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Upgrading your firmware

Upgrading your Wattmon Firmware

1. Download the latest firmware from
2. Unzip this file into a folder on your computer, the file inside the zip is called image.hex
3. Log into your wattmon device through your browser.
4. On the System menu, click on File manager.
5. Click add files which is a button at the top right side.
6. Now click the choose file or add file button (the label will change on different browsers.
7. Wait for the file to upload. This will take about 30 seconds, and a small text will appear below the button saying: uploaded images.hex... Ok
8. On the system menu, click Firmware Update and wait about one minute.
9. Reopen your wattmon link and log in again. At the bottom of the main page you will see the new firmware version.
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Aquaponics and Wattmon


I have been interested in aquaponics for several years and built a variety of systems using off the shelf components. The largest system consisted of a 6000 liter fish tank and 5000 liters of grow beds. This was much larger than our first system which was a small tank with just a few beds. One of the big challenges in an aquaponics system is to keep the water running smoothly to oxygenate the water and to provide nutrients for the plants. In south India we face terrible power cuts lasting for hours at a time, and that means that everything needs to run off batteries.  I plan to customise wattmon for aquaponics systems that can run off a single solar panel and small battery. I want to integrate flow sensors, relays, ph meters, temperature sensors and solenoids to log and control the system fully making it more robust and at the same time easy to monitor from anywhere. I believe that aquaponics holds great potential for urban farming and although our tests have not yielded huge amounts of crops, I would like to continue with the research. I will be posting pictures of the system as it gets developed, but the idea is to make an electronic kit that can be installed on any aquaponics system to understand the system better and respond to problems more quickly. For some pictures of our greenhouse check out
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Wattmon as a platform

This blog so far has covered both hardware and software aspects of wattmon. I have tried to give potential developers a good idea of what is under the hood. I see potential for usage in many different fields.

  • As an educational tool, wattmon is an easy way to learn programming concepts. Just plug in the wattmon box, bring up a browser and start coding using the built in editor.
  • As a data logger: plug in your own sensors to the wattmon box using any modbus compliant hardware and write a simple logger script that stores your data as a csv file.
  • As a home automation server: read inputs from around the house through modbus compliant devices or wattmon sensors and switch on or off loads based on that data. Schedule cron jobs to run your custom scripts to control devices at specific times.
  • As a PLC: Control a machine through inputs and output of Wattmon.
  • As a small embedded web server: put small files and scripts that you want access to without having to boot up your server. That could be your excel sheet, HTML website, or even PHP code adapted to run on wattmon.

There are countless possibilities and as a developer you would need to customise it to your requirements. It does not have the flexibility of an embedded Linux computer but it also not intended to compete with it. Wattmon provides a stable scripting engine with web preinstalled web server and data collection mechanism, making it easy to focus on the task you want to accomplish rather than how to install a web server and how to interface with modbus.

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Data logging

I always find data fascinating. It gives me an insight into the overall functioning of a system. Data can be used to make intelligent decisions based on past events or trends. Data gives us visual graphs of performance and often a single glance at a group of data points presented the right way gives us a wealth of information.

Wattmon captures data on current and voltage input and load, and logs average values on a per-minute basis. Wattmon also computes battery capacity every minute and updates internal registers. It also has a system log for events of importance. All these collected data points can be used at any point to figure out the system state of both wattmon and the solar setup and battery bank. A battery status Graph immediately shows you the lowest and highest state of charge throughout the day making it simple to see if your batteries are either too depleted or too quickly charged.

Battery Status

Battery Status Graph per day

Solar Input Graph

Solar Input Graph per day showing KWh generated

Load Graph and Main Charge

Load and grid charge graph showing reduced charge hours compared to before

The solar and inverter graphs show watts generated and consumed throughout the day with a kwh total. Wattmon has helped me personally reduce my grid energy consumption at the cynergy office. I have a 1kw solar array and two 180 ah batteries. My inverter cum grid charger was always connected to the grid, meaning that my batteries were always full and the solar power was totally wasted. In addition, I was being billed for all my usage of energy. Within one day of installing wattmon it was evident that I had sufficient solar energy to run my office totally off the grid most of the time. The wattmon device communicates with a wattmon relay to switch on and off the grid charger when required. I have set it so my battery never depletes below 10% (it is at 90% state of charge) which will give me a longer life. So generally at night my relay charges the batteries for half an hour or so, and this may happen a few times during every night. So I have cut my reliance on the grid almost completely thanks to wattmon.

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