Technical Data
4.3 Differential Protection
SIPROTEC, 7SD5, Manual
C53000-G1176-C169-5, Release date 02.2011
588
4.3
Differential Protection
Pickup Values
Intertrippings
Differential current,
I-DIFF>
I
N
= 1 A
0.10 A to 20.00 A
Increments 0.01 A
I
N
= 5 A
0.50 A to 100.00 A
Differential current when switching onto a
fault;
I-DIF>SWITCH ON
I
N
= 1 A
0.10 A to 20.00 A
Increments 0.01 A
I
N
= 5 A
0.50 A to 100.00 A
Differential current, high set differential
current
I-DIFF>>
I
N
= 1 A
0.80 A to 100.00 A
or
∞
(stage disabled)
Increments 0.01 A
I
N
= 5 A
4.00 A to 500.00 A
or
∞
(stage disabled)
Differential current, high set differential
current when
switching onto a fault; I-DIF>>SWITCHON
I
N
= 1 A
0.80 A to 100.00 A
or
∞
(stage inactive)
Increments 0.01 A
I
N
= 5 A
4.00 A to 500.00 A
or
∞
(stage inactive)
Tolerances
For 2 or 3 ends
5 % of setting value or 1% I
N
per end
For 6 ends
10 % of setting value or 1% I
N
per end
The operating times depend on the number of ends and the communication speed. The following data require a transfer
rate of 512 kbit/s and the output of commands via high-speed output relays (7SD5***-*N/P/Q/R/S/T).
Pickup / trip times of the
I
-DIFF>> stages at 50 or 60 Hz approx.
for 2 ends
minimum
9 ms
typical
12 ms
for 3 ends
minimum
9 ms
typical
12 ms
for 6 ends
minimum
14 ms
typical
20 ms
Dropout times of the I-DIFF>> stages approx.
or all ends
typical
35 ms to 50 ms
Pickup / tripping times of the I-DIFF> stages approx.
for 2 ends
minimum (50 Hz / 60 Hz)
27 ms / 24 ms
typical (50 Hz / 60 Hz)
29 ms / 26 ms
for 3 ends
minimum (50 Hz / 60 Hz)
27 ms / 24 ms
typical (50 Hz / 60 Hz)
31 ms / 28 ms
for 6 ends
minimum (50 Hz / 60 Hz)
32 ms / 28 ms
typical (50 Hz / 60 Hz)
38 ms / 35 ms
Dropout times of the I-DIFF> stages approx.
for all ends
typical
35 ms to 50 ms