Siemens SIPROTEC 4 7SJ61 - Page 297

The dropout time curves apply to (Ι/Ιp) ≤ 0.90
For zero sequence current read 3Ι0p instead of Ι
p
and T
3Ι0p
instead of T
p
;
for ground fault read Ι
Ep
instead of Ι
p
and T
ΙEp
instead of T
p
Dropout Setting
ANSI without Disk Emulation
approx. 1.05 · setting value Ι
p
for Ι
p
/Ι
N
≥ 0.3; corresponds to approx.
0.95 · pickup value
Reset of the Integration Timer
ANSI with Disk Emulation
approx. 0.90 · setting value Ι
p
Tolerances
Pickup/dropout thresholds
Ι
p
, Ι
Ep
2% of setting value or 10 mA for Ι
Nom
= 1 A or 50 mA for Ι
Nom
= 5 A
Trip time for 2 ≤ Ι/Ι
p
≤ 20
5 % of reference (calculated) value + 2 % current tolerance, or 30 ms
Dropout time forΙ/Ι
p
≤ 0.90
5 % of reference value + 2 %, or 30 ms
Influencing Variables for Pickup and Dropout
Power supply direct voltage in range 0.8 ≤ V
PS
/V
PSNom
≤ 1,15 1 %
Temperature in range 23.00 °F (-5 °C) ≤ Θ
amb
≤ 131.00 °F (55 °C) 0.5 %/10 K
Frequency in range 25 Hz to 70 Hz 1 %
Technical Data
4.3 Inverse-time Overcurrent Protection
SIPROTEC 4, 7SJ61, Manual 297
C53000-G1140-C210-6, Edition 05.2016