Help with solar install

[Hetken1]

Hello all,
Finally have my 2005 Lexington in my driveway undergoing big changes.In the quest for more free floor space: and to remove the rugs
--Cut down the size of the table area to become a 30” bed
--Removed the couch and will replace it with a 30” fixed bed that will have my solar battery bank in the front section and sliding door storage to the rear, to hstore all our bedding

Next will be to remove the shower and toilet and turn the “bath room” into a wet bath. The compostable toilet will be where the shower was and the floor space where the toilet was will have a 24x24 shower base. Now there will be nice space in front of the vanity and the new toilet. The black tank (which has never been used will become an extended gray tank.

Of course I will post photos soon

Dilemma::
I will soon install three solar panels on the roof with all the appropriate controls BUT do not know how to integrate the existing existing two battery (house batteries) with the converter (if I can use the same) and blend it into the 450amp hour (@50%) solar system. I would be happy to pay a person to work with me but can not find anyone near Yonkers NY.
Thoughts and idea please !!
Ken

[JLeising]

I just simply went panel-to-controller, controller-to-battery bank. Converter, as connected by factory, has done just fine at reading the batteries and properly charging. I did include a switch and an inline fuse between the batteries and the controller. I have a 100 Watt Renogy panel with their PWM controller.

[Hetken1]

Thanks for the reply.
I will be installing 3, 160watt Renogy panels and 6, 6v, 225ah batteries.
Im wondering if and how I should use the existing "house battery" set up for the solar system.

Another question is how do I use my generator to charge my solar batteries when needed?
Ken

[formerFR]

Solar simply is wired from it’s solar Controller to your house batteries - no need for other batteries or to have anything to do with your Converter.

[formerFR]

Are you saying that you’re installing six new batteries that will not be connected to your current house batteries? If so, how do you propose to have your 12 V systems in your RV connected to these new batteries? Sounds to me like you would be better off to combine all six new batteries and your current house batteries in series and parallel.

The solar panels would really just be recharging your batteries, they don’t go directly to the converter, or directly to any of your 12 V items in your RV, but only serve to charge batteries ...

[formerFR]

also, if you tie in all the batteries together, they will all be charged by the converter/charger when the generator is running... do you also have an inverter?

[Hetken1]

Thanks all,
The two existing
house batteries are under the floor and are small acid batts. I would like to replace them with the 6/(maybe8), 6v, 225 ah, AMG batteries I will be installing. My question is can I simply; eliminate the existing batts and hook the new battery bank up to the "existing" wires? and if so, would the new battery bank be charged while driving and when the generator is running.
I will be installing all the controls and monitors (inverter/battery charge controller/shunt/temp gauge/ etc also
Ken

[formerFR]

certainly, youre just enlarging your battery bank

and yes, charging should come from Shore or Generator, and MAYBE the Alternator, if its wired for that - of course, your new Inverter/Charger should be sized to handle that

[SlowrideHD]

Sounds to me as if you have a lot of reading and research to do before tackling that change. Although not hard to do, if not done correctly it can be a disaster. For instance, if you want to use your new six battery bank to feed into your existing 12v system, the bank will have to be wired in a 2S3P configuration and will require some very large gauge wires. The same may apply to your three PV panels. Are you going to hook them in series for higher voltage and smaller wire size (if one panel is shaded in series they all drop in output). Or will you have them in parallel to boost amp output and keep it around 30v to your charge controller? If so, you will need big cables but the advantage is that if one panel fails or if one panel is shaded, it won't affect the other two. What sort of inverter are you planning to run to make all this battery power useful? It would be a waste to have that many batteries just feeding into your 12v system.

