SolarHistory.csv sampling rate

Been digging into the data logging side of my Victron BlueSolar MPPT 100/20 lately, and hit a bit of a wall that I suspect others have run into.

When I export the SolarHistory.csv via VictronConnect on my phone, I'm only getting one data point per day — basically just the daily yield summary. That's fine for a rough overview, but it's pretty useless if I'm trying to understand what's happening during peak generation hours or troubleshoot why my garden office batteries aren't charging as aggressively as I'd expect on a clear afternoon.

A few things I'm wondering:

• Is there any way to increase the sampling rate on the MPPT itself, or is this a fundamental hardware limitation?
• Does adding a Cerbo GX or similar device change what gets logged? I've seen mention of VRM portal giving more granular data but I'm not clear on whether that depends on the GX device doing the heavy lifting
• Has anyone had success pulling more detailed data via VE.Direct to something like a Raspberry Pi?

I've got solar feeding the garden office and also want to eventually manage EV charging intelligently off the array, so proper time-series data really matters for my planning — daily summaries just don't cut it for that kind of load modelling.

Feels like Victron's hardware is excellent but the data granularity available without buying into the full GX ecosystem is a bit limited. Or am I missing something obvious?

What are others doing to get decent resolution logging on a budget?

@KenCross yeah the CSV export is a bit of a pain — it's daily aggregates only, not live samples. You're essentially getting peak power, yield kWh, and that's about it per day.

If you want proper granular data you need VRM Portal connected via a Cerbo GX or even a cheap Raspberry Pi running Venus OS. That logs every 15 minutes (or tighter with some tweaking).

Alternatively the Victron MPPT via Bluetooth streams live data — you can grab that with a Python script using the vedirect library if you're feeling nerdy.

Had the same frustration with my garden office setup. Ended up chucking a Cerbo in and now VRM gives me proper graphs. Worth it if you're serious about monitoring.

The CSV is really just a quick sanity check tool tbh, not built for analysis.

@KenCross @QuietTrekker is right about the daily aggregate limitation, but worth knowing there's a workaround if you want finer granularity.

The real-time data lives in VRM Portal rather than the local CSV export — if you've got a GX device (Cerbo, Venus GX, etc.) logging to VRM, you can pull 15-minute interval data going back months. The API is fairly well documented too, so scripting your own exports is very achievable.

Alternatively, if you're running a Raspberry Pi or similar, Node-RED with the Victron nodes lets you sample MPPT data at whatever interval you choose and push it into InfluxDB/Grafana. That's exactly what I've got running in my Vivaro — logs every 60 seconds, and the visibility it gives you over your charge curves is genuinely transformative for optimising panel placement and battery health.

@KenCross this is frustrating me too — I've got a 100/30 on my narrowboat and the daily aggregates are nearly useless for working out whether I'm actually catching the morning sun properly before I move off.

@VivaroWanderer curious what your workaround is? Are you using a Raspberry Pi with the VE.Direct cable to log live data? I looked into that route but wasn't sure if the 100/20 supports it the same way as the larger units.

Also worth noting — if you're just after peak wattage and rough daily shape, the VRM portal does give slightly finer granularity than the local CSV export, but you obviously need a GX device or Cerbo for that, which feels like overkill for a small setup.

@Emma1996 welcome to the forum — great to see another narrowboat setup here, you'll find loads of useful knowledge from the regulars.

To add to what's already been covered: if you want sub-daily resolution without a GX device, the Bluetooth API is your friend. There are Python libraries that can poll your MPPT every few seconds via BLE and write timestamped CSVs yourself. I do exactly this for my static caravan setup — running a Raspberry Pi Zero W alongside my Victron kit.

Key fields worth capturing beyond what the native CSV gives you:

• Panel voltage & Panel current (calculated power)
• Battery voltage
• Charge state (bulk/absorb/float transitions are genuinely useful)

The vedirect Python library handles this cleanly over the VE.Direct cable if Bluetooth feels unreliable on your boat.

Hey @KenCross and @Emma1996 — worth knowing that if you've got a Raspberry Pi or similar kicking about, you can pull real-time data directly from the MPPT over VE.Direct using Victron's vedirect.py script and log it at whatever interval you like. I'm running it at 60-second samples on mine and storing to a simple SQLite database. Gives you proper granular data rather than the daily summaries.

@Emma1996 especially useful on a narrowboat where your generation profile changes constantly depending on mooring orientation and whether you're cruising — the daily aggregates really do hide what's actually happening.

The VE.Direct USB cable is about £20-25, which isn't too painful. Happy to share my logging script if anyone wants a starting point — it's nothing fancy but it works reliably.

Same issue on my motorhome setup — the daily history is basically just a highlight reel, not much use for spotting shading problems or working out actual peak output windows.

@Shunt_Guy the RPi route is solid but a bit overkill if you just want better logging. I went down the VRM portal path instead — free to set up and if you've got a GX device (or a cheap Cerbo) you get proper interval data logged to the cloud. Not quite real-time granularity but way better than the CSV exports.

That said, without any GX device you're a bit stuck with what VictronConnect gives you natively. Might be worth @KenCross checking if a Venus OS on a Pi is worth the faff — Victron's own image, keeps it in the ecosystem.