I am not sure what to make of this. This happens often when a big load (geyser) in the house comes on, and the MPII 3000VA is running flat out to try and keep the house consumption as low as possible.
Yes, it is just a warning, but it is annoying 
Is your geyser wired as all other essential loads?
No - the geyser is “before” the MPII, on the non-essentials db (with other things like the oven, some of kitchen plugs etc.). This happens when the MPII is trying to get the grid feed-in down to as low as possible - that’s also why you see “-2422W” on the screenshot above, as it is feeding back into AC Input L1.
What battery do you have and are you using a cable to talk to the BMS?
Maybe gives us a quick rundown of the system (GX, etc?)
- Multiplus II
- 150/35 MPPT with 4x 405w panels
- Venus GX
- BYD 5kWh battery, connected with proper cable to Venus GX
DB split inside house, to essentials and non-essentials loads. Only non-essentials running on AC Out. The system is setup with ESS, but no feedback to grid.
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Initially thought a battery message but doesn’t look like the case…
Have you tried bypassing the BYD monitoring box and going from battery to GX directly?
I thought the GX can communicate directly?
As far as I have it it has to go via the white BYD BMU.
See also here: Victron & BYD [Victron Energy]
I don’t think there is something wrong in the config, or how it is wired - the MPII is overperforming in ESS, and somehow overshoots into an L1 warning. I think
“-2422W” … shot in the dark … 4 x 405w panels = 1296w, the 80% efficiency deducted.
Yes, the diff must come from the battery, but, what if you limit the inverter to 1000w, just to see if the message goes away when grid-tied?
Process of elimination if you want … subject to a more in-depth analysis by other experts of the actual data.
What is the firmware on the MPII?
I know there was an update that talks about the overload error…
All devices were recently updated - the MPII is on “500”.
It seems like the software is just telling you know the inverter is approaching a state of overload. Could be temp related. Then it might derate, cools down, ramp up again, etc. Just a guess.
I agree that while grid-tied, you’d assume the inverter should derate before bothering you with that info, but perhaps there’s a bug somewhere. Seems harmless though, so I wouldn’t spend too much time on it were I you.
I agree - just a warning, nothing serious. But, being in the software field myself, this is curious to me!
The 3kVA MultiPlus-II can do 2400W at 25 degrees. As it heats up it will derate and you’ll have less and less available output, so I agree with @jykenmynie here.
I’m guessing it’s also pretty warm where you are, so higher ambient temp (based on the fact that it happened at midday) along with the 2400+W load already on the Multi is most likely causing it to slightly derate causing the overload warning. I think.
I guess it’s interesting that it’s giving overload warnings from load in front of the inverter. Can you maybe post “System - AC Consumption” and “System - Critical Loads” screenshots from around that time (see if you can get it down to show 1 minute intervals). I doubt it’ll show much as the warnings clear after a couple of seconds which I’m guessing is the Multi responding to itself and slowly tapping off.
I see both the occasional overload AND temperature warning while grid-tied. BUT… I think it has to do with the cabinet my Multi lives in. It runs hot. I measured it and it typically runs around 47°C (measured on the outside of the aluminium case, where the heatsinks bolt to the case). Our hot summers is definitely not helping. At least, that’s what I think is going on.
I think it must be temperature related. We switched the geyser on a while ago, and no warnings yet, whilst yesterday at 12:00 it was warning a lot.
With Jykenmynie re the temp derating … I remembered why I sold my 3kva.
On hot summer days, it dropped to like 1.7kw max.
It is not derating at all that I can see - it soldiers on at around 2450W all the time.