Siemens 7SR12 Argus - Page 154

7SR11 & 7SR12 Performance Specification
©2017 Siemens Protection Devices Limited Chapter 3 Page 42 of 56
Attribute Value
char = DTL
t
d
, ± 1 % or ± t
cycle
Reset time
char = ANSI and
t
res
= DECAYING
[ ]
Tm
R
t
Is
I
res
×
−
=
1
2
, ± 5 % absolute or ± 30 ms,
for char = ANSI-MI : R = 4.85
ANSI-VI : R = 21.6
ANSI-EI : R = 29.1
IEC DECAYING
[ ]
Tm
R
t
Is
I
res
×
−
=
1
2
, ± 5 % absolute or ± 50 ms,
for char = IEC-NI : R = 9.7
IEC-VI : R = 43.2
IEC-EI : R = 58.2
IEC-LTI : R = 80
t
res
≠ DECAYING t
res
, ± 1 % or ± 20ms
Repeatability
± 1 % or ± 20ms
Overshoot time < 40 ms
Disengaging time < 50 ms
Variation
f
nom
± 5 %
harmonics to f
cutoff
≤ 5 %
Figure 2.12-1and Figure 2.12-4 show the operate and reset curves for the four IEC IDMTL curves with a time
multiplier of 1.
Figure 2.12-2 and Figure 2.12-3 show the ANSI operate and reset curves. These operate times apply to non-
directional characteristics. Where directional control is applied then the directional element operate time should be
added to give total maximum operating time.