ABB REG670 - Multi-Breaker Applications

Reactor
REFPDIF
I3PW1CT1
I3P
IdN/I
IEC09000112-4.vsd
IEC09000112-4 V2 EN
Figure 75: Connection of restricted earth-fault, low impedance function
REFPDIF for a solidly earthed reactor
7.4.2.5 Multi-breaker applications
Multi-breaker arrangements including ring, one and a half breaker, double breaker
and mesh corner arrangements have two sets of current transformers on the phase
side. The restricted earth-fault protection, low impedance function REFPDIF has
inputs to allow two current inputs from each side of the transformer. The second
winding set is only applicable for autotransformers.
A typical connection for a star-delta transformer is shown in figure
76.
1MRK 502 071-UEN - Section 7
Differential protection
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062 179
Application manual