Instruction manual
M-LIB3 Low Impedance Bus Differential Relay
24
To compensate the differential current produced by CT’s error or saturation, the actual minimum operation
level I
S
is dynamically adjusted in function of the actual through current I
R
according to the set coefficient [1R],
[2R]
• I
R
< [1I
R
] : I
S
= I
dS
‚ [1I
R
] < I
R
< [2I
R
] : I
S
= I
dS
+ 1R(I
R
-[1I
R
])
ƒ I
R
> [2I
R
] : I
S
= I
dS
+ 1R([2I
R
]-[1I
R
]) + 2R(I
R
-[2I
R
])
„ BIAS SATURATION : I
S
= 10 In for any I
R
[2I]
R
∆
IR
[I/In]
ds
∆
IR
∆
Ids
R=
[2R]
∆
Ids
I/InR
[1I]R
‚
ƒ
„
•
[1R]
Is/In
∆
Ids