RIGOL DM3068 - Manual (Page 161)

Chapter 6 Specifications RIGOL
User’s Guide for DM3068
6-15
Measuring Characteristics
Measurement Considerations
The built-in cold junction temperature tracks the temperature inside the banana jack. The change of temperature in banana jack might cause additional
error. When using the built-in cold junction compensation, connect the sensor terminal of the thermocouple to the banana jack and warm it up for more than
3 minutes to minimize the error.