ABB REG670 - Autotransformer Winding, Solidly Earthed

7.4.2.3 Autotransformer winding, solidly earthed
Autotransformers can be protected with the low impedance restricted earth-fault
protection function REFPDIF. The complete transformer will then be protected
including the HV side, the neutral connection and the LV side. The connection of
REFPDIF for this application is shown in figure
74.
IEC09000111-4-EN.vsd
Auto
-
transformer
REFPDIF
I3PW1CT1
I3P
IdN/I
I3PW2CT1
HV (W1)
LV (W2)
IEC09000111-4-EN V2 EN
Figure 74: Connection of restricted earth fault, low impedance function
REFPDIF for an autotransformer, solidly earthed
7.4.2.4 Reactor winding, solidly earthed
Reactors can be protected with restricted earth-fault protection, low impedance
function REFPDIF. The connection of REFPDIF for this application is shown in
figure 75.
Section 7 1MRK 502 071-UEN -
Differential protection
178 Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Application manual