Diesel generator passthrough and charging issues with Multiplus ii

DIY
, ,
1

I have a Hyundai dhy8000selr (this one) which mostly works great. Starts fine, runs well and reports a pretty consistent 50-53hz (as per the display at least).

I use it primarily to charge my off-grid home batteries (2x48v Fogstar 16.1kWh ) via a Multiplus ii 48/8000 when the solar can’t keep up.

However, when it’s running (and the Multiplus switches to charging/passthrough mode) I have a few issues:

* Washing machine won’t work (just beeps some error of some sort)
* Ecoflow Delta 2 won’t charge
* Multiplus ii charger is fine in bulk but when nearing 90%+ SOC it doesn’t seem to like absorbtion/float charging and starts frequently switching between charging and inverting (i.e. disconnecting the genny)

Several other electrical devices run fine (including lights, water pump, fridge/freezer and internet devices).

Might converting the genny from a floating earth to bonded help with these? I see similar issue in the archived forum (Multiplus II 48/8000 issues charging from generator - VictronEnergy) which suggests this might be the case but I’d value any other input before I go this route, if anyone has any advice?

2

I have pretty much the same setup as you with the Hyundai DHY8000SELR, multiplus ii GX 24/3000 and 2 x 24V Fogstar batteries.

I did see the same issues you describe with a washing machine throwing wobblies on generator with the previous old style Multiplus (now relegated to the shed backup system as it cannot be updated further) but the new Multiplus ii seems fine. It is set for weak AC and firmware updated to v556. There is newer v557, but seems ok as is, so I haven’t bothered updating to that.

Earths are floating.

Hope that helps

3

That’s interesting, thanks. Mine’s on v508 so maybe I should explore an update. My setup has an earth, though the genny is floating hence thinking it might be the issue. I’m fairly sure the issue is the generator as I don’t think the multiplus is doing anything in pass-through mode other than charging. I also have weak ac set though I’ve read conflicting reports of it being necessary with this generator.