Siemens 7SR224 - Operate and Reset Time

7SR224 Argus Performance Specification
©2010 Siemens Protection Devices Limited Chapter 3 Page 27 of 49
2.9.3 Operate and Reset Time
Attribute Value
Starter operate time (≥ 2xIs) 20 ms, ± 20ms
char = IEC-NI,
IEC-VI,
IEC-EI,
IEC-LTI
[]
Tm
K
t
Is
I
op
×
−
=
1
α
, ± 5 % absolute or ± 30 ms,
for char = IEC-NI : K = 0.14, α = 0.02
IEC-VI : K = 13.5, α = 1.0
IEC-EI : K = 80.0, α = 2.0
IEC-LTI : K = 120.0, α = 1.0
char = ANSI-MI,
ANSI-VI,
ANSI-EI
[]
TmB
A
t
P
Is
I
op
×
⎥
⎥
⎦
⎤
⎢
⎢
⎣
⎡
+
−
=
1
, ± 5 % absolute or ± 30 ms,
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, B = 0.1217, P = 2.0
t
op
Operate time
char = DTL
t
d
, ± 1 % or ± 20ms
ANSI 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
Reset time
t
res
t
res
, ± 1 % or ± 20ms
Repeatability
± 1 % or ± 20ms
Overshoot time < 40 ms
Disengaging time < 50 ms
Figure 2-2 shows the operate times for the four IEC IDMTL curves with a time multiplier of 1.
Figure 2-3 shows the ANSI IDMTL Operate Curves (Time Multiplier=1) and Figure 2-4 shows the ANSI Reset
Curves (Time Multiplier = 1). 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.