ABB REF 545 Product Guide

Feeder Terminal REF 541, REF 543, REF 545.
1MRS750443-MBG
65
Fig. 18 Symbol notations, part I
3I > 50/51
3I> 67
I
0
> 67N
I
0-0
>
51N
I
0
>
50N/51N
51N
SEF
3I >
50/51
51B
3U > 59
3U < 27
U
0
>
59N
3I
2f
>
68
CBFP * /62
0
I
79
f <
81U
DI>
46
49F
3
3D I >
87T
DI
0
>
87N
I
02f
>
68
= multiple-stage three-phase overcurrent protection, low-set, high-set and instantaneous
stage available
= multiple-stage three-phase directional overcurrent protection, low-set, high-set and
instantaneous stage available
= instantaneous stage for earth-fault protection, to operate in the event of a double earth
fault in isolated or impedance earthed networks
= multiple-stage directional earth-fault protection, low-set, high-set and instantaneous
stage available
= multiple-stage earth-fault protection, low-set, high-set and instantaneous stage
available
= low-set stage for sensitive earth-fault protection, to operate in the event of a high
resistive earth fault in effectively or low-impedance earthed networks
= multiple-stage three-phase overcurrent protection, one stage dedicated for blockable
busbar overcurrent protection
= three-phase overvoltage protection, low-set and high-set stage available
= three-phase undervoltage protection, low-set and high-set stage available
= multiple-stage residual overvoltage protection, low-set, high-set and instantaneous
stage available
= inrush detection based on the 2nd harmonic content of phase currents, applied for
preventing possible unnecessary operation of overcurrent or earth-fault protection
during transformer switching-in or to start cold load pick-up logic
= phase discontinuity protection
= underfrequency protection/load shedding scheme
= thermal overload protection for feeders
SYNC 25
= multiple-shot auto-recloser
= circuit breaker synchro-check/direction of energizing check function
= differential protection for transformers
= restricted earth-fault protection, low- or high-impedance type
= inrush detection based on the 2nd harmonic content of neutral current, applied to
prevent possible unnecessary operation of the earth-fault protection during transformer
switching-in
= circuit-breaker failure protection
SYMNOT1

ABB REF 545 Specifications

General

Brand	ABB
Model	REF 545
Category	Touch terminals
Language	English