Siemens siprotec SJ62, User Manual

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4.3 Inverse Time Overcurrent Protection 51, 51N
462
SIPROTEC 4, 7SJ62/63/64 Handbuch
C53000-G1140-C147-A, Edition 07.2015
Dropout Time Characteristics with Disk Emulation acc. to IEC
Dropout Setting
Tolerances
Influencing Variables for Pickup and Dropout
Ass. to IEC 60255-3 or BS 142, Section 3.5.2 (see also Figures 4-1 and 4-2)
The dropout time curves apply for the range 0.05
≤
( I / I p)
≤
0.90
For zero-sequence current read 3 I 0p instead of I
p
and T
3
I
0p
instead of T
p
;
for ground fault read
I
Ep
instead of
I
p
and T
I Ep
instead of T
p
IEC without Disk Emulation approx. 1.05 · set value
I
p
for
I
p
/
I
Nom
≥
0.3,
corresponds to approx. 0.95 · pickup threshold
IEC with Disk Emulation approx. 0.90 · set value I
p
Pickup/dropout thresholds I
p
, I
Ep
2 % of set value or 10 mA for I
Nom
= 1 A
or 50 mA for
I
Nom
= 5 A
Pickup time for 2
≤
I
/
I
p
≤
20 5 % of reference (calculated) value + 2 %
current tolerance, respectively 30 ms
Dropout ratio for I / I
p
≤
0.90 5 % of reference (calculated) value + 2 %
current tolerance, respectively 30 ms
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 0.95
≤
f/f
Nom
≤
1.05 1 %