Usually when there is a problem with the temperature readings on a TC-08 it is due to one of the following reasons: 1) You are using it on a Laptop with the power supply connected, thus causing a ground loop issue. If this is the case then try disconnecting it form the line/mains and leave it floating. 2) The thermocouple has a voltage injected into it which exceeds the common mode rejection ratio of the TC-08, ensure that the thermocouple is getting a voltage to it.
![เปิด อาณาจักร หมื่นล้าน "สาระตั้ม" l [Nickynachat]](http://i.ytimg.com/vi/3XE0nPF4YkQ/mqdefault.jpg)
what is the cause of having a negative temperature reading on a heated heat cartridge when monitored with pico logger
Usually when there is a problem with the temperature readings on a TC-08 it is due to one of the following reasons:
1) You are using it on a Laptop with the power supply connected, thus causing a ground loop issue. If this is the case then try disconnecting it form the line/mains and leave it floating.
2) The thermocouple has a voltage injected into it which exceeds the common mode rejection ratio of the TC-08, ensure that the thermocouple is getting a voltage to it.