3. Calculation of coil temperature rise when R initial and R final are known:
Delta T = (234.5 + T1) (R2/R1 - 1)
Delta T = Temperature rise (°C)
T1 = Initial temperature (°C)
R1 = Initial resistance (Ohms)
R2 = Final resistance (Ohms)
R2 = K2R1
Temperature can also be found by making the R2/R1 ratio = the
coefficient of correction graph in Fig. 2, and then finding the corresponding temperature.
Catalog indicates coil resistance of 290 ohm at 25°C. What is the value at 125°C?
From the chart: 290 x 1.39 = 403.31 Ohms.
|Date of issue: 6/00||- 16 -||Page 2 of 2|