Operate And Reset Time - Siemens 7SR224 Technical Manual

2.10.3 Operate and Reset Time

Attribute
Starter operate time (≥ 2xIs)
char = IEC-NI,
Operate time
t
op
char = ANSI-MI,
char = DTL
ANSI DECAYING
Reset time
t
res
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 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.
©2010 Siemens Protection Devices Limited
Value
20 ms, ± 20ms
K
=
t
[ ]
op α
I
Is
IEC-VI,
for char =
IEC-EI,
IEC-LTI
⎡
⎢
=
t [ ]
⎢
op
I
ANSI-VI,
⎣
Is
ANSI-EI
for char = ANSI-MI : A = 0.0515, B = 0.114, P = 0.02
, ± 1 % or ± 20ms
t
d
=
t
[ ]
res
I
Is
for char = ANSI-MI : R = 4.85
, ± 1 % or ± 20ms
t
res
± 1 % or ± 20ms
< 40 ms
< 50 ms
7SR224 Argus Performance Specification
×
, ± 5 % absolute or ± 30 ms,
Tm
−
1
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
⎤
A
⎥
+ ×
, ± 5 % absolute or ± 30 ms,
B Tm
⎥
P
−
1
⎦
ANSI-VI : A = 19.61, B = 0.491, P = 2.0
ANSI-EI : A = 28.2, B = 0.1217, P = 2.0
R
×
, ± 5 % absolute or ± 30 ms,
Tm
−
2
1
ANSI-VI : R = 21.6
ANSI-EI : R = 29.1
Chapter 3 Page 29 of 49