Q. I connected a thermocouple to the F2-04THM but the temperature reading is way off or it reads burnout, what's wrong?
A. Make sure that the thermcouple type that you are using matches the type selected with jumpers on the F2-04THM.

Q. I have programmed the multiplexing logic into my 240/250 but the data is never changing and the channel ID bits are not changing. What's wrong?
A. Most likely the pointer data for the slot your THM module is in is not zeroed. If your F2-04THM is in Slot 0 make sure V7660 and V7670 contain zeros, then power cycle the PLC.

Q.Can I field calibrate my F2-04THM?
A. There are no field adjustments for this module but you can use ladder logic to add or subtract a calibration factor.

Q. How can I verify the module is functioning correctly?
A. Thermocouple calibrator. Install the calibrate enable jumper before testing with a thermocouple calibrator. Not all thermocouple calibrators will function with our module. To detect thermocouple burnout, we send balanced currents down each leg of the thermocouple wire, most thermocouple calibrators CANNOT handle this current pulse. We use an NIST traceable thermocouple calibrator - ALTEK Model 422. Be sure to place the calibrate enable jumper on a singl post after testing with a thermocouple calibrator.

Q. How much error will thermocouple extension wire introduce?
A. Thermocouple extension wire has a limit of error from 1.7°C to 2.2°C depending on the type wire. This error can be removed by subtracting the error from your reading in ladder logic.