National Instruments Module SCXI-1503 - Manual (Page 37)

Chapter 4 Theory of Operation
© National Instruments Corporation 4-7 SCXI-1503 User Manual
defined as the change in RTD resistance from 0 to 100
°C, divided by the
resistance at 0
°C, divided by 100 °C:
where
R
100
is the resistance of the RTD at 100
°C.
R
0
is the resistance of the RTD at 0
°C.
For example, a 100
Ω platinum RTD with α = 0.003911 has a resistance of
139.11
Ω at 100 °C.
Figure 4-3 displays a typical resistance-temperature curve for a 100
Ω
platinum RTD.
Figure 4-3. Resistance-Temperature Curve for a 100
Ω
Platinum RTD,
α
= 0.00385
α(Ω/Ω/°C)
R
100
R
0
–
R
0
100 °C Ч
----------------------------- =
480
400
320
240
160
80
320 400 480 560 640 720 800 880 0 80 160 240 960