Reading Data - ICP DAS USA tM-TH8 User Manual

4.2 Reading Data

If the data read from the input channel is not correct, first
check the following:
Ensure that the type code and data format settings are

correct. For the tM-TH8, the type code is set by using
the $AA7CiRrr command, see Section 2.10 for details.
The data format is set by using the %AANNTTCCFF
command. For the Modbus RTU protocol, the type
code is set by using sub-function 08h of the function
46h.
Connect a resistor, instead of thermistor sensor, using

the thermistor connection as shown in Section 1.6. The
resistance of the resistor should be less than 180000
ohms. Change the data format to ohms, see Sections
1.10 and 2.1, and check whether the data reading is
correct.
If the resistance read by the module is still incorrect,

then it may be because the calibration parameters
stored in the non-volatile memory are corrupted, which
means that the module should be recalibrated. Be sure
to read Section 1.9 in detail before performing the
calibration. For the tM-TH8, you can send the $AAS1
command, see Section 2.18 for details, to reload the
factory calibration parameters.
tM-TH8 User Manual, Rev: A1.1 7MH-018-A11 133