Siemens 7SR18 Solkor - Differential; Reference; Operate and Reset Level; Operate Time

7SR18 Performance Specification
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of
2.11 87L Differential
2.11.1 Reference
Parameter Value
Initial Setting 0.1, 0.15 … 2.5 xIn
1
st
Bias Slope 0.1, 0.15 … 0.7 x
1
st
Bias Slope Limit 0.5, 0.6 … 20 xIn
2
nd
Bias Slope 0.5, 0.55 … 2 x
Delay setting 0, 0.005 … 60 s
2.11.2 Operate and Reset Level
Attribute Value
I
OP
Operate level
2
nd
Bias Slope
B)I(forIMI
andIMI
andII
RESTRAINRESTRAIN2OPERATE
RESTRAIN1OPERATE
SETTINGINITIAL87OPERATE
>×>
×>
>
Where: -
I
operate
= 

+ 

I
restrain
=


+

2
B = 87BD 1
st
Bias slope limit
M
1
= 87BD 1
st
Bias slope
M
2
= 87BD 2
nd
Bias slope
Operate Level
± 10 % of I
OP
or ± 0.1In
Reset level ≥ 90 % of I
OP
Repeatability
± 2 %
Transient overreach ≤ 5 %
Variation
-10 °C to +55 °C
f
nom
- 3 Hz to f
nom
+ 2 Hz
2.11.1 Operate Time
Attribute Value (Typical)
t
Op
Element operate time (fault line)
30 ms ± 5 ms (fault line)
50 ms ± 5 ms (below fault line)