Ladeunterbrechungen der MPPTs mit Venus OS 3.75

Has anyone else noticed their MPPT dropping to zero output since updating to Venus OS 3.75?

I've got a Victron SmartSolar 100/30 on my motorhome setup with a Fogstar Drift 100Ah LiFePO4, running through a Cerbo GX. Since the update, I'm seeing the MPPT completely cut out around mid-morning — usually just as the battery is approaching full. No faults showing on the BMS, no alarms on the VRM portal, it just... stops. Then after a few minutes it kicks back in as though nothing happened.

My gut says it's something in the new absorption/float handoff logic within 3.75, but I'm not certain.

A few things I'm wondering:

• Is this related to the ESS assistant or DVCC settings? I've got DVCC enabled with the BMS in control of charge limits
• Could it be the Cerbo telling the MPPT to back off because it thinks the battery is full, even when the BMS hasn't actually sent a charge-complete signal?
• Anyone running a Pylontech or similar managed battery seeing the same behaviour?

It's not causing any real damage as far as I can tell, but it's annoying to see the solar wasted on a decent day, especially parked up and relying entirely on the panels. Worth noting my system was perfectly stable on 3.60.

Thinking about rolling back to the previous firmware until Victron push a fix, but wanted to check if anyone's found a workaround first — changed a setting, tweaked the DVCC limits, anything like that?

@OldSailor75 yes, seeing exactly this on my shepherd's hut system — SmartSolar 150/35 with a Fogstar Drift 200Ah, updated to 3.75 last week and now getting random zero-output dropouts lasting anywhere from 30 seconds to several minutes.

Worth checking a few things before rolling back:

• VE.Direct cable — 3.75 apparently tightened communication polling, so marginal cables that worked before are now causing disconnects
• Check your MPPT error log in the VRM portal; I'm seeing Error 17 (charger temperature sensor issue) appearing just before dropouts even though temps are fine
• Some users on the Victron Community forum are reporting this is specifically affecting units with older firmware on the MPPT itself — make sure the controller firmware is current, not just Venus OS

I've raised a ticket with Victron directly. Their UK support has been decent response time lately. Tempted to roll back to 3.70 in the meantime.

@OldSailor75 @LesWood78 — so it's not just me then! I was genuinely convinced a seagull had chewed through my panel wiring before I started digging into the firmware side of things 🐦

Quick question for you both — are your MPPTs dropping to zero completely, or just throttling down to some

@MarineFrank that seagull comment had me proper laughing — I've blamed birds for worse on my boat, genuinely.

Worth checking your Venus OS logs before anything else. On my setup (SmartSolar 150/45 charging a pair of Fogstar Drifts, also feeding my EV charging station via a Victron Multiplus), I traced a similar gremlin to the DVCC settings getting quietly reset after a firmware jump. The MPPT was basically arguing with itself over charge authority.

Head into Settings → DVCC on your Cerbo and double-check SVS and SCS are configured as you'd expect — a reset there can make the MPPT look completely dead when it's actually just confused about who's in charge.

Roll back to 3.60 if it's urgent, Victron's archive is still accessible. There's already a thread on the Victron Community forum with a few engineers keeping an eye on it.

@OldSailor75 same issue on my van conversion — SmartSolar 100/20 with a Fogstar Drift 100Ah, dropped to zero mid-afternoon on a gloriously sunny day which felt like a personal insult.

Did some digging and it seems Venus OS 3.75 introduced a bug around the DVCC charge coordination, particularly when the BMS and MPPT are having a disagreement about who's actually in charge. Basically the MPPT just... gives up.

Workaround that sorted mine: temporarily disabling DVCC, saving, then re-enabling it seemed to kick everything back into life. Not a fix, obviously — more like giving it a firm talking-to.

Victron community forum has a thread going, apparently a patch is in the works. I'd hold off rolling back to 3.74 unless you're comfortable with the process, it's a bit fiddly if your GX device is buried behind a dashboard like mine is.