Table of Contents
Advertisement
Technical Data
4.4 Restricted Earth Fault Protection
4.4
Restricted Earth Fault Protection
Setting ranges
Differential Current I
>
EDS
Threshold angle ϕ
EDS
Trip characteristic
Pick-up tolerance
o
for ϕ (3I
", 3I
') < 90
0
0
and address 221 I4/Iph CT =
and address 4113 SLOPE =
Delay time T
EDS
Expiry tolerances
The set times are pure delay times
Operating Time
Pickup time at frequency
at 1.5 · set value I
> approx.
REF
at 2.5 · set value I
> approx.
REF
Dropout time, approx.
Dropout ratio
Figure 4-1
590
for I
= 1 A
N
for I
= 5 A
N
Tripping characteristic of the restricted earth fault protection depending on the earth current
ratio 3I
"/3I
' (both currents in phase + or counter-phase –); I
0
0
current
0.05 A to 2.00 A
0.25 A to 10.00 A
100° (fixed)
see Figure below
5 % plus ± 0.01 · I
N
0.00 s to 60.00 s
or ∞ (no trip)
1 % of set value or 10 ms
high-speed relays
high-speed relays
high-speed relays
high-speed relays
Increment 0.01 A
Increments 0.01 s
50 Hz
60 Hz
35 ms
34 ms
30 ms
29 ms
35 ms
34 ms
30 ms
29 ms
30 ms
30 ms
Approx. 0.7
> = setting; I
REF
REF
SIPROTEC, 7SD5, Manual
C53000-G1176-C169-5, Release date 02.2011
= tripping
Advertisement
Table of Contents
