Version 3.03
WR14 / WR50-12/13 Winding Resistance Meter Instruction Manual
50
The correction formula:
𝑅
𝑠
= 𝑅
𝑚
𝑇
𝑠
+ 𝑇
𝑘
𝑇
𝑚
+ 𝑇
𝑘
Rs
Resistance corrected
Rm
Measured resistance
Ts
Desired reference temperature
Tm
The temperature at which resistance was/is measured
Tk
234.5 for copper
225.0 for aluminum
(aluminum may be as high as 240)
Alternative: Correction with “alpha25” to calculate Tk with the formula:
𝑇
𝑘
=
1
𝑎𝑙𝑝ℎ𝑎25
− 25
When temperature correction is activated, the Main Test Screen appears as below:
The “T” in the measuring channel box shows that
the displayed resistance value is corrected. In this
example it is corrected to 25 °C using Tk of Copper
and referring to Temperature probe 1.