VAMP 265 - Page 55

Technical description
2 Protection functions
2.4 Differential overcurrent
protection ΔI> (87)
VM265.EN011
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Parameters of the differential overcurrent stages I> (87):
Parameter
Value/unit
Measured
values (1
L1
L2
L3
xIn
Current difference value
Setting
values (2
I>
%ln
Setting value
Slope1
%
Slope 1 setting
Ibias2
xIn
Bias current start of slope 2
Slope2
%
Slope 2 setting
Harm2>
On/Off
2. harmonic blocking
enable/disable
Harm2>
%
2. harmonic block limit
TCntr
Cumulative trip counter
Type
1-N, 2-N,
3-N
Fault type/single-phase fault e.g.:
1-N = fault on phase L1
1-2, 2-3,
1-3
Fault type/two-phase fault e.g.: 2-3
= fault between L2 and L3
1-2-3
Fault type/three-phase fault
Flt
xIn
Max. value of fault differential
current as compared to I
n
Bias
xIn
Value of bias current of faulted
phase as compared to I
n
Load
xIn
1 s mean value of pre-fault phase
currents IL1…IL3
1) Measurement ranges are described in section 9.1.1.
2) Setting ranges are described in section 9.3.2.
Parameters of the differential overcurrent stages I>> (87):
Parameter
Value/unit
Measured
values
L1
L2
L3
xIn
Current difference value
Setting
values
I>>
xIn
Setting value
Recorded
values
TCntr
Cumulative trip counter
Type
1-N, 2-N,
3-N
Fault type/single-phase fault e.g.:
1-N = fault on phase L1
1-2, 2-3,
1-3
Fault type/two-phase fault e.g.: 2-3
= fault between L2 and L3
1-2-3
Fault type/three-phase fault
Flt
xIn
Max. value of fault differential
current as compared to I
n
Load
xIn
1 s mean value of pre-fault phase
currents IL1…IL3