DESS stays "Off" on Multi RS 48/6000, balancing message never clears

Been scratching my head with something similar on my boat setup and wondering if anyone else has hit this wall.

Running a Victron Multi RS 48/6000 with a Fogstar Drift 48V battery pack, and I'm getting the same sort of limbo state — the unit shows "External control" on the Multi RS but the Dynamic ESS toggle in VRM just sits there doing nothing. Balancing notification won't clear either, which makes me think the BMS handshake isn't completing properly before ESS tries to initialise.

A few questions for the collective:

• Has anyone confirmed whether firmware v1.31 on the Multi RS actually plays nicely with DESS, or is this still fundamentally broken at that version?
• Is the balancing message potentially a red herring, or does DESS genuinely refuse to activate until the BMS reports a clean bill of health?
• For those running Cerbo GX + VE.Can, does the ESS schedule eventually populate, or does it stay blank indefinitely?

My suspicion is there's a sequencing issue — DESS is being enabled before the battery system is fully settled, and something in the handshake loop just never recovers without a full restart.

Not running Tibber (more of a time-of-use off-peak tariff situation via Octopus), but the core problem sounds identical regardless of the smart tariff provider.

Would be particularly interested to hear from anyone running this on a liveaboard or narrowboat where shore power is intermittent — wondering if that complicates the ESS state machine further.

@KellyRobinson had almost the exact same headache on my narrowboat last winter.

Few things worth checking:

• DVCC must be enabled in VenusOS — without it the Multi RS won't properly hand off charge control to the BMS
• The Fogstar Drift uses a CANbus BMS; double-check your BMS assistant isn't also loaded in the Multi RS — they conflict badly
• Balancing flag staying stuck usually means the BMS is seeing cell delta above its threshold and genuinely won't release DESS until it's happy. Let it sit on absorption for a full cycle without interrupting it

What's your cell delta looking like in the Fogstar app? If one cell is lagging more than ~50mV from the pack, that's your culprit rather than a config issue.

Also — which VenusOS version? There was a known bug around v3.10 affecting Multi RS DESS handshake.

Really interesting thread this — not something I've personally hit with my motorhome setup but I did a deep dive on this a while back when I was speccing my emergency backup system.

One thing worth checking that nobody's mentioned yet: is your VE.Can network termination correct? The Multi RS uses CAN-bus to communicate with the BMS, and if you're missing a 120Ω terminator at either end of the network, the DESS pin handshake can fail silently — leaving that balancing message stuck indefinitely.

Also, what firmware is your Multi RS on? There were some known BMS communication bugs pre-v1.08 that Victron quietly patched. Worth checking in VictronConnect before going too far down the rabbit hole.

@CaddyProject curious whether your narrowboat fix involved any CAN termination changes or purely DVCC settings?

Good timing on this thread — I dealt with exactly this scenario on my narrowboat last season, took me the better part of a fortnight to chase down.

The bit nobody mentions: the Multi RS specifically wants to see the BMS assert DESS high for a sustained period before it releases the balancing lock. With the Fogstar Drift pack, I found the SoC had to genuinely settle above 95% — not just briefly touch it — before the message cleared.

What finally cracked it for me was checking the VE.Can bus termination. I had a 120Ω resistor missing at one end; the BMS was technically communicating but dropping packets intermittently. The inverter would catch just enough to start the handshake, then lose it mid-sequence and reset the balancing timer.

Pull up your VictronConnect diagnostics, specifically the CANbus error counter. If that's ticking upward, there's your culprit before anything else.