Connecting A Sensor With A Pt-100 Thermistor; Connecting A Thermistor - Kipp & Zonen LOGBOX SE Instruction Manual

8.5 Connecting a sensor with a Pt-100 thermistor

8.6 Connecting a thermistor.

It's possible to connect up to four thermistors on the analog single ended inputs AIN1 to AIN4.
The LOGBOX SE allows you to connect one Pt-100 temperature sensor:
-AIN9+ & AIN9- voltage over 100Ω 0.05% 5ppm/ºC
reference resistor
I = V / 100
measure AIN9
-AIN10+ & AIN10- voltage over Pt-100 thermistor
R = V / I R = 100 x AIN10/AIN9
Pt-100 AIN10 measure Pt-100
The ratio selection in the analog setup page can take care of the calculations
needed. Range should be 78mV.
After connecting the Pt-100 it's still possible to connect up to two sensors on
the differential analog inputs AIN 11 and AIN12.
In the illustration the 10K thermistor is connected to AIN 1 but in practice it
can be connected to any of the four analog single ended inputs AIN1 – AIN4.
The polynomials for AIN1&2 are different from the ones for AIN3&4 as these
have a voltage divider and low 13.2kΩ input impedance.
The thermistor can be connected to GND or VREF and polynomials change
accordingly.
It`s common for a pyrgeometer, pyrheliometer and high-end pyranometer
to have a 10K thermistor and four of these instruments in total can be
connected.
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