Victron MultiPlus-II 48/6k5/100-50 only charging at 60amp (not 100amp)

Been scratching my head over this one and wondering if anyone else has run into the same issue.

Upgraded my system in the motorhome to the Victron MultiPlus-II 48/6k5/100-50 a couple of months back, partly because I wanted to push proper charging speeds when I'm hooked up on site or using a timed charge overnight. The 100A charging capability was a big selling point for me — should knock a decent chunk off charging time compared to my old setup.

Problem is, I'm only seeing around 60A actual charge current in VictronConnect, no matter what I do. I've checked the charge current limit in the settings and it's definitely set to 100A. The input current limit on the AC side is set to 16A (standard UK campsite hookup), so I don't think that's artificially throttling it — the maths should still allow for more than 60A on the DC side.

A few things I'm wondering:

• Could this be a temperature derating issue? The unit does get warm in the locker.
• Is there a firmware version that's known to cause this? I updated to the latest before commissioning.
• Could battery settings in VEConfigure be capping it without me realising?

My battery bank is 4x Fogstar Drift 12V 200Ah wired in series for 48V, so capacity shouldn't be the limiting factor.

Has anyone else seen their MultiPlus-II throttle back like this? Would love to know if there's a straightforward fix or if this is actually normal behaviour under certain conditions.

@MuddyMaker had almost the exact same head-scratch with my van build last year.

Worth checking a few things before you go down the rabbit hole:

Check your AC input current limit first. The MultiPlus-II will throttle charge current to protect the incoming supply. If you're on a 16A hookup and you've got loads running simultaneously, Victron's PowerAssist will quietly rob your charge amps.

Also — VEConfigure is your friend here. Connect via MK3-USB and check what the actual charger current limit is set to in the config. From factory or a previous installer, it's sometimes deliberately capped lower than the hardware maximum.

Finally, what battery BMS are you running? If it's communicating via DVCC over VE.Can or VE.Bus Smart Dongle, the BMS itself might be requesting reduced current. Fogstar Drift cells in particular can be conservative when they're not fully commissioned.

What's your battery setup?

@MuddyMaker one thing nobody's mentioned yet — check your AC input current limit in VictronConnect. The MultiPlus-II will back off the charge current automatically if it thinks the incoming supply can't handle the load. If you've got the AC input limiter set low (say, 16A on a 230V supply), it'll throttle the charger to protect the shore power feed, which works out to roughly 3.5kW — way less than the full 100A charge capability on 48V.

Also worth pulling up the VEConfigure settings and checking the Charger tab specifically — there's a separate maximum charge current field in there that overrides the front panel. Easy to miss if you've imported a config file from an older unit.

Mine did something similar after a firmware update reset a couple of values silently. Always worth doing a full config export before and after updates.

@MuddyMaker here's the bit that catches people out — the 100A charge current is the maximum, but the MultiPlus-II will throttle back aggressively if it's thermally dithering or if your battery BMS is quietly capping the charge current via DVCC in VRM/VictronConnect.

Had this exact scenario with my 280Ah Fogstar Drift cells last winter. The BMS was whispering "60A max" through the VE.Bus and the MultiPlus just... obliged. Politely. Without telling me.

Check your DVCC settings in VictronConnect — specifically whether "Limit charge current" is enabled and what value it's set to. Also worth looking at the BMS charge current limit in real-time on the VRM dashboard if you've got a GX device.

@WheresMeWires makes a fair point about AC input limiting too — both can stack against you simultaneously.

Good point from @LiFePO4Nerd about that being a maximum figure — worth adding that your battery BMS could be throttling it too.

Had this exact situation with my static caravan setup running Fogstar Drift 48V cells. The BMS was requesting a lower charge current via DVCC in VictronConnect, and I'd completely forgotten I'd set a conservative limit during initial commissioning and never changed it.

Worth checking:

• DVCC settings in VictronConnect — is "limit charge current" ticked and set low?
• What's your BMS actually requesting via the comms cable (if you have one)?
• Battery temp — does your BMS back off charging current in cold conditions?

What batteries are you running? That'd narrow it down considerably. If they're not communicating with the MultiPlus at all, that changes the diagnostic approach entirely.