RIGOL DM3068 - Manual (Page 76)

RIGOL Chapter 2 Front Panel Operations
User’s Guide for DM3068 2-34
TC
The TC (thermocouple) is one of the most commonly used industrial temperature
detection device. It converts the temperature value into voltage reading, and has a
very large temperature measurement range.
The common thermocouples are B (Pt Rh 30- Pt Rh6), E (NI CR-WRCK), J
(Fe-WRCK), K (NI CR-NiSi), N (NiCrNi-NiSi), R (Pt Rh13 -Pt), S (Pt Rh10-Pt) and T
(Cu-WRCK). Among them, B, R and S are precious metal thermocouple, while E, J,
K, N and T are cheap metal thermocouples. For the reference table about each
thermocouple, please see the ITS-90 standards.
The DM3068 provides two cold junction compensation modes: internal cold
junction temperature & user-defined cold junction temperature.
Internal cold junction temperature refers to the internal temperature of the
banana jack detected by the multimeter. Connect the thermocouple wire to the
inside of the banana jack and prevent air flow from interfering the temperature
around the banana jack. The radiating structure on the banana jack connected
with the thermocouple wire would cause additional cold junction temperature error.
About 3-minute warm-up is needed to build up the thermal balance after the cold
junction is connected.
User-defined cold junction temperature refers to the temperature at the cold
junction compensation point of the thermocouple. The internal temperature of the
banana jack might be different from the actual temperature at the cold junction
compensation point. If external cold junction compensation equipment is used, the
thermocouple voltage signal compensated can not be connected to the banana
jack through the compensation lead; otherwise, additional cold junction error will
be caused. The accuracy of the measurement when using simulated cold junction
depends on the accuracy of cold junction compensation.
To use the TC sensor, you should select the type of the thermocouple and the
compensation mode of the cold junction.
Press TC  Type to select the desired thermocouple type and press
.
Press TC  JUNC, select INT or SIM to input correct cold junction temperature
(with -273 and 999) and then press
.