Home
What BatteryWatchdog can show and How to Use/Interpret It
This demo is running live from our boat (SNAFU II). The boat is on a swinging mooring in the UK - systems powered by solar panels - access via 4G and the VPN. If you are interested in viewing
your own boat systems via a VPN, all the software is free and Open Source. We charge a small subscription to enable users to use the VPN. Note that this is a VPN
which allows you private access your boat systems, not a VPN to use from the boat for privacy whilst browsing.
Current System
We are running a Raspberry Pi (using a 3B, 4 or 400) which not only supports this BatteryWatchdog but also allows us access to
SignalK feeds and
Live graphs using Grafana. We utilise
Skippers Mate which provides us
with other features. Skipper's Mate software is free Open Source and still available for download. We no longer sell hardware because of issues around
Brexit but you can source your own hardware - details are available in the extensive documentation.
The software currently supports the more recent Epever MPPT controllers which use Modbus (e.g. Tracer-AN Series) and,
from the NASA range, the BM1 battery monitor with Bluetooth connectivity. (See below for more on shunt size.)
This demo shows the current amps and volts via the Epever using our own Open Source BatteryWatchdog gauges.
BM1, BM2 and Shunt
We are using a 200A shunt, not the one provided with the BM1 because of the size of our inverter. So we are running a BM2 head at the chart table so
we can glance at the figures when we're in the saloon, and the software has been modified so that the BM1 works with the larger shunt. This is a simple
modification which you could make yourself. Just ask if you need to know more.
Epever Triron
This is connected to our 320A of solar panels on deck and to our Raspberry Pi via a RS485 cable.
Batteries
Our house battery bank is currently 400Ah of Lead Carbon AGM
installed in 2023.
We also have 2 engine batteries of about 85Ah each, which came
with the boat when we bought her in 2020, which are also charged by the panels. One of the reasons for developing the BatteryWatchdog
software is to provide us with more information on the state of the batteries and the performance of the charging systems (solar and alternators).
As of 2025 we are likely to have a much larger requirement for
electricity and are therefore working on replacing the AGM
batteries with LiFePO4 house batteries and battery to battery
chargers. Watch this space for more on the project. With the
assistance of gauges and graphs the comparison of AGM and LiFePO4
could be intriguing.