Anyone else using a Raspberry Pi to monitor their off-grid setup? Sharing my Node-RED dashboard build

I've been running a small off-grid system at my static caravan in the Brecon Beacons for about 18 months now — 400W of panels, a Victron SmartSolar 100/30, and a 200Ah LiFePO4 battery from Fogstar. For ages I was just glancing at the Victron app when I remembered to, but a few weeks ago I finally got round to setting up a Raspberry Pi 4 to pull everything together into a proper dashboard.

I'm using Node-RED to visualise the data, pulling from the Victron via VE.Direct USB cable into the Pi, and I've added a cheap SHT31 temp/humidity sensor inside the battery box as well. The whole dashboard shows live SOC, solar watts in, load watts out, and battery temp all on one screen. Cost me about £40 all in for the Pi Zero 2W, the USB adaptor, and the sensor — the Pi 4 I already had kicking about.

The bit I'm still struggling with is logging to InfluxDB and getting Grafana set up for historical data. I've followed a couple of guides but I keep hitting permission errors when Node-RED tries to write to the InfluxDB bucket. Not sure if it's a token issue or something with how I've configured the Node-RED InfluxDB node itself.

Has anyone gone down this route with Victron kit specifically? Would love to know if you're using Venus OS Large on a Cerbo GX instead, or whether the VE.Direct-straight-to-Pi approach is working well for others. Also curious what retention policies people are using in InfluxDB — I'm only on a 32GB card so I don't want it filling up too fast.

@Squib30 nice setup — I've got something similar running for my garden office. Victron kit plays really well with Node-RED once you've got the Cerbo GX pulling data over MQTT. If you haven't gone that route yet, the victron-energy nodes for Node-RED are worth looking at — saves a lot of manual parsing.

One thing I'd add: log your data to InfluxDB and front it with Grafana alongside Node-RED. The historical trending is genuinely useful when you're trying to work out if your Fogstar cells are degrading or whether a cloudy fortnight just wrecked your state of charge patterns.

Running mine on a Pi 4 — overkill probably, but a Pi Zero 2W handles it fine if you want to keep power draw minimal on an off-grid setup.

Really nice work @Squib30! I've got a similar setup running at my narrowboat — Victron kit really does make the MQTT/Node-RED integration straightforward once you've got Venus OS configured properly.

One thing I'd add: if you haven't already, look into the Cerbo GX or even just running Venus OS Large on your Pi itself. It gives you a proper VRM portal alongside your local dashboard, which is brilliant for checking in remotely when you're not at the caravan.

Also worth setting up some basic alerts in Node-RED — I've got a Telegram bot that pings me if SOC drops below 20% overnight, which has saved me from a few nasty surprises with the Brecon weather killing solar production for days at a stretch.

What are you using for your battery comms — BMS serial or relying on the Victron SoC estimate?

Really useful thread this. I've got Node-RED pulling data from a Victron Cerbo GX on the boat, and one thing worth adding — if you're logging to InfluxDB, set your retention policy sensibly early on. I made the mistake of letting it run uncapped for months and eventually choked the SD card on my Pi 3B+. Switched to a Pi 4 with a small SSD boot drive and haven't looked back.

Also worth wiring in a low-voltage alert flow that pushes a Telegram notification if the battery drops below, say, 20% SoC. Saved me twice over winter when solar generation was rubbish and I'd forgotten to check the shepherd's hut system remotely. Simple change node into an http request node — fifteen minutes to set up.

@Squib30 what interval are you polling the SmartSolar at?