7SR21 & 7SR22 Performance Specification
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2.9 49 Thermal Overload
2.9.1 Reference
Parameter Value
Is Overload setting 0.10, 0.11… 3 xIn
t
Time constant setting 1, 1.5… 1000 min
2.9.2 Operate and Reset Level
Attribute Value
I
ol
Overload level
100 % Is, ± 5 % or ± 1% In
Reset level
³ 95 % I
ol
Repeatability
± 1 %
Variation
-10 °C to +55 °C
£ 5 %
f
nom
- 3 Hz to f
nom
+ 2 Hz
£ 5 %
2.9.3 Operate and Reset Time
Attribute Value
t
op
Overload trip operate time
( )
þ
ý
ü
î
í
ì
´-
-
´t=
2
2
2
P
2
I
II
ln
B
Ik
t
where I
P
= prior current
± 5 % o r ± 1 0 0 m s ,
(For I
s
range 0.3 xI
n
to 3 xI
n
)
Repeatability
± 100 ms
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