Thermal Overload; Reference; Operate And Reset Level; Operate And Reset Time - Siemens 7SR10 Argus Series Manual

2.7

49 Thermal Overload

2.7.1

Reference

Parameter
Iθ Overload setting
Time constant setting
τ
i Applied Current (for operate time)
2.7.2

Operate and Reset Level

Attribute
I Overload level
ol
Reset level
Repeatability
Variation
2.7.3

Operate and Reset Time

Attribute
t Overload trip operate time
op
Repeatability
Note:- Fastest operate time is at 10xI
© 2018 Siemens Protection Devices Limited
-10 °C to +60 °C
f ± 5 %
nom
s
Value
0.1...to 3.0xI
n
1, 10, 100, 1000 min
1.2 to 10xI
s
Value
100 % I , ± 5 % or ± 1 % I
s
≥ 95 % I
op
± 1 %
≤ 5 %
≤ 5 %
Value
 
2 2
I − I
t = τ × ln P
 
( )
2
2 k I
I − ×
 
B
where I = prior current
P
± 100 ms
7SR10 Performance Specification
n
± 5 % absolute or ± 100 ms,
(Is: 0.3 – 3xI )
n
Chapter 3 Page 22 of 52