Siemens Argus 7SR21 Technical Manual page 349

2.14.3
Operate and Reset Time
Attribute
Starter operate time (³ 2xIs)
t Operate time
op
Reset time
Repeatability
Overshoot time
Disengaging time
Figure 2.2 shows the operate times for the four IEC IDMTL curves with a time multiplier of 1. Figure 2.3 and
Figure 2.4 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.
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char = IEC-NI,
IEC-VI,
IEC-EI,
IEC-LTI
char = ANSI-MI,
ANSI-VI,
ANSI-EI
char = DTL
ANSI DECAYING
t
res
7SR21 & 7SR22 Performance Specification
Value
20 ms, ± 20 ms
K
= ´
t Tm , ± 5 % or ± 30 ms,
[ ]
op
a
I -
1
Is
IEC-NI : K = 0.14, a = 0.02
for char =
IEC-VI : K = 13.5, a = 1.0
IEC-EI : K = 80.0, a = 2.0
IEC-LTI : K = 120.0, a = 1.0
é ù
A
ê ú
= + ´
t B Tm
[ ]
op
ê ú
P
I -
1
ë û
Is
for char = ANSI-MI : A = 0.0515, B = 0.114, P = 0.02
ANSI-VI : A = 19.61, B = 0.491, P = 2.0
ANSI-EI : A = 28.2,
, ± 1 % or ± 20ms
t
d
R
= ´
t Tm
, ± 5 % or ± 30 ms,
[ ]
res
2
-
I 1
Is
for char = ANSI-MI : R = 4.85
ANSI-VI : R = 21.6
ANSI-EI : R = 29.1
, ± 1 % or ± 20 ms
t
res
± 1 % or ± 20 ms
< 40 ms
< 50 ms
, ± 5 % or ± 30 ms,
B = 0.1217, P = 2.0
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