NEW PRODUCT – Pax Instruments T400 Temperature Datalogger Set


NEW PRODUCT – Pax Instruments T400 Temperature Datalogger Set

The Pax Instruments T400 Temperature Datalogger is an open source four-channel thermocouple temperature datalogger based on the Arduino Leonardo platform.

The Pax Instruments T400 datalogger is designed to be out of the box ready for professionals and hobbyists alike. If you need a temperature datalogger that works every time, this is the device for you!

Measurements can be logged to the provided microSD card, graphed on screen, and printed to the USB serial port. The T400 is a great tool for anything from live thermal process monitoring in the lab to long-term environmental data collection in the field.


The hardware and software design files are available to you at no cost to use, modify, or redistribute. This allows you and others to extend the devices capabilities or tailor it to your specific application.

Arduino-compatible hardware means while hacking on the platform you will be able leverage the work of others while sharing your own work with large community of hackers and makers. Sharing is caring.

Readings can be saved to a microSD card in standard CSV format for processing in Microsoft Excel, LibreOffice, or your favorite data analysis tool. Readings can also be captured live via the USB serial port. This is perfect for live process monitoring in lab experiments or connecting to an internet-enabled device.


For more information check the Pax Instruments product page.

We have a ton of AVR Development boards and temperature sensors in the store if you’re looking for a more DIY project. Our MCP9808 High Accuracy I2C Temperature Sensor Breakout Board is very accurate/precise and similar to the temp. sensor used in this Pax T400. And we also have a few different options of boards with the same DS3231 RTC used in this datalogger too!


  • The T400 runs on the ATmega32u4 AVR processor
  • The MCP9800 temperature sensor is used for cold junction compensation.
  • The MCP3424 analog-to-digital converter measures the voltage produced by each thermocouple.
  • The DS3231 real time clock is used to trigger readings. Between readings the device is put into low power sleep mode. The RTC wakes up the unit to take a reading. This gives a longer battery life.
  • The T400 uses a standard BL-5C battery. This is great for battery replacement in the field.
  • The generous 132×64 LCD is capable of displaying the current temperature for each thermocouple as well as a graph of the most recent readings.
  • Thermocouples connect via standard mini thermocouple connectors. The T400 is compatible with a wide variety of K-type thermocouple sensor types from stainless steel probes to rolling surface-contact sensors.

Set contains:

  • 1x T400 Temperature Datalogger
  • 1x BL-5C battery (installed)
  • 1x Stainless steel probe thermocouple
  • 4x Wire type thermocouple
  • 1x North American USB wall charger
  • 1x MicroUSB cable
  • 1x 256 MB MicroSD card

In stock and shipping now!

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1 Comment

  1. If you work around 3D printers, or any kind of managed thermal process, you’ve undoubtedly come across something called a PID controller. It’s a way of managing heaters so that they reach and maintain a steady temperature.

    Setting them up requires calibration, and that calibration requires monitoring the temperature, and measuring the time interval of any fluctuations. This is a tedious process that requires watching the temperature reading go up and down, expecially tedious when the fluctuations are very long.

    The T400 is EXACTLY the right tool for doing this right, and removing the tedium. It lets you plug in multiple temperature sensors, and monitor their readings over VERY long time spans if necessary. Think of it as timelapse for temperatures.

    If you need it, this thing is a godsend – and a bargain.

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