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Author Topic: Solar/house/vehicle/shore power interconnections  (Read 696 times)


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Solar/house/vehicle/shore power interconnections
« on: January 11, 2017, 02:54:57 PM »
I'm trying to figure out how to interconnect the various power systems I plan on making available in my upcoming van conversion. Here are the basic systems I'm working with:

1) 400 watt PV solar array into a charge controller into 2 12V AGM batteries (house) powering all 12V accessories and an inverter to supply 120V outlets
2) Vehicle alternator and battery (12V) only used for starting the vehicle
3) External connection to shore power through a 120V or 240V connection (I only need 120V and understand how to get that from 240V)

I understand how each of those work independently, but I'd like to connect things in such a way as to accomplish all the following things:

1) I'd like to trickle charge the vehicle battery from the solar system (automatically when the vehicle is not running).
2) I'd like to be able to start the vehicle using the solar batteries if necessary (a manual switch is fine).
3) I'd like the 120V outlets to be shore powered when shore power is connected, otherwise they are powered by the inverter from the solar system. I'd like the switch-over to be automatic when shore power is plugged in, but I'd settle for a manual switch.
4) I'd like to charge the solar batteries from shore power if the PV array isn't producing enough juice. Again, I'd like this to be automatic, if possible, but could be by manual switch.
5) Assuming 4 is happening, it would also be nice if the vehicle battery were being trickle charged from shore power too.

How would I make the interconnections between the systems to allow all this?

I'm pretty handy electrically, but I'm having a hard time coming up with a workable solution. Any suggestions would be appreciated.



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Re: Solar/house/vehicle/shore power interconnections
« Reply #1 on: January 11, 2017, 05:19:13 PM »
Welcome to the site! Short answer- Google "Jack Mayer". You can learn a lot on his site. Pretty much everything you want is feasible.
I know you believe you understand what you think I said,
But I am not sure you realize what you heard is not what I meant

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Re: Solar/house/vehicle/shore power interconnections
« Reply #2 on: January 11, 2017, 07:43:37 PM »
Oh, it's not like your boy here didn't already figure out the HARDEST part of what you're asking, after many said it was impossible.....

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Re: Solar/house/vehicle/shore power interconnections
« Reply #3 on: January 14, 2017, 12:27:53 PM »
Thanks for all the info. Jack Mayer's site has a ton of info and provided some of the keys to the puzzle, as did supermanotorious.

The piece no one mentioned was a battery separator. Specifically, a Sure Power 1315-200, which will magically allow the alternator to charge the house batteries, allow the house batteries to start the vehicle, and allow the solar system to charge the vehicle.

I've attached a diagram of the current plan. I'm missing some fuses/breakers, but that's the basic idea.