Technical Data
4.3 Differential Protection
SIPROTEC, 7SD5, Manual
C53000-G1176-C169-5, Release date 02.2011
589
Delay times
Self-restraint
Inrush restraint
Conditioning for transformers (optional)
Emergency operation
Frequency operating range
Standard precision of operational measured values
Delay of
I
-DIFF stage
T-DELAY I-DIFF>
0.00 s to 60.00 s
or
∞
(no trip)
Increments 0.01 s
Delay of
I
-DIFF stage
for 1-phase pickup in isolated / compensated net-
works
T3I0 1PHAS
0.00 s to 0.50 s
or
∞
(stage disabled for
1-phase pickup)
Increments 0.01 s
Expiry tolerances
1 % of set value or 10 ms
The set times are pure delay times.
Current transformer error at each end of the protected object
Ratio between operating accuracy limit factor
and nominal accuracy limit factor n'/n
1.00 to 10.00
Increments 0.01
Transformer error at n'/n
0.5 % to 50.0 %
Increments 0.1 %
Transformer error at n
.
I
N
(class)
0.5 % to 50.0 %
Increments 0.1 %
Further restraint quantities
(adaptive self-restraint)
Frequency deviations, delay time differences,
harmonics, synchronous quality, jitter
Restraint ratio
2nd harmonics to the fundamental
I
2fN
/
I
fN
0 % to 45 %
Increments 1 %
Max. current for restraint
I
N
= 1 A
1.1 A to 25.0 A
Increments 0.1 A
I
N
= 5 A
5.5 A to 125.0 A
Crossblock Function
can be switched on/off
Max. action time for crossblock CROSSB 2HM
0.00 s to 60.00 s
or 0 (crossblock disabled)
or
∞
(active until dropout)
Increments 0.01 s
Vector group matching
0 to 11 (x 30°)
Increments 1
Star-point conditioning
earthed or non-earthed (for each winding)
If the communication fails and the distance protection is disabled
See Section „Time Overcurrent Protection“
Frequency
0.8
≤
f/f
N
≤
1.2 stable when starting machine
The standard precision of the operational measured values of the differential protection from
±
0.5% of the rated opera-
tional current is ensured up to a transformer error adjustment of 2:1.
