ABB RELION RET670 - Transformer Winding, Grounded through Zig-Zag Grounding Transformer

REFPDIF (87N)
I3P
I3PW1CT1
ANSI05000210_3_en.vsd
ANSI05000210 V3 EN-US
Figure 62: Connection of the low impedance Restricted earth fault function
REFPDIF (87N) for a directly (solidly) grounded transformer winding
7.3.2.2 Transformer winding, grounded through Zig-Zag grounding transformer
M13048-8 v10
A common application is for low reactance grounded transformer where the grounding
is through separate Zig-Zag grounding transformers. The fault current is then limited to
typical 800 to 2000 A for each transformer. The connection for this application is
shown in figure
63.
Section 7 1MRK 504 163-UUS A
Differential protection
178 Transformer protection RET670 2.2 ANSI
Application manual