CHAPTER 5: SETTINGS
GROUPED ELEMENTS
M60 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
5-259
5
I
2
t curves
The I
2
t curves are derived as follows:
Eq. 5-43
where
T = Operate time (in seconds)
TDM = Multiplier setting
I = Input current
I
pickup
= Pickup Current setting
T
RESET
= reset time in seconds (assuming energy capacity is 100% and RESET is “Timed”)
Table 5-43: I
2
t curve trip times
FlexCurves
FlexCurves are described in the FlexCurves section later in this chapter. The curve shapes for the FlexCurves are derived
from the formulae:
Eq. 5-44
Eq. 5-45
where
T = operate time (in seconds)
TDM = Multiplier setting
I = Input Current
I
pickup
= Pickup Current setting
T
RESET
= Reset Time in seconds (assuming energy capacity is 100% and
RESET
: Timed)
10.0
1.431
0.948
0.699
0.613
0.569
0.542
0.524
0.511
0.501
0.493
Multiplier
(TDM)
Current ( I / I
pickup
)
1.5
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
0.01
0.44
0.25
0.11
0.06
0.04
0.03
0.02
0.02
0.01
0.01
0.10
4.44
2.50
1.11
0.63
0.40
0.28
0.20
0.16
0.12
0.10
1.00
44.44
25.00
11.11
6.25
4.00
2.78
2.04
1.56
1.23
1.00
10.00
444.44
250.00
111.11
62.50
40.00
27.78
20.41
15.63
12.35
10.00
100.00
4444.4
2500.0
1111.1
625.00
400.00
277.78
204.08
156.25
123.46
100.00
600.00
26666.7
15000.0
6666.7
3750.0
2400.0
1666.7
1224.5
937.50
740.74
600.00
Multiplier
(TDM)
Current ( I / I
pickup
)
1.5
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
Summary of Contents for M60
Page 9: ...TABLE OF CONTENTS M60 MOTOR PROTECTION SYSTEM INSTRUCTION MANUAL ix INDEX ...
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Page 552: ...5 344 M60 MOTOR PROTECTION SYSTEM INSTRUCTION MANUAL TESTING CHAPTER 5 SETTINGS 5 ...
Page 660: ...iv M60 MOTOR PROTECTION SYSTEM INSTRUCTION MANUAL ABBREVIATIONS ...