Table of Contents
WattmonMINI
The WattmonMINI is a reduced version of the WattmonPRO with a single Modbus RTU port. It is a smaller and more cost effective product with less features, designed for the sole purpose of collecting data over RS-485 and transmitting it to the web: current sensors, power meters, inverters and charge controllers can all be connected to the Modbus for remote monitoring and control.
Compared to the PRO and the MEGA, which support Modbus, RS-232 Serial and several other I/Os, the MINI supports only RS-485 Modbus RTU/TCP. Although it does not have the I/O connectivity of the PRO and the MEGA, the MINI has the same “look and feel,” with an identically functioning firmware, OS and web interface. The MINI utilizes the same Ethernet and USB GPRS/3G/4G LTE interfaces as any of the Wattmons including its predecessor the PRO.
For power the MINI has a wide input voltage range of 12-24V DC.1) Similar to the PRO and the MEGA it consumes less than 2 watts of power without accessory devices.
The MINI can be used for any RS-485 application in monitoring, control and data logging for the IoT. But particularly noted applications include:
- Inverter Monitoring - Inspect generation and efficiency of gridtie and hybrid inverters
- AC Power Monitoring - Supervise load and performance of substations and mini-grids
- Off-Grid Battery Monitoring - Observe battery voltage, current, SoC, charging trends and health over time
- Zero Export & DG Protection - Reduce active output power of multiple inverters to regulate energy generation
Overview - Introduction to the features of the WattmonMINI
Quick Start Guide
The Quick Start Guide is a regularly updated manual that sheds light on some of the basic and/or essential configuration for the WattmonMINI running the latest WattmonOS version.
User Manuals
These User Manuals, while initially written specifically for the WattmonPRO, are relevant to the WattmonMINI too:2)
The Latest and Most Capable Wattmon was Introduced Next:
- The WattmonMEGA has 512KB RAM, 100mbps Ethernet, and operates at 200MHz making it over twice as fast as the PRO.
1)
There was an early release of the MINI that was powered with an inbuilt AC adapter and functioned on anything between 80 and 240V AC. This AC version of the MINI is no longer available, and only a few were produced. In all other respects it is identical to the current DC powered model. For those that might have one of these AC powered MINIs: WattmonMINI AC DataSheet 
2)
These User Manuals are somewhat “dated,” having been written during times when the newer Wattmons had not yet been released, and they sometimes feature or show specific Modules or Hardware that are obsolete (no longer available). However, the OS is the same for all of the Wattmons. Therefore the hardware differences are the only thing to keep in mind when using these manuals, especially the Original Wattmon and WattmonMINI which do not have the additional I/O ports that are provided on the WattmonPRO and WattmonMEGA.