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Suggested test tools
Simulating thermocouples and RTDs
for calibration and testing
Thermocouples and RTDs are the most common sensors used in
process temperature measurements.
Simulating a process sensor signal into a process instrument or
control system input enables a technician to verify whether the
device responds correctly to the temperature measured by the
instrument. There are many different ways to simulate these
sensors for testing purposes.
You can use a mV dc source and a mV vs temperature look up table
(below on the left), for simulating thermocouples or a resistance
decade box and resistance vs temperature look up table (below
on the right), for simulating RTDs. This method, however, has
become outdated with modern temperature calibrators that do
the conversion for the user. With modern calibrators, simply select
the sensor type to simulate, input the temperature to source and
connect to the devices under test.
Thermocouple Table –
Temperature vs mV
RTD Table – Temperature vs Resistance
°C
0
1
2
3
0
0.000 0.039 0.079 0.119
10
0.397 0.437 0.477 0.517
20
0.796 0.838 0.879 0.919
30
1.203 1.244 1.285 1.326
40
1.612 1.653 1.694 1.735
50
2.023 2.064 2.106 2.147
60
2.436 2.478 2.519 2.561
70
2.851 2.893 2.934 2.976
80
3.267 3.308 3.350 3.391
90
3.682 3.723 3.765 3.806
100 4.096 4.136 4.179 4.220
°C Ohm Diff.
0
100.00 0.39
1
100.39 0.39
2
100.78 0.39
3
101.17 0.39
4
101.56 0.39
5
101.95 0.39
6
102.34 0.39
7
102.73 0.39
8
103.12 0.39
9
103.51 0.39
°C Ohm Diff.
10 103.90 0.39
11 104.29 0.39
12 104.68 0.39
13 105.07 0.39
14 105.46 0.39
15 105.85 0.39
16 106.24 0.39
17 106.63 0.39
18 107.02 0.39
19 107.40 0.38
°C Ohm Diff.
20 107.79 0.39
21 108.18 0.39
22 108.57 0.39
23 108.96 0.39
24 109.35 0.39
25 109.73 0.39
26 110.12 0.39
27 110.51 0.39
28 110.90 0.39
29 111.28 0.38
7526A
Precision Process
Calibrator
See pg 5
726 Precision
Multifunction
Process
Calibrator
See pg 6
754
Documenting
Process
Calibrator
See pg 5
714
Thermocouple
Temperature
Calibrator
See pg 17
712 RTD
Temperature
Calibrator
See pg 17
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Temperature Applications