How to increase precision on TM5 thermocouple modules?

TM5SAIxTH modules can be used with "external compensation" and "internal compensation".
To increase precision, external compensation should be used.
An additional temperature sensor is needed (PT100 or PT1000). This sensor has to be mounted on the wiring terminals of the thermocouples.
The wire section between TM5SAIxTH and thermocouples wiring terminals has to be made of copper: see attachment "extThermoCompensation_schematics.jpg".

External compensation has to be activated in module configuration: see attachment "activateExtCompensation.jpg"

And temperature from the PT100/1000 should be fed to the compensation input of the TM5SAIxTH module: see attachment "SoMachineThermoCompensation.jpg". Here a global variable "i_PT100temp" is declared.

Publié pour:Schneider Electric Belgium