Anyone else had issues with a Victron SmartSolar 100/30 dropping connection to the VictronConnect app mid-session?

Been using my 100/30 MPPT for about eight months now, paired with a 200Ah lithium (Battle Born) and two 175W panels wired in series giving me roughly 40V Voc. Generally brilliant bit of kit, no complaints on the actual charging side of things.

The problem I keep running into is the Bluetooth connection to VictronConnect on my Android phone (Samsung S21, latest app version) dropping out after maybe 10–15 minutes of being connected. It doesn't crash the app, it just silently disconnects and I have to go back in and re-pair. Sometimes it won't find the device at all for a minute or two. I'm typically standing about 3–4 metres away with no walls between me and the controller, so it's not a range thing.

I've tried forgetting the device and re-pairing from scratch, and I've updated the firmware on the MPPT to the latest version (v3.14 I think). Made no difference whatsoever. I've also seen a couple of posts on the Victron Community forum suggesting it might be a known Android/BLE issue, but nothing conclusive.

Has anyone cracked this, or is it just something we have to live with? Wondering if switching to a Raspberry Pi running Venus OS would give me a more stable monitoring setup, or whether that's overkill for a relatively simple single-battery system.

@SteveBurns yes, had exactly this on my boat setup. Pairing a Victron SmartSolar 75/15 via Bluetooth and it would just vanish mid-session, sometimes after 30 seconds, sometimes a few minutes in.

Turned out my phone's battery optimisation was aggressively killing the Bluetooth connection in the background. Once I excluded VictronConnect from battery saver on my Android, it became rock solid.

Worth also checking:

• Are you within about 10 metres when it drops?
• Any other Bluetooth devices nearby competing for the connection?

I've also read that the firmware on some units had a known Bluetooth stability issue — worth checking you're on the latest via VictronConnect itself. Mine updated automatically once I got a stable connection long enough to push it through.

Is it dropping completely or just freezing on screen while still technically connected?

Has anyone checked whether it's specifically dropping during high charge current periods? I noticed on my Fogstar-paired setup that the Bluetooth seems to struggle when the MPPT is working hardest — almost like the processor is prioritising the charging algorithm over maintaining the BT stack.

Worth checking:

• Is the dropout happening around solar noon?
• What's your phone's Bluetooth version?
• How far are you from the unit when it drops?

Also wondering if firmware version matters here — @SteveBurns are you on the latest? There were some VictronConnect app updates recently that apparently improved BT stability, but I'm not 100% sure if they addressed this specific issue or whether it's more of a hardware limitation on the 100/30 specifically.

Hey @SteveBurns, I had something similar with my 100/20 last spring. Worth checking whether your phone's battery optimisation settings are killing the Bluetooth connection in the background - Android is particularly aggressive about this. Go into your app settings and set VictronConnect to "unrestricted" battery use. Made a massive difference for me.

Also worth making sure your firmware is up to date on the MPPT itself - there was a patch a while back that addressed some BT stability issues. You can check and update directly through VictronConnect when you do manage to hold a connection.

@WonkySparky raises an interesting point about high current periods too - could be thermal related if the unit is working hard. Where have you got yours mounted? Mine was in a poorly ventilated spot initially which didn't help matters.

Hey @SteveBurns, one thing worth trying that nobody's mentioned yet — have you checked the distance between your phone and the MPPT when it drops? Bluetooth on these units can be surprisingly fussy about range and obstructions, even a metre or two through a bulkhead or cabinet can cause instability. Also worth making sure you're on the latest VictronConnect app version, as there were some Bluetooth stability fixes pushed out relatively recently. The other thing I'd look at is whether there are other Bluetooth devices nearby causing interference — I had a similar intermittent dropout on my 75/15 and it turned out my inverter remote was essentially crowding the channel. Updating firmware on the MPPT itself via the app (when you can keep it connected long enough!) sorted it completely for me.