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24V travel trailer with 50A power and 400W solar wiring help please

socrbabe15

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California
I have a travel trailer that I am re-doing from scratch. I am planning a 24V system, with ~400W solar on the roof and likely the LiFePO4 solar rack batteries. I will start with one, but may consider 2. I'll be using a stand alone surge protector for incoming 110v power. We are not currently big electrical users, but that may change with time. For reference, in my old truck camper I would go off grid for a week with 3 people with a single car battery, no solar, though this is a 31' trailer, so has inherently more use required and my daughter is tied to her ipad now. Hoping to change that during camping trips.

I am looking for information on systems/wiring diagrams, and don't fully understand how all the components hook together, especially the incoming shore power. I think I have my head fully wrapped around the solar portion, but once the 50A 110 has to join it, I get confused. Do I need transfer switches? Where do things hook up? I do like the SunGoldPower 2000W Inverter but my goodness it uses a lot of power when not on standby (150W). I looked at the diagram on the web site and it's solar only, so doesn't help much. Will doesn't seem to have gone over anything similar other than the all in one systems.


I expect to only use one leg of the 50A power initially, as the other leg will be for a (not used or installed) 2nd A/C, in the bedroom. I plan to have both A/C units only available on shore power or generator. I plan to have 12v USB outlets everywhere, and sparse 110V outlets. We'll be using boat style circuit breakers instead of a fuse panel. I would prefer individual parts instead of an all-in-one, for customization, and in case of a component failure. Can anyone help with a general diagram or system setup? I can most likely modify it to suit once I understand where the big pieces and routing goes. I would like to get the required shore power parts in now as I do my rebuild, then I'll add the remaining (solar and battery) parts as my RV comes together in a year or so. Any help would be appreciated.
 
My 3000watt 24volt AIO was cheaper than just buying a pure sine wave inverter at 3000watts. In fact, I bought 3 of them, 2 more after using the first for one day.

I also have individual components 12v system. Some RV inverters like my progressive Dynamics inverter have built in transfer switch but are 12v only?

Wills diagram has the transfer switch on upper left. eTrailer sells stand alone RV transfer switches. The ATS he shows is not in his component list.: www.amazon.com/MOES-Controller-Automatic-Transfer-Switch

This transfer switch switches to shore power when batteries are low, cool if battery/solar is priority.

Uncertain as to how exactly to wire Sungoldpower in since it's a combination unit. Nice to be low frequency inverter I think but ads expense.

All a tradeoff, standby power consumption high.
 
For an RV with 50 amp shore power connection this is just about the best inverter/charger.
It appears to use shore power as priority, only using inverter when there is no shore power.

Opposite of my choice- use solar/battery and only shore power if battery is low, don't know what the OP desires.
 
It appears to use shore power as priority, only using inverter when there is no shore power.

Opposite of my choice- use solar/battery and only shore power if battery is low, don't know what the OP desires.
I would be surprised if it can't be configured to work in either mode.
@sunshine_eggo will know.
 
I would be surprised if it can't be configured to work in either mode.
@sunshine_eggo will know.
The website link you sent said :The MultiPlus switches to inverter operation when no AC source is available.

I looked at the datasheet but not manuals and didn't see any configuration mentioned. It would be nice if it was!

I have an RV inverter and it is shore mode priority also, and other RV offerings seem to prefer shore power and that negates my desire to use solar first.

I've not opened my inverter to see if I could switch it and tech support was not able to answer some of my other questions so I never asked the company.

Since I am not in the market I probably won't read the Victron manual to see if configuration can be changed. Although curiosity may compell me to know
 
I appreciate you finding that info for me. Just good to know that there are capacities and capabilities in case I do ever choose to look at victron or have someone asking questions so I can give more informed answer
I hope I have not lead you astray.
 
Do I need transfer switches?
You need 1, its built into the inverter/charger I linked earlier in the thread.
Where do things hook up?
Can't answer that yet.
We'll be using boat style circuit breakers instead of a fuse panel.
Doesn't your travel trailer have a legacy ac/dc distribution center.
I suggest to use that unless it doesn't meet your needs.
I would prefer individual parts instead of an all-in-one, for customization, and in case of a component failure.
The inverter/charger is a good place to make an exception to this rule.
The integration of the inverter, charger and automatic transfer switch allows much better functionality than discrete components.
Can anyone help with a general diagram or system setup?
I would be glad to.
A good design starts with well defined requirements.
This is best done as an interactive process.
We can do that here in this thread.
I can most likely modify it to suit once I understand where the big pieces and routing goes. I would like to get the required shore power parts in now as I do my rebuild, then I'll add the remaining (solar and battery) parts as my RV comes together in a year or so. Any help would be appreciated.
I like that idea.
Do you have access to a 50 amp shore power supply?
 
I am looking for information on systems/wiring diagrams, and don't fully understand how all the components hook together, especially the incoming shore power. I think I have my head fully wrapped around the solar portion, but once the 50A 110 has to join it, I get confused.
In my signature block I have a link to my build. Part 1 is the 12 volt, and part 2 is the 24 volt upgrade.
Do I need transfer switches?
Your system has one, but I don’t have one. When on solar and Boondocking, the inverter is hard wired with a 30 amp RV plug, and I plug that in shore power. When in a pay per night campsite with full hookups, I plug the campsites shore power in.
I do like the SunGoldPower 2000W Inverter but my goodness it uses a lot of power when not on standby (150W). I looked at the diagram on the web site and it's solar only, so doesn't help much. Will doesn't seem to have gone over anything similar other than the all in one systems.
I don’t like all in one systems for an RV for this reason of high idle draw. I use Samlex inverters and their 24 volt, 2000 watt inverter is a 20 watt draw. This still adds up.

