Woodward
Technical Manual WIC1
20
DOK-TD-WIC1E, Rev. L
5.1.2 Phase time over current protection
The following setting ranges and gradings apply for WIC1-1 and WIC1-4 devices. Here the parameters can only be
set via a serial interface.
Current
Arithmetic averages measurement
Threshold values
I>
0.9 to 2.5 x IS in steps of 0.05 x I
S
when adjusting via interface
I>>
1 to 20 x IS in steps of 0.1 x I
S
when adjusting via interface
Tripping time for the definite
time over current element
tI>
0.04s to 300s in the following steps when adjusting via
interface
0.04s - 1s in 0.01 s steps
1s - 5s in 0.1s steps
5s - 20s in 0.5s steps
20s - 100s in 2s steps
100s - 300s in 5s steps
IMT characteristics*:
Normal Inverse (N-INV)
Very Inverse (V-INV)
Extremely Inverse (E-INV)
Long Time Inverse (L-INV)
RI-Inverse (RI-INV)
Fuse characteristic of a HV fuse
Fuse characteristic of a full range fuse (FR-Fuse)
Time factor
0.05 to 10 in steps of 0.05 when adjusting via interface
Tripping times for the definite
time short-circuit element
tI>>
0.04s to 3s in the following steps when adjusting via interface
0.04s - 1s in 0.01 s steps
1s - 3s in 0.02 s steps
The min. tripping time when switched on to a failure is subject to the fault current level. See
the following diagram. The diagram shows the tripping time under worst conditions like
ageing, temperature.
Im = Minimum current (chapter 4.1.1)
With the WIC1 protection system minimal tripping times of 40 ms can be achieved.
Time correction
of current 0
≤ 45ms
of current > Im
≥ 35ms
Disengaging time
< 30ms
* The starting point of the characteristic should be in the area of the rated CT current , e. g. W2 = 16
– 56 A. If over the parameter I> the starting
point is set higher, then the relay cut the characteristics at 20 x upper rated current.
Minimale Auslösezeiten
Minimum tripping times
10
100
1000
0
5
10
15
20
t [
m
s]
einphasige
Speisung /
single phase
supply
zweiphasige
Speisung /
dual phase
supply
dreiphasige
Speisung /
three phase
supply
Im
I