I have been running my [
MultiPlus-II 2x120V for a few years but recently added 6000w of solar to my rv and a eg4 6000xp to convert it. the 6000 feeds the MultiPlus-II 2x120V through a 50 amp plug when boondocking and the 6000 is out of the system completly when pluged into shore power. the problem comes when the sun goes down. if running both ac’s i need about 2400 watts and the solar does this till preetty dark but the 2x120 ignors power limits on leg 2.
Here is the scenario that kills me. 2 ac’s running and a limit set to 9.3 amps (lowest the Victron will go. it pulls 1100 watts from leg 1 and another 2400 from leg 2, running my ac’s and bulk charging the 12v system…why does it use unlimited power from leg 2? This seems dangerous with a dogbone on a 15-amp service. I have enough solar to run both ACs, but not if the charger is running full out. 12V system is always above 95% as it’s 1100Ah and only runs 12V loads.
Is this becuase the 6000xp is a true 240 center tap? does it see a dogbone as 2 in phase connections so it knows its only one? still seems off that if I plugged in 240v 50 amp shore power and said only pull 9.3 amps, it would melt the system down if leg 2 wanted 50 amps one wires that are not rated for it. .
I’m not sure what the 6000xp is putting out, but from your 2nd paragraph it must be split phase. If you have a split phase input, you need to make sure whatever cables / adapters you are using are rated for the full loads you have on L2 in the rv. This is a very non-standard hookup, so you need to make sure yourself. There should be NO scenario where you have a 15A rated dogbone in an split phase input to the 2x120.
The 2x120, if it is connected to a split phase input, connects L2 directly from the input to the output. L1 input is the line that will power the charger and receive power assist from the inverter if needed. L1 is also the only line that uses the set input current limit. L2 does NOT respect the input current limit. It cannot. It passes directly to the L2 output from an internal relay.
When connected to single phase input, the L2 input is essentially turned off. It uses only the L1 input and passes that to the L1 AND L2 outputs. In this case, since all power in is from the L1 input, the current limit is respected and both L1/L2 loads in the RV will get power assist if needed.
The only split phase plug you should see is the standard 50A 14-50 rv plug. Or, if you’re powering from something specific like a 240v/split phase generator, or the 6000xp in your case, THAT plug and any adapter and cables used should be rated for the full draw capable from the RV and charger on that line.
Re-reading, I think I see your issue a little more clear.
First, on the 15 amp dogbone. You’ll only ever use that on a single phase service, so there is no L2 input to draw from. All power will come into L1 and the the input current limit will be followed.
2nd, RE: your situation where you can power 2 A/C units, but not both units and the charger. This can only happen if your solar is feeding split phase to the inverter. You have this issue because the inverter charger is on L1 and you have both A/Cs on L2. The easiest fix would be just to swap the L1/L2 lines running from the inverter to your panel. You want the side of the panel with the A/C units to be powered off L1 from the inverter.
Or, you could just move the breaker for one of your A/C’s to the other side of the panel. Put one on L1 and the other on L2. Even just the 1 A/C on L1 will be enough to stop the charger from running with a 9.2A input current limit.
This way, the charger will still work if it can, but running the A/C’s will turn it off and it’ll start power assisting for loads over your input current limit.
the AC’s are on differnt legs. I have swaped the breakers as the bigger one was on leg1 and it evened out the load a bit to have the bigger AC on leg2.
the 6000xp does do a split phase.
The dogbone issue is that for a 50-amp RV, a dogbone takes the single input and puts it on both leg 1 and 2. 50-amp RVs rarely actually have anything 240v. Mine has nothing. However, if you just hook up leg 1, half of the stuff wouldn’t work. Thus the dogbone puts the same power to both legs. My issue is if leg2 cant be controled I am basicly trying to pull 15 amps through leg 1 and 30 amps through leg2 on a 15-amp circuit.
My system is a bit custom, but only untill someone makes a real RV style inverter. One of the coolest things the 120vx2 does is bridges leg1 and 2 if only leg1 is powered. My dream would be to have a 7500va inverter on 48v with 10k solar chargers and a small 12v charger. Every RV would use one. It wouldn’t hurt to make it double online conversion, either, so you don’t have to worry about input power.
I am in the process of adding an Ekrano, so I can add a one-touch button to turn off charging. wish they had this in the app. an inverter without charging mode should be easy.