ABB Relion 670 series - Page 147

ANSI05000427-2-en.vsd
I>
R
Rres
Rl
Rct Rct
Rl
VR
a) Through load situation
b) Through fault situation
VR
VR
c) Internal faults
VR
Protected Object
ANSI05000427 V2 EN
Figure 50: The high impedance principle for one phase with two current transformer
inputs
1MRK 506 369-UUS - Section 7
Differential protection
Line distance protection REL670 2.2 ANSI 141
Application manual