Pax Instruments T400 Temperature Datalogger Set

The Pax Instruments T400 is an open-source, four-channel thermocouple temperature datalogger based on the Arduino Leonardo (ATmega32U4) platform. It logs measurements to a microSD card in CSV format, displays real-time readings and graphs on the built-in LCD, and outputs data via USB serial for live monitoring.

This set includes the T400 datalogger, a BL-5C battery, five thermocouples (one stainless steel probe and four wire type), a USB charger, cable, and microSD card — everything needed to start logging immediately.

Key Features

• Four Thermocouple Channels – Monitor up to four K-type thermocouples simultaneously
• 132 × 64 LCD Display – Shows live temperatures and a graph of recent readings
• MicroSD Logging – Saves data in standard CSV format for Excel, LibreOffice, or other tools
• USB Serial Output – Stream live readings to a computer for real-time process monitoring
• Open Source – Hardware and software design files freely available to modify and extend
• Arduino Compatible – Built on the ATmega32U4 platform for easy customisation
• Low Power Sleep Mode – DS3231 RTC triggers readings between sleep cycles for extended battery life
• Replaceable Battery – Uses standard BL-5C batteries for easy field replacement

Specifications

• Processor – ATmega32U4
• ADC – MCP3424 (four-channel thermocouple measurement)
• Cold Junction Sensor – MCP9800
• RTC – DS3231
• Display – 132 × 64 LCD
• Thermocouple Input – 4× standard mini thermocouple connectors (K-type)
• Storage – MicroSD card (CSV format)
• Battery – BL-5C (replaceable)
• Connectivity – Micro-USB (charging, serial data)

Package Contents

• 1× T400 Temperature Datalogger
• 1× BL-5C Battery (installed)
• 1× Stainless Steel Probe Thermocouple
• 4× Wire-Type Thermocouples
• 1× USB Wall Charger
• 1× Micro-USB Cable
• 1× 256 MB MicroSD Card

Ideal For

• Lab thermal process monitoring
• Long-term environmental data collection
• Soldering and reflow oven profiling
• HVAC and industrial temperature logging