Solar Set Up Help

[ButchDeal]

It's a device that connects your start battery and house batteries so that excess energy produced from the alternator will charge your house batteries but will also allow flow from house batteries to start battery when it sits. So you'll never have issues of draining the start battery

That is actually called a battery isolator not a battery combiner.

[tigerremod]

What is a Battery Combiner ?
A Solar PV Combiner is a fused junction box where several parallel PV panels are combined. It does not make any greater amount of electricity, it's merely a safe way to connect things together.

It's a device that connects your start battery and house batteries so that excess energy produced from the alternator will charge your house batteries but will also allow flow from house batteries to start battery when it sits. So you'll never have issues of draining the start battery

[Mike90250]

..........
I am also thinking of getting a battery combiner as a supplemental way for charging the battery bank. So could that make up for having only 300 watts of panels?

What is a Battery Combiner ?
A Solar PV Combiner is a fused junction box where several parallel PV panels are combined. It does not make any greater amount of electricity, it's merely a safe way to connect things together.

[tigerremod]

Your CC is limited if you decide to enlarge your system but your real issue is you now have a 12v battery system so a 24v inverter will not work.

You also now have a 400Ah battery system which will need about 40 amps of charging which comes to about 500 watts of panels.

Thank you for all the feedback! I could get a different inverter.
I am also thinking of getting a battery combiner as a supplemental way for charging the battery bank. So could that make up for having only 300 watts of panels?

[SunEagle]

So wire my batteries parallel and problem fixed?
Do I need a larger charge controller?

Your CC is limited if you decide to enlarge your system but your real issue is you now have a 12v battery system so a 24v inverter will not work.

You also now have a 400Ah battery system which will need about 40 amps of charging which comes to about 500 watts of panels.

[littleharbor]

With a single panel you will be fine with the system at 12 volts. If you ever want to expand the controller needs to be replaced, UNLESS, you want to go 24 volts, then you need to add a panel. Of course your inverter is only good for it's designated system voltage.

[tigerremod]

Yes it does. If you had a 12 volt system this setup would work fine. Matter of fact you wouldn't be able to add another panel due to your relatively small 20 amp controller.

So wire my batteries parallel and problem fixed?
Do I need a larger charge controller?

[littleharbor]

I don't have room for another panel as this is going on top of my camper and the 300w is large, I know of people that have the same set up but their batteries are wired parallel, not sure if that makes a difference. I've heard that batteries should be wired in series.

Yes it does. If you had a 12 volt system this setup would work fine. Matter of fact you wouldn't be able to add another panel due to your relatively small 20 amp controller.

[tigerremod]

I don't have room for another panel as this is going on top of my camper and the 300w is large, I know of people that have the same set up but their batteries are wired parallel, not sure if that makes a difference. I've heard that batteries should be wired in series.

[tigerremod]

Please reply with ...
a) The exact model # of the PV Panels
b) The exact model # of the MPPT Charge Controller

Not sure of exact model numbers but I can tell you what they are...
a) Renogy 300W 24V Monocrystalline Panel
b) Victron SmartSolar MPPT 100|20 Solar Charge Controller

hope that helps

[SunEagle]

A 24 Volt to 12 Volt DC converter will easily solve this problem ...

Yes. The OP could use that type of converter to generate 12V. But how big should it be? That will depend on the 12V loads.

Bigger problem is what littleharbor has pointed out. A single 24V panel will not be enough to charge a 24V battery system.

[NEOH]

Please reply with ...
a) The exact model # of the PV Panels
b) The exact model # of the MPPT Charge Controller

[NEOH]

PV Panels => Fuse => Charge Controller => Fuse => 24 v Battery

24 v Battery Bank => Fuse => 24 v Inverter => Fuse => 120 V AC appliances
24 v Battery Bank => Fuse => 24-to-12 V DC down converter ( properly sized by amps ) => Fuse => 12 V DC devices

"Fuse" may be a Fuse or a Circuit Breaker
Use "DC Rated" fuses for DC circuits
Use "AC Rated" fuses for AC circuits

[littleharbor]

I think 60, they're PERC solar cells, which I read were more efficient.

Then you have a couple issues. One, a single 24 volt panel isn't high enough voltage for an MPPT controller, and two, a 60 cell panel is considered more of a 20 volt nominal panel.

Easy solution. get one more panel. and series wire them.

[tigerremod]

A 24 Volt to 12 Volt DC converter will easily solve this problem ...

Thank you NEOH!
Now my next question is where do I put the converter in all of this? After charge controller? From batteries to fuse box?