GE 845 Instruction Manual page 287

CHAPTER 4: SETPOINTS
MULTIPLIER CURRENT (I/I
(TDM)
1.5
10.0 11.552
IAC SHORT INVERSE
0.5 0.072
1.0 0.143
2.0 0.286
4.0 0.573
6.0 0.859
8.0 1.145
10.0 1.431
2
Table 4-32: I T CURVE TRIP TIMES (IN SECONDS)
MULTIPLIER CURRENT (I/I
(TDM)
1.5
0.01 0.44
0.10 4.44
1.00 44.44
10.00 444.44
100.00 4444.44
600.00 26666.7
845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
)
pickup
2.0 3.0 4.0
7.494 5.320 4.426
0.047 0.035 0.031
0.095 0.070 0.061
0.190 0.140 0.123
0.379 0.279 0.245
0.569 0.419 0.368
0.759 0.559 0.490
0.948 0.699 0.613
2
I T CURVES
2
The curves for the I t are derived from the formula:
Where:
T = operate time (in seconds)
TDM = Multiplier setting
I = input current
I = Pickup Current setting
pickup
T = reset time in seconds (assuming energy capacity is 100% and RESET is
RESET
"Timed")
)
pickup
2.0 3.0 4.0
0.25 0.11 0.06
2.50 1.11 0.63
25.00 11.11 6.25
250.00 111.11 62.50
2500.00 1111.1 625.00
15000.0 6666.7 3750.0
4
I T CURVES
4
The curves for the I t are derived from the formula:
Where:
T = operate time (in seconds)
TDM = Multiplier setting
I = input current
I = Pickup Current setting
pickup
5.0 6.0 7.0
3.922 3.597 3.369
0.028 0.027 0.026
0.057 0.054 0.052
0.114 0.108 0.105
0.228 0.217 0.210
0.341 0.325 0.314
0.455 0.434 0.419
0.569 0.542 0.524
5.0 6.0 7.0
0.04 0.03 0.02
0.40 0.28 0.20
4.00 2.78 2.04
40.00 27.78 20.41
400.00 277.78 204.08
2400.0 1666.7 1224.5
PROTECTION
8.0 9.0 10.0
3.201 3.072 2.969
0.026 0.025 0.025
0.051 0.050 0.049
0.102 0.100 0.099
0.204 0.200 0.197
0.307 0.301 0.296
0.409 0.401 0.394
0.511 0.501 0.493
8.0 9.0 10.0
0.02 0.01 0.01
0.16 0.12 0.10
1.56 1.23 1.00
15.63 123.5 10.00
156.25 123.46 100.00
937.50 740.74 600.00
4–159