ABB REF 543 - Page 56

Feeder Terminal REF 541, REF 543, REF 545.
1MRS750443-MBG
56
Fig. 9 An REF 54_ feeder terminal used for the protection, control, measurement and supervision func-
tions of a utility feeder (main single-line diagram presentation). The neutral point of the supplying
network is isolated. The scheme is also fully applicable in high-impedance earthed networks,
where the neutral point is earthed via a high resistance or a Petersen coil.
M
M
MF
3I > 50/51
I
0-0
>
51N
3I
2f
>
68
I
0
> 67N
CBFP * /62
0
I
79
f <
81U
DI>
46
MCS
R
I
0
P
E
CBCM
TCS
000
0
I
3I
3U
EXFDR1
REF 54_