Node Red en Shelly TIP (from Andy)

Saw this doing the rounds and had to share — been meaning to post about it for ages.

I've been running a Shelly Plus 1PM on my narrowboat to monitor a small 500W grid-tie inverter (yes, I know, slightly unconventional setup 😅), and getting it to register properly as a PV source in Venus OS was genuinely fiddly until I stumbled onto this Node-RED approach.

The basic idea is that you can use Node-RED flows inside Venus OS to intercept the Shelly's MQTT output and essentially tell Victron it's a PV inverter rather than just a generic switch or meter. Once it clicked for me, it opened up all sorts of possibilities.

A few things I'd add for UK folks specifically:

• Fogstar / domestic battery setups — if you're running a DIY bank, getting accurate PV figures into Venus matters more than people realise for SOC calculations
• The Shelly 2.5 is still fairly easy to source here and works brilliantly for split-circuit monitoring on a narrowboat 12V system
• Make sure you're on a recent enough Venus OS build — I had a weird issue on an older Cerbo GX firmware where the MQTT broker kept dropping connections

Has anyone managed to get multiple Shellys registered as separate PV sources in a single Venus install? I've got a second small panel array on the roof and I'm tempted to add another device rather than running everything through one node.

Would love to know what flows people have built — drop them below if you're willing to share. Tiny house folks, curious whether you've had similar results?

@WattVicky solid find — I've got a similar setup on my narrowboat but using a Shelly EM for whole-system monitoring rather than per-device.

The Node-RED integration is where it gets really powerful. I've got flows that:

• Watch the Shelly MQTT topics
• Cross-reference with my Victron Cerbo GX via the Venus OS MQTT broker
• Automatically shed non-critical loads when SOC drops below 40%

The Shelly devices are brilliant value for what they do — proper local API, no cloud dependency if you run your own MQTT broker (I use Mosquitto on a Raspberry Pi 4 sat behind the helm panel).

One thing worth noting for narrowboat folk specifically — the Shelly Plus range handles the humidity better than the older Gen1 units in my experience. Had a Gen1 die in my engine bay within a season.

What broker are you running for the MQTT side?

Really interested in this thread — @WattVicky have you got Node-RED running locally on a Pi, or are you using the Shelly cloud integration? I ask because on my boat I deliberately keep everything local after my 4G connection got patchy going through some of the longer Midlands tunnels and I lost visibility of the whole system for hours.

@ExSquaddie49 the Shelly EM is a cracking bit of kit for whole-system monitoring — I've been tempted to switch from my current clamp meter setup purely for the cleaner data it feeds into InfluxDB/Grafana.

One tip I'd add: if you're on a narrowboat, make sure your Shelly is in a well-ventilated enclosure. Mine ran warm last summer moored in direct sun and the readings started drifting slightly. Simple fix but worth mentioning.

@WattVicky @LizHunt — worth noting that if you're running Node-RED locally on a Pi, you can tie Shelly MQTT data directly into Victron's VRM ecosystem via a Venus OS device. I do exactly this with my garden office setup — Shelly Plus 2PM feeding consumption data into a Cerbo GX over local MQTT, no cloud dependency whatsoever.

Key thing people miss: set your Shelly MQTT broker to point at the Cerbo's IP rather than any external service. Keeps everything local and removes the Shelly Cloud latency issue entirely.

For the narrowboat context specifically, I'd also flag that the Shelly EM's clamp-based monitoring suits AC systems well, but you'll want to verify your CT clamp orientation carefully — got mine backwards initially and spent an afternoon wondering why my "consumption" figures looked inverted.