Hi,

I have a DT80 datataker attached to several type T thermocouples. My issue is that at some points the thermocouple temperature "jumps". It jumps, then continues at the new temperature for a while, then there is another jump and so on. This occurs even when I am not interacting with my setup.
I have attached a graph showing two jumps, one at around 61 s the other at around 68 s. For reference the temperature should be 10 dC and doesn't change over time.
The problem with these jumps is that they are very inconsistent - the change is not the same for each thermocouple, sometimes there is an increase in temperature, sometimes a decrease.

A second question, which is related: the datataker clicks everytime it samples, however every now and then it does multiple clicks at once. What does this "multiple clicks at once" represent?
I have noticed that the temperture jumps happen more often at these multiple clicks, although not at every time and also not restricted to.

I am somewhat new to using datatakers so apologies for the non-technical language. I have looked at the manual and couldn't find anything helpful.

Let me know if anything needs clarifying.
Thanks very much

Hi hp60,

Apology for late response.

The jump happens because auto calibration feature in the logger, there are 2 possible solution:

• you can turn of auto calibration (please see SWITCHES section specially K switch in user manual).
• you can reduce the calibration value from 3 to 1 to get a smaller jump value (please see PARAMETERS specially P0 in user manual).

The first will remove the jump completely while the second if you set Po=0 it will force DT to do auto calibration on every reading which in the end will remove the jump as well.

Best regards,
Rudy Gunawan