Lowering self-consumption on Lynx Shunt + Cerbo GX system

Has anyone managed to reduce the idle draw on a Lynx Shunt + Cerbo GX combination? I'm running a fairly modest off-grid setup in a rural part of Scotland and during the winter months every watt of self-consumption genuinely matters.

My current situation:

• Cerbo GX running continuously for monitoring
• Lynx Shunt for battery management
• A couple of Victron SmartSolar MPPTs
• Fogstar LiFePO4 battery bank (about 10kWh usable)

The Cerbo on its own pulls around 3–4W constantly, which across a dark Scottish winter adds up to a meaningful chunk of my limited solar harvest. I've seen some discussion about putting the Cerbo on a timer or using the relay functionality to power it down during overnight hours, but I'm not sure if that causes any issues with the Lynx Shunt losing its state of charge calibration when it powers back up.

A few specific questions:

1. Does the Lynx Shunt retain accurate SoC data if the Cerbo loses power temporarily?
2. Is there a "low power mode" I'm missing in VRM or Venus OS settings?
3. Has anyone experimented with running a Raspberry Pi with Venus OS instead, and does it actually draw less?

The bigger context is that I also want to eventually add EV charging capability via a Victron-compatible EVSE, and I'd rather sort out the baseline self-consumption before adding more parasitic loads into the mix.

Would appreciate any real-world experience rather than just the spec sheet figures — those never seem to reflect what you actually see in practice.

@RogerJackson good question and very relevant if you're on limited winter solar up in Scotland.

The Cerbo GX itself draws around 1.8–2.2W continuously — not much you can do there short of replacing it with a Venus GX or a Raspberry Pi running VenusOS (which idles lower). The Lynx Shunt adds roughly 0.5W on top.

One thing worth doing: disable unused interfaces in the Cerbo settings — WiFi, Bluetooth, and any unused VE.Can ports all add marginal draw. Also check whether your GX Touch display is sleeping aggressively; the screen itself pulls a few watts when active.

On my narrowboat I run the Cerbo on a separate small relay-switched circuit so I can kill it overnight if I'm not monitoring remotely. Saved me a meaningful chunk across a full winter week. Not for everyone but worth considering.

@RogerJackson I run a Cerbo GX in my van and the scheduled charging/sleep schedules via VRM are worth looking at — you can set the Cerbo to reduce polling intervals which shaves a bit off the idle draw.

Also worth checking whether you've got the GX Touch 50 connected continuously; that screen alone pulls around 2-3W constantly. In my setup I just leave it disconnected unless I actually need it and check via the VRM app instead.

The Lynx Shunt itself is pretty minimal — maybe 0.3-0.5W — so that's not really your culprit. Focus on what's connected to the Cerbo rather than the unit itself.

If you're on a tight winter budget up in Scotland, disabling unnecessary GX services (tank monitoring, generator input etc.) through the menu also reduces background processing load slightly.

@RogerJackson on my narrowboat I've got a similar Victron setup and honestly the GX Touch display was the sneaky culprit for me — it pulls a fair bit on its own. If you're not standing there watching it all day, just leave it unplugged. The Cerbo itself still runs fine without it.

Also worth checking if you've got any unnecessary VE.Direct devices connected that you're not using — each one adds a tiny bit.

For the Lynx Shunt specifically, not much you can do there, it's pretty lean already.

Winter in Scotland is brutal for solar though 😅 might be worth the Fogstar route and just throwing more battery capacity at the problem so idle losses matter less proportionally!

@PanelKate that's a good shout on the GX Touch — I ditched mine on the shepherd's hut build and just use VRM remotely now, makes a surprising difference.

One thing nobody's mentioned yet — check your MPPT sleep thresholds in VEConfigure. If your charge controllers are staying active hunting for solar during long dark nights they'll be pulling more than needed. Also worth checking if the Lynx Shunt itself has any unnecessary auxiliary circuits feeding through it that you'd forgotten about (guilty of this myself, had a random fused run I'd completely blanked on 😅).

@RogerJackson with Scottish winters you really do need to audit every single parasitic draw — I log mine obsessively on a spreadsheet now after a nasty January last year where I nearly flattened my Fogstar cells.

@RogerJackson been down this rabbit hole on the narrowboat. The Lynx Shunt itself is pretty frugal — it's the Cerbo GX sitting there like a nosy neighbour, awake at all hours, that adds up over a Scottish winter.

One thing nobody's mentioned yet: check what's connected via USB. I had a