EITB isolated thermocouple layer

The EITB provides eight (8) channels of isolated thermocouple signal conditioning. The EITB is factory-configured for J, T, E or K type thermocouples and is operational over the full range of the thermocouple. Each channel has individual cold junction compensation and a notched filter processor that generates about seven (7) samples per second. Each channel is also isolated from the other channels to 500 volts, which allows the thermocouples to be attached to structures that have large differences in ground potential. The thermocouples are connected to the eDAQ layer using the standard Omega miniature thermocouple connectors located on the front panel.

The EITB uses the industry standard software compensation algorithm to generate the temperature data samples. The EITB first measures the cold-junction compensation (CJC) temperature and converts it to the equivalent microvolt value using a high-resolution lookup table. The EITB then subtracts the CJC equivalent microvolt value from the thermocouple’s output microvolt value. The temperature is found using another high-resolution lookup table. The lookups are based on the ITS-90 Thermocouple Direct and Inverse Polynomials.

NOTE
Thermocouple leads should not exceed 30 meters in length from connector to tip.

This diagram shows the thermocouple connectors on an EITB layer configured for K-type thermocouples.

Wiring diagram