5-196 M60 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
GROUPED ELEMENTS CHAPTER 5: SETTINGS
5
Table 5-24: Curve multipliers
If “IEC” is selected as the thermal model curve, the M60 can apply the IEC 255-8 hot and cold curve characteristics to the
thermal model. The M60 evaluates the thermal capacity at motor start and chooses the appropriate curve. The hot curve
characteristic is applied when the thermal capacity is greater than or equal to 5% (that is, a point above where the motor
is not at complete rest, or cold). Otherwise, the cold curve characteristic is applied.
The IEC255-8 cold curve trip time is defined as follows:
Eq. 5-8
The IEC255-8 hot curve trip time is defined as follows:
Eq. 5-9
where
Pickup
level
M60 standard curve multipliers
x1 x2 x3 x4 x5 x6 x7 x8 x9 x10 x11 x12 x13 x14 x15
1.01 4353.6 8707.2 13061 17414 21768 26122 30475 34829 39183 43536 47890 52243 56597 60951 65304
1.05 853.71 1707.4 2561.1 3414.9 4268.6 5122.3 5976.0 6829.7 7683.4 8537.1 9390.8 10245 11098 11952 12806
1.10 416.68 833.36 1250.0 1666.7 2083.4 2500.1 2916.8 3333.5 3750.1 4166.8 4583.5 5000.2 5416.9 5833.6 6250.2
1.20 198.86 397.72 596.58 795.44 994.30 1193.2 1392.0 1590.9 1789.7 1988.6 2187.5 2386.3 2585.2 2784.1 2982.9
1.30 126.80 253.61 380.41 507.22 634.02 760.82 887.63 1014.4 1141.2 1268.0 1394.8 1521.6 1648.5 1775.3 1902.1
1.40 91.14 182.27 273.41 364.55 455.68 546.82 637.96 729.09 820.23 911.37 1002.5 1093.6 1184.8 1275.9 1367.0
1.50 69.99 139.98 209.97 279.96 349.95 419.94 489.93 559.92 629.91 699.90 769.89 839.88 909.87 979.86 1049.9
1.75 42.41 84.83 127.24 169.66 212.07 254.49 296.90 339.32 381.73 424.15 466.56 508.98 551.39 593.81 636.22
2.00 29.16 58.32 87.47 116.63 145.79 174.95 204.11 233.26 262.42 291.58 320.74 349.90 379.05 408.21 437.37
2.25 21.53 43.06 64.59 86.12 107.65 129.18 150.72 172.25 193.78 215.31 236.84 258.37 279.90 301.43 322.96
2.50 16.66 33.32 49.98 66.64 83.30 99.96 116.62 133.28 149.94 166.60 183.26 199.92 216.58 233.24 249.90
2.75 13.33 26.65 39.98 53.31 66.64 79.96 93.29 106.62 119.95 133.27 146.60 159.93 173.25 186.58 199.91
3.00 10.93 21.86 32.80 43.73 54.66 65.59 76.52 87.46 98.39 109.32 120.25 131.19 142.12 153.05 163.98
3.25 9.15 18.29 27.44 36.58 45.73 54.87 64.02 73.16 82.31 91.46 100.60 109.75 118.89 128.04 137.18
3.50 7.77 15.55 23.32 31.09 38.87 46.64 54.41 62.19 69.96 77.73 85.51 93.28 101.05 108.83 116.60
3.75 6.69 13.39 20.08 26.78 33.47 40.17 46.86 53.56 60.25 66.95 73.64 80.34 87.03 93.73 100.42
4.00 5.83 11.66 17.49 23.32 29.15 34.98 40.81 46.64 52.47 58.30 64.13 69.96 75.79 81.62 87.45
4.25 5.12 10.25 15.37 20.50 25.62 30.75 35.87 41.00 46.12 51.25 56.37 61.50 66.62 71.75 76.87
4.50 4.54 9.08 13.63 18.17 22.71 27.25 31.80 36.34 40.88 45.42 49.97 54.51 59.05 63.59 68.14
4.75 4.06 8.11 12.17 16.22 20.28 24.33 28.39 32.44 36.50 40.55 44.61 48.66 52.72 56.77 60.83
5.00 3.64 7.29 10.93 14.57 18.22 21.86 25.50 29.15 32.79 36.43 40.08 43.72 47.36 51.01 54.65
5.50 2.99 5.98 8.97 11.96 14.95 17.94 20.93 23.91 26.90 29.89 32.88 35.87 38.86 41.85 44.84
6.00 2.50 5.00 7.49 9.99 12.49 14.99 17.49 19.99 22.48 24.98 27.48 29.98 32.48 34.97 37.47
6.50 2.12 4.24 6.36 8.48 10.60 12.72 14.84 16.96 19.08 21.20 23.32 25.44 27.55 29.67 31.79
7.00 1.82 3.64 5.46 7.29 9.11 10.93 12.75 14.57 16.39 18.21 20.04 21.86 23.68 25.50 27.32
7.50 1.58 3.16 4.75 6.33 7.91 9.49 11.08 12.66 14.24 15.82 17.41 18.99 20.57 22.15 23.74
8.00 1.39 2.78 4.16 5.55 6.94 8.33 9.71 11.10 12.49 13.88 15.27 16.65 18.04 19.43 20.82
10.00 1.39 2.78 4.16 5.55 6.94 8.33 9.71 11.10 12.49 13.88 15.27 16.65 18.04 19.43 20.82
15.00 1.39 2.78 4.16 5.55 6.94 8.33 9.71 11.10 12.49 13.88 15.27 16.65 18.04 19.43 20.82
20.00 1.39 2.78 4.16 5.55 6.94 8.33 9.71 11.10 12.49 13.88 15.27 16.65 18.04 19.43 20.82