so long story short - on my RV I switched to a Quattro 24/8000/200-2x100 and ended up with minimum current limit @10A. A lot of camping sites are still offering only 4A or 6A here so I’m trying to see if I can find alternatives on how to just charge batteries.
To make it clear I don’t need shore to run my loads as I have 2Kwp of Solar and 1200ah of batteries. I would still be quite happy to just charge @4A as I have hours during the day when I’m not really consuming such.
Is there any way so I can achieve such automatically? I’m good with any proposal, using modbus, signalk, node-red whatever?
As of now the only thing I can come up with is using a shelly (or any smart relay) on the shore connection so that I can at least disconnect (remotely) when going over the maximum current set.
Any ideas? personally this lead me to think it would have been better to have a dedicated charger and a separate inverter.
@guystewart apologies for calling you directly but just reading some inputs on other threads for similar ask - do you have ideas for my use case? thanks
the problem I see with the proposal is that I don’t think a small charger can address the need. For 4A/6A charging (but also for lack of bigger space at this point) I would look at a Smart IP43 Charger (that given the VE.Direct port would be controllable by the Cerbo). However as far as I remember I don’t think you can set a charging current on it, you can only monitor its state
ahhh I see the logic ok - well it’s better than nothing
one more questione please as I have lithium (victron) batteries and not sure how the system will behave at this point if I switch off charger of the quattro and leave in inverter only. Today I’m on BMS v1 but I’m planning to upgrade to BMS v2 and will need to enable DVCC: just need to think about if disabling the quattro charger might inhibit charging from Solar MPPT (victron as well)?
according to specs the 24v version charge max at 25A, so 600w or 2.6A @230v … which is better than nothing but very very low considering that the majority of camps with low amp electricity is probably 6A rather 4A.
You could turn off PowerAssist in the inverter if your 8kVA inverter is all the power you would ever need. But, if you sometimes want PowerAssist, then you could build a flow in NodeRed that will allow you to turn on/off PowerAssist w/o having to use VEconfigure or VictronConnect every time you want to turn PowerAssist on/off. I’ve been meaning to do this in my camper but just haven’t gotten around to it yet. But, I did verify it’s possible with NodeRed
ah that’s the first thing i implemented in my management app (home assistant via modbus) and I can switch it on and off in a moment.
The problem is that, based on my understanding of the situation, once it’s disabled you wont be able to have any load above 6A (in example). I haven’t yet tried but based on what I read any load above 6A will end in a overload ? do you have any experience to confirm?
### Without PowerAssist
What would happen in this exact scenario *without* PowerAssist? You would have to disconnect from the input source and go back to operating off the inverter only. If you feed the inverter with, say, 3000 watts but you need 4,000 watts, well, you have to disconnect from the source, the generator, or the shore power connection. Your other option is to kill all the loads, such as the air conditioner, and charge those batteries. Without power assistance, you may also have to go into your charger settings and reduce the charge current so you're not overloading your small input source.
In a system where you don’t have the ability to supply over twice the inverter size, you really can't charge the batteries and run the loads at the same time. You would end up doing things like backing off the charging current. **PowerAssist is what allows you to bring in a smaller or right-sized energy source - or plug in where no one has plugged in before successfully - while maintaining total power output.**
I understand that I could use the shore until my AC load won’t exceed its capabilities (let’s say 6A in my above example). If that happens to avoid tripping the breaker I will have to disconnect the loads.
@stefano I think your understanding is correct. I wasn’t 100% certain so I didn’t respond to your question on Feb 16th. The guys at Intelligent Controls know their stuff so I accept their explanation without reservation. In your scenario, I would leave PowerAssist turned on and use a separate battery charger. You could connect it to AC2-Out so that it’s only powered by shore power (never inverter) and would be subject to the AC input current limit. This way you wouldn’t need to run a separate cord to the camp ground pedestal.
I have a similar situation in my camper. I have a Victron 12/1200 inverter in the back of my truck that I want to use to charge batteries in my camping trailer while I’m traveling. But, the 24/5000 inverter has a minimum AC current input limit of 10.9A at 120V. That exceeds the continuous output rating of my 12/1200 in the truck. So, I either need to disable PowerAssist when traveling and re-enable it when I set up camp if I have shore power OR install a separate battery charger in the trailer to be powered from my 12/1200 in the truck when traveling. The easiest approach would be the separate battery charger, but the more nerdy approach would be to use Node-Red to turn PowerAssist on/off from a dashboard. We’ll see which one I pick based on how much “free” time I have
@OGPS Thanks a lot for confirming my thoughts - having a separate charger is not an option unfortunately as I would need a Skylla and I don’t have space left for it.
I had this thought in trying to address somehow the case without any equipment and just in software:
suppose max input current need to be 6A
run an automation that constantly check current draw (in my case I will use HA rather than node-red)
if output loads are above 6A I disable my quattro charger and stay in invert only.
as soon as my load run below 6A I disable power assist, lower input current to 6A and enable charger.
If current draws goes down, then I don’t see issues. If the current draw increase most probably I won’t have enough time to increase input current to support such without having my quattro going into overload: do you know if that’s immediate?
