Schweitzer Engineering Laboratories SEL-787 - Table 4.17 RTD Resistance Versus Temperature

4.50
SEL-787 Relay Instruction Manual Date Code 20081022
Protection and Logic Functions
RTD-Based Protection
RTD Trip/Warning Levels
The SEL-787 provides temperature warnings and trips through use of the RTD
temperature measurements and the warning and trip temperature settings in
Table 4.16.
The relay issues a temperature warning if any of the healthy RTDs indicate a
temperature greater than the relay RTD warning temperature setting. The relay
issues a temperature trip if one of the healthy RTDs indicate a temperature
greater than the RTD trip temperature setting.
To disable any of the temperature warning or trip functions, set the appropriate
temperature setting to OFF.
Only healthy RTDs can contribute temperatures to the warning and trip
functions. The relay includes specific logic to indicate if RTD leads are
shorted or open.
Table 4.17 lists the RTD resistance versus temperature for the four supported
RTD types.
Table 4.17 RTD Resistance versus Temperature
Tem p
(°F)
Tem p
(°C)
100
Platinum
120
Nickel
100
Nickel
10
Copper
–58 –50.00 80.31 86.17 74.30 7.10
–40 –40.00 84.27 92.76 79.10 7.49
–22 –30.00 88.22 99.41 84.20 7.88
–4 –20.00 92.16 106.15 89.30 8.26
14 –10.00 96.09 113.00 94.60 8.65
32 0.00 100.00 120.00 100.00 9.04
50 10.00 103.90 127.17 105.60 9.42
68 20.00 107.79 134.52 111.20 9.81
86 30.00 111.67 142.06 117.10 10.19
104 40.00 115.54 149.79 123.00 10.58
122 50.00 119.39 157.74 129.10 10.97
140 60.00 123.34 165.90 135.30 11.35
158 70.00 127.07 174.25 141.70 11.74
176 80.00 130.89 182.84 148.30 12.12
194 90.00 134.70 191.64 154.90 12.51
212 100.00 138.50 200.64 161.80 12.90
230 110.00 142.29 209.85 168.80 13.28
248 120.00 146.06 219.29 176.00 13.67
266 130.00 149.82 228.96 183.30 14.06
284 140.00 153.58 238.85 190.90 14.44
302 150.00 157.32 248.95 198.70 14.83
320 160.00 161.04 259.30 206.60 15.22
338 170.00 164.76 269.91 214.80 15.61
356 180.00 168.47 280.77 223.20 16.00
374 190.00 172.46 291.96 231.80 16.39
392 200.00 175.84 303.46 240.70 16.78
410 210.00 179.15 315.31 249.80 17.17
428 220.00 183.17 327.54 259.20 17.56
446 230.00 186.82 340.14 268.90 17.95
464 240.00 190.45 353.14 278.90 18.34
482 250.00 194.08 366.53 289.10 18.73