7SR11 & 7SR12 Performance Specification
ยฉ2017 Siemens Protection Devices Limited Chapter 3 Page 38 of 56
Attribute Value
IEC DECAYING
, ยฑ 5 % absolute or ยฑ 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
t
res
, ยฑ 1 % or ยฑ 20ms
Repeatability
ยฑ 1 % or ยฑ 20ms
Overshoot time < 40 ms
Disengaging time < 50 ms
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.