ABB REC 561 - Page 10

Introduction - REC 561
ABB Network Partner AB
1MRK 580 146-XEN
Page 2 - 5
Version 1.0-00
are needed, then external transducers connected to mA inputs in REC 561
can be used. To get the line current, the currents through the circuit break-
ers are summed externally.
The synchro-check function is applicable only for one diameter. By using
REC 561 type 3, one more diameter can be added including control and
interlocking functions, but then external synchro-check functions are
needed. Control of all earthing switches within the two diameters are lim-
ited, because the upper limit of the number of apparatuses to be controlled
is still 24.
Fig. 3 Breaker-and-a-half arrangement
Three single-breaker bays
REC 561 type 2 is normally used for this application. The maximum
number of single-breaker bays including synchro-check functions are
three. Of course one of the bays can be a bus-coupler bay. The voltages to
be used for the synchro-check function are based on one-phase values. If
P, Q, f, and three-phase values of U and I are needed, then external trans-
ducers connected to mA inputs in REC 561 can be used.
Fig. 4 Three, single-breaker arrangement
REC
561
1 U
1 U
1 U
1 U
1 I
1 I
(X80146-3)
1 U
1 U
1 U
REC
561
1 U
1 U
(X80146-4)