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For this example where the sensitivity is 10.60 µV/W/m2:
A0 = 0
A1 = 94.33962
A2 = 0
A3 = 0
9.6.2
Polynomials for Thermistors
This section will explain how to use standard or create your own polynomials to be applied when you are using Pt-100 or
TH10K components with given specifications.
Standard polynomials for 10k thermistor to GND, 10k resistor to V
For AIN1 and 2:
y = -1.52813E-08x
For AIN3 and 4:
y = -1.39006E-07x
Standard polynomials for 10k thermistor to VREF, 10k resistor to GND
For AIN1 and 2:
y = 1.52813E-08x
For AIN3 and 4:
y = 1.39006E-07x
y= A3 x
9.6.3
Polynomials for Pt-100
With the excitation jumper placed there will be a current of approximately 600µA available to flow through the 100Ω series
precision resistor and Pt100 thermistor. (see section 9.5 for connections)
AIN9 is used to measure U
RESISTOR
Expected voltage is in the range of 60mV and always positive and unipolar.
I
= U
/ 100
MEASURE
RESISTOR
AIN10 is used for measuring the Pt-100 voltage U
R
= U
/ I
= 100 * U
Pt-100
Pt-100
MEASURE
Calculation of the temperature can be done on the computer after receiving the logged data.
or the RATIO function in the Analog setup can be used.
Inputs AIN9 - AIN12 offer ratio measurements by checking the RATIO box in the Analog window
It's designed for Pt-100 measurements, where AIN9 is connected to a high precision 100ohm reference resistor and
AIN10 is connected to Pt-100 sensor. This way the user can measure temperature with 4 wire method (for highest
precision).
+ 6.29616E-05x
–1.23747E-01x + 1.11104E+02
3
2
3
+ 3.42417E-04x
2
– 3.47914E-01x + 1.63139E+02
– 5.16481E-05x
+ 9.54629E-02x – 4.35227E+01
3
2
3
– 7.00125E-04x
2
+ 1.24218E+00x – 7.38502E+02
+ A2 x
+ A1 x + A0 as used in the LOGBOX SE
3
2
.
and again the expected voltage is in the range of 60mV and unipolar.
Pt-100
/ U
Pt-100
RESISTOR
24
REF
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