It is possible to use THERMOCOUPLE-4 as a standalone thermocouple amplifier or as a peripheral to a microcontroller system. It can be used in almost any application or system to amplify and condition the raw voltage output from thermocouples. Featuring four socketed LT1025 ICs, THERMOCOUPLE-4 provides amplification, and filtering for E, J, K, R, S and T type thermocouples. Conditioned output voltages for four thermocouple channels are available on a 26-pin dual-row pin header.
It is recommended to use this board in combination with the DAQ-2543 or DAQ-128 analog-to-digital converter board.
See also the THERMOCOUPLE-4A which adds cold junction compensation, providing less initial uncalibrated temperature error (0.5°C instead of 2°C).
Stack Together for Up to 64 Thermocouple Inputs Each THERMOCOUPLE-4 peripheral board provides four inputs. This means you can connect four thermocouples to the same THERMOCOUPLE-4 board.
Two THERMOCOUPLE-4 boards can be stacked for a total of eight thermocouple inputs. The thermocouple stack can be installed on top of the DAQ-2543 board. The DAQ-2543 board can be installed on top of your microcontroller system.
If you need 16 thermocouple inputs (four THERMOCOUPLE-4 boards) there is a different approach: The DAQ-128 peripheral board operates on I2C bus. Each board has a 3-bit address selector. Thus you can replace a DAQ-2543 with a DAQ-128 in the previous 8-input setup. To provide eight more inputs, you can use another DAQ-128 board. Two extra THERMOCOUPLE-4 boards will be installed on top of the second DAQ-128 board. The second setup can be connected to the first setup using a ribbon cable.
Theoretically, you can build a setup with 64 thermocouple inputs in that manner — one DAQ-128 for every two THERMOCOUPLE-4.
Thermocouple Input Board Features
Users of MicroTRAK and MINI-MAX systems take note: To use this board as a peripheral, you must connect it to a DAQ-2543 or DAQ-128 which then connects to your system, as this board does not have the 2×10-pin expansion header used on MINI-MAX CPU modules. The one exception is the MINI-MAX/51-F, which has the 26-pin header used by this board so you can connect it directly.
- Uncalibrated cold junction compensation error: 2 °C
- Gain error: 0.2% of full scale
- 26-pin analog connector compatible with MINI-MAX/51-F, DAQ-2543 and DAQ-128 boards
- 8–pole screw terminal for four thermocouple connections
- Single +5V power supply comes through analog connector
- Dimensions: 2.35 × 2.40 inches (5.97 × 6.10 cm)
- Mounting holes of 0.138 inches (3.5 mm) on the four corners
- 0° to 70° C operating, -40° to +85° C storage temperature range
- 2-layer PCB for maximum reliability