WattmonMINI3 is an embedded data logging and control system designed for Modbus RTU devices.

Wattmon is a versatile platform which can be configured for countless applications. The inbuilt web server provides all of the tools necessary to customize the device. No programming is required to set up actions based on various triggers, which can output modbus commands, send emails and more.

For pricing details, please contact us.

WattmonMINI3 Spec Sheet


  • RS-485 Modbus RTU port for communication with up to 8 Slaves
  • Modbus TCP Client mode for communication with up to 8 Servers
  • Modbus TCP Server mode to interface with SCADA systems


  • Input voltage range: 6-60V DC
  • Low Power Consumption of < 2 Watts


  • 100 Mbit Ethernet
  • 3G and 4G LTE (via external USB Stick)


  • 512 KB RAM
  • 16 GB MicroSD Card

Data Collection & Export

  • CSV format

Power Requirement

WattmonMINI3 can be powered between 6 and 60V DC and comes with a 12V wall adapter.  It consumes less than 2W


WattmonMINI3 has two ways of connecting to the Internet. The built-in LAN can be connected directly to a laptop or router, and is used for setup and local monitoring. The USB Host port works with a selected number of USB Cellular dongles, allowing both outbound and inbound data via the Internet. Although we provide instructions on configuring your local dongle, not all of them work. Need a compatible USB dongle for remote monitoring? Use one of our Huawei dongles, the E303F or E3531, or E3372h for 4G connections.

Hardware Features

Modbus RTU (RS-485)

An RS-485 Modbus RTU interface is built in and Wattmon acts as a Modbus master to collect data from various devices such as inverters, power meters, current sensors, etc.


Pinout Diagram