ISA T1000 PLUS - Page 70

DOC. MIE91093 Rev. 1.34 Page 70 of 145
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Resistance
Reactance
Relay Characteristic
Generator Working Point
The relay detect the loss of field fault when the working point
enters the relay characteristic curve (the circle). The typical
parameters for LOF relays are the following.
K1 : circle diameter; expressed in % of ZN;
K2: offsert; expressed in % of ZN;
3*IN
VN
ZN 
K2
K1
R
X