How to change MPPT params in VC

Anyone managed to tweak the charge voltage params on a Victron MPPT when there's a BYD-style BMS already sitting in the driving seat via VictronConnect?

Running a garden office setup here — Fogstar Drift LiFePO4 cells with a SmartSolar MPPT 100/30 — and the BMS is communicating over the VE.Can network, which is great in theory, but it seems to have locked me out of manually adjusting absorption and float voltages in VC. Everything's greyed out like it's a museum exhibit.

I get why it does this — the BMS is supposed to be the authority on charge parameters — but Victron's own documentation suggests slightly different voltage figures to what the BMS is currently pushing, and I'd rather follow Victron's recommended settings for longevity rather than let the BMS run the show unchecked.

Specific questions:

• Is there any legitimate way to override or nudge the charge voltages when a BMS is active on the network, or is it genuinely hardcoded once that handshake happens?
• Has anyone used VEConfigure or the GX device to get around this, or does that path hit the same wall?
• Is the answer just "trust the BMS" and stop fussing?

Conscious this might be a "working as intended" situation, but given this is also my emergency backup for the house during outages, I'd like to actually understand what voltages are being applied rather than just hoping for the best.

Any wisdom from people who've wrestled with BMS-controlled MPPTs gratefully received — documentation links especially welcome if they exist somewhere sensible.

@RelayBuild classic two-cooks-in-the-kitchen scenario 😄

Worth knowing: when a BMS is talking DVCC to the system, Victron intentionally locks out manual charge voltage tweaks in VC. It's not a bug, it's the point — the BMS is meant to be the authority.

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@RelayBuild ooh this is basically the same headache I had on the narrowboat when I first set up DVCC with a Daly BMS — the MPPT params went greyed out in VictronConnect and I genuinely thought the app had glitched 😅

Quick question before you go poking around though — is your BMS actually capable of sending CVL/CCL/DCL properly? Because if it's only partially supported, you can end up in this weird halfway-house where DVCC thinks it's in control but isn't quite, and the MPPT just sits there confused.

Have you checked the GX device logs to see what charge voltage limit the BMS is actually broadcasting? Might be worth confirming that first before assuming the params need manual tweaking — sometimes the BMS is doing exactly the right thing and the greyed-out fields are actually a feature rather than a bug!

@RelayBuild curious whether you've actually tried overriding anything manually in VictronConnect while DVCC is active? On my setup I found the charge voltage field just goes grey and uneditable — the MPPT essentially defers entirely to whatever the BMS is broadcasting via the GX device.

What GX device are you running between the BMS and the MPPT? That's usually where the magic (or the frustration) happens. If the CVL coming from the BMS looks wrong, I'd be checking that first rather than trying to fight the MPPT directly.

Also worth double-checking your battery preset in VE.Configure — even with DVCC active, some parameters like absorption time limits can still be adjusted there depending on firmware version. What version is your MPPT on?

@RelayBuild yeah basically the MPPT's gone full "assistant manager" — thinks it's in charge, but the BMS is the actual gaffer upstairs sending down orders via DVCC 😄

In VictronConnect you'll still see the charge voltage fields, but they're greyed out for a reason — trying to edit them while DV