the set pickup value of the element, but not below 0.5 times the
set pickup value, the element is reset when the set resetting time is expired.
REU 610
23