I have 12 hours a day I don’t use the inverter, so I can shut the inverter off. Also, I may come back from a trip a but depleted and want to charge and can’t get back to it for a week or two. That’s a lot of idle draw for an all in one, and a few cloudy days could drain it. Panel space on the roof is valuable real estate in an RV.
 
I'm going to have to measure what my all-in-ones actually consume at idle. I would like to know. But when I see people recommend an inverter standalone unit that cost more than my all-in-one cost it makes me want to roll my eyes and of course they throw out the tried and true all all in one inverters have such a high idle capacity that by the time you fall asleep your batteries will be dead.

Hopefully someone finds what I just said slightly humorous. Because by the time I buy somebody's really expensive standalone inverter. A halfway is decent mppt. And some kind of charger. And maybe even another hundred dollars for a transfer switch that allows them to use shore power along with battery and solar

Anyway by the time I had all of this up I think I can buy at least 100 amps more of battery power and get another solar panel and that battery will easily fit in the space I have saved by having an all-in-one unit. And yes I have my eggs in one basket so I have spare inverter that's a standalone spare solar charge controller even wires but I am taking away from this thread

I should probably just delete this reply after I post it because I don't see a good way to just cancel out
 
You'd made a good point

I'm going to have to measure what my all-in-ones actually consume at idle. I would like to know. But when I see people recommend an inverter standalone unit that cost more than my all-in-one cost it makes me want to roll my eyes and of course they throw out the tried and true all all in one inverters have such a high idle capacity that by the time you fall asleep your batteries will be dead.

Hopefully someone finds what I just said slightly humorous. Because by the time I buy somebody's really expensive standalone inverter. A halfway is decent mppt. And some kind of charger. And maybe even another hundred dollars for a transfer switch that allows them to use shore power along with battery and solar

Anyway by the time I had all of this up I think I can buy at least 100 amps more of battery power and get another solar panel and that battery will easily fit in the space I have saved by having an all-in-one unit. And yes I have my eggs in one basket so I have spare inverter that's a standalone spare solar charge controller even wires but I am taking away from this thread

I should probably just delete this reply after I post it because I don't see a good way to just cancel out
 
You need 1, its built into the inverter/charger I linked earlier in the thread.

Can't answer that yet.

Doesn't your travel trailer have a legacy ac/dc distribution center.
I suggest to use that unless it doesn't meet your needs.

The inverter/charger is a good place to make an exception to this rule.
The integration of the inverter, charger and automatic transfer switch allows much better functionality than discrete components.

I would be glad to.
A good design starts with well defined requirements.
This is best done as an interactive process.
We can do that here in this thread.

I like that idea.
Do you have access to a 50 amp shore power supply?

My trailer has nothing. It's a 1975 Airstream that has been gutted. I'm starting from scratch. I'm going to rebuild the rotten floor before my next trip (to a plug in campsite), and I'll need to start putting the necessary things back in to have phone charging and basics. I have a Progressive Dynamics converter (free) I will use to convert 110v to 12v so I can use the fridge, and I may charge phones with a 12v USB outlet off that. But otherwise planning the long game and looking to see how I can break it up into affordable stages. My house has a 30A RV plug and I have a 30A to 50A dogbone. I won't need to test the 50A leg right away because it's a "future use" item, for adding a 2nd A/C unit in the back.

I am looking up that Victron unit, and I hadn't seen it on their website yet, and I have to admit that may be exactly what we need. I do need to look more into their version of 2 120v legs, as it looks like they will switch both legs internally to 120v when the inverter comes on, and if that changes the phase they are in, can ruin the A/C unit. I have no 240V loads planned, however tempting it is to bring my welder. I'll download their manual and go from there once I understand it better. Thank you for finding how to change the A/C vs 12v priority, I haven't decided which I'll prefer when it is parked at home.
 
I do need to look more into their version of 2 120v legs, as it looks like they will switch both legs internally to 120v when the inverter comes on, and if that changes the phase they are in, can ruin the A/C unit.
I'm not sure but if anyone would handle the phase change properly it would be Victron.
@HighTechLab do you know how the MP2 2x120 handles the phase change when 50amp shore power goes away?
 
I am not in the RV industry but I do believe that a 50 amp RV plug is not dual phase that it is just too 120 legs am I right or wrong?

At least I don't think anything in these RVs is actually 220 volt

If they're not then honestly all you need is two of any kind of inverter. Because you keep the legs separate they never connect you never put a220 appliance.

I believe everything is either 120 or 12 volt.

If I'm right then there's no need for inverters that synchronize and put out properly phased voltage.
 
I am not in the RV industry but I do believe that a 50 amp RV plug is not dual phase that it is just too 120 legs am I right or wrong?
It is split phase.
You could plug a 240VAC device in if you wanted to.
 
Yeah that would be handy if you wanted some kind of heavy duty like clothes dryer that's electric

My girlfriend's travel trailer is only a 30 amp so it's only 120 volt
 
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