[Hetken1]

Thanks.
parallel will be the hood up. I have spent countless hours trying to put this together, which is why I am asking the question. I have been a GC for 40+ years and can answer "any" question you have regarding your house.
This questioning I present is because I am not sure and there is no "professional help" around here. I Googled "2S3P configuration only to fine too many offerings that only led to more questions.
Ken

[JLeising]

2S = two batteries in series. As you are using 6 volt batteries, two are needed in series to get twelve volts.
3P is three in parallel. As you intend to use 6 six volt batteries, you will need to parallel wire three sets of two batteries in series. Each set of two in series acts like a twelve volt battery; wiring these three “twelve volt” batteries in parallel results in one high capacity 12 volt battery.

[jimmoore13]

I confess I'm not clear on your intentions. Observations:

• Your solar charge controller connects straight to your battery bank (in parallel with the converter/charger) - no special connection is required;
• It's my understanding that it's unwise to mix battery types. If, for example, you intend to introduce new AGM or LiFe batteries into the system, do NOT run them in parallel with existing (old) flooded cell lead/acid batteries. Things won't work out well;
• It's also unwise to mix old and new batteries. In a simple illustration, it's not a good idea to mix a 4 year old group 24 (in good shape) with a brand new group 24 (12 volt battery). One should install two new batteries of the same type and size, or one will "prey" on the other;
• Your existing converter/charger should be connected to your new battery bank just as it was to the old battery bank;
• Above all, if you intend to introduce "exotic" batteries into your system, ensure that both your converter/charger and your solar charge controller are compatible with your battery type. One size definitely does not fit all, and the factory installation (and many solar charge controllers) are designed with flooded cell lead/acid batteries in mind.

I don't know if any of that was helpful, but hopefully so.

[Philkaty]

following

[SlowrideHD]

Originally Posted by JLeising

2S = two batteries in series. As you are using 6 volt batteries, two are needed in series to get twelve volts.
3P is three in parallel. As you intend to use 6 six volt batteries, you will need to parallel wire three sets of two batteries in series. Each set of two in series acts like a twelve volt battery; wiring these three “twelve volt” batteries in parallel results in one high capacity 12 volt battery.

Thanks for getting back to him with that answer. I made the assumption he was familiar with the wiring terminology...my bad. Everybody has to learn, no one is born with all the answers.

One thing...when connecting all your system, and again I am assuming that you are going to use an MPPT charge controller, make sure you hook your charge controller to your completed battery bank so that it can "see" the voltage configuration, prior to connecting your PV panels to the charge controller.

[Hetken1]

Hi, I do understand wiring and yes will be using a smart controller. My basic question was can I just remove the existing small acid batteries and hook up my new battery bank to the existing battery cables. And in doing so the new battery bank will address the RV as before. If so I assume the batteries will be charges by the running of the engine and by the generator--of course by the solar array also.
Ken

[PSU Turf]

Connect the new battery bank to the existing cables. Then follow the instructions for attaching your solar charge controller to the batteries. You will now have two electrical sources for charging your batteries (3 if you count trickle charge from vehicle engine). If you happen to be plugged into shore power on a sunny day the converter and solar charge controller will both be charging the batteries. When they sense the batteries at capacity they will stop charging. They probably won't detect 100% charge at the same time so you may see charge output from one device but not the other. This is how I wired my trailer and it has worked great for 3 years.

[Hetken1]

Thanks.
"It's getting better (clearer) all the time". Beatles
I hope to soon truly get the picture.

[Hetken1]

First the problem: The pull out couch sleeping size was not for two !

So we decided to have seperate sleeping on each side. One will be the dining area bed and the other this new unit.
The new unit is the same size couch and it will be a 74x30 bed.
Below on the left will be the AGM battery bank for the solar (6 batteries and misc parts). The right side now has 30x48x22 area for bedding and blanket storage during the day and couch cushion and misc during the night time.
Finish photos will follow when we make the cushioning.
Now that this is almost done I can start ripping out the "bathroom". The compostable toilet will be where the shower on the left was - the floor area in the middle where the toilet was will become a 24x24 shower - and the vanity (done over) will remain in the same location. The finish of the room will turn the space into a "wet bath". Demo photos soon
Ken