Restricted Earth Fault Protection - Siemens SIPROTEC 7SD610 Manual

Technical Data

4.4 Restricted Earth Fault Protection

4.4 Restricted Earth Fault Protection
Setting ranges
Differential current I >
REF
Threshold angle ϕ
Limit
Trip Characteristic
Pickup tolerance for ϕ(3I
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.
Drop-off to pickup ratio
Figure 4-1
340
for I
for I
", 3I ') < 90°
0 0
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
= 1 A 0.05 A to 2.00 A
N
= 5 A 0.25 A to 10.00 A
N
100° (fixed)
see Figure below
5 % ± 0.01 · I
N
0.00 s to 60.00 s
or ∞ (no trip)
1 % of set value or 10 ms
50 Hz
35 ms
35 ms
30 ms
Approx. 0.7
C53000-G1176-C145-6, Release date 02.2011
Increment 0.01
Increments 0.01 s
60 Hz
34 ms
34 ms
30 ms
> = setting; I = tripping
REF REF
SIPROTEC, 7SD610, Manual