Solar to Panel?

[joel1]

Good afternoon,

I'm in the process to setting up a solar panel setup and my fuse/breaker box is inside under the stove and my batteries are currently in the front outside.

I was wondering if it's possible to run my solar panels (from the roof) by the fridge vent to a charge controller and from there go to the 12v electrical panel instead of going to the batteries. The batteries are connected to the panel but not sure if this would charge them.

I looked online for any setup like this but couldn't find anything which is why I joined this forum for some answers.

[MrWizard]

the fuse goes between the panels and the solar controller

be advised with most controllers
you are supposed to connect the batteries first, then the solar panels

if changin batteries or doing any thing like that

disconnect the PANELS FIRST, Then the batteries last

panels connected to a controller with no batteries can burn out the controller

[CA_Traveler]

Boon Docker wrote:

CA Traveler wrote:
Charging will be compromised from very small to unacceptable. Wire size, length and amperage (ie solar size) are the main considerations.

The factory wire size would have to be very small to be unacceptable. I don't think that they install wire quite that small between the converter and battery.

My 200 watt system with a 15 foot run from converter (where charge controller output is connected) has a .50 % loss at full output.
A 400 watt system would have a 1.0 % loss.
A 600 watt system would have a 1.5 % loss.
All very acceptable.

Good point but very few posters know their % loss. While connecting to remote wires can be a good solution the compromise is that the CC MAY not know the actual battery voltage because the CC does not have remote voltage sense.

I don't know the OPs situation but the closer to the battery and the less loss the better. After all the typical CC unlike the rigs charger has limited charging time and less amp capability.

[CA_Traveler]

joel1 wrote:
I could do that just wanted to avoid drilling any holes on the roof.

That's a common scenario and doesn't stand the test of good sealing.

After removing the Hughes dish and replacing the Monaco sat dish I had a number of holes. Then more holes for the solar panels and the roof is like swiss cheese but completely sealed.

How many holes do you currently have for fans, vents, awnings, A/Cs, TV antennas to name a few?

[corvettekent]

I drilled a hole in my roof, put a 3/4" PVC conduit in and sealed it with Dicor. No leaks in four years.

[joel1]

I could do that just wanted to avoid drilling any holes on the roof.

[corvettekent]

Why not mount your solar panels on the roof at the front of the trailer? Then you wire run will be much shorter.

[Tango__AE7UI]

My fifth wheel is set up the same way; breaker panel below the reefer on the rear wall and batteries all the way forward.
(2) 140 watt panels on the roof.
I came down the reefer vent to the breaker panel and it works very well.
It may not be the best solution but, not much else you can do.

[joel1]

Well that's why I was thinking that I could since the converter is ar the same location and it charges the batteries from the same distance.

[Boon_Docker]

CA Traveler wrote:
Charging will be compromised from very small to unacceptable. Wire size, length and amperage (ie solar size) are the main considerations.

The factory wire size would have to be very small to be unacceptable. I don't think that they install wire quite that small between the converter and battery.

My 200 watt system with a 15 foot run from converter (where charge controller output is connected) has a .50 % loss at full output.
A 400 watt system would have a 1.0 % loss.
A 600 watt system would have a 1.5 % loss.
All very acceptable.

[mike-s]

joel1 wrote:
Thanks for the input guys. At which area would you add the DC breaker or fuse?

Before the panel?

You should have a DC breaker (fuse is 2nd choice) between the solar panel and the controller. Many/most controllers will smoke if the panel is connected when the battery isn't. A breaker can serve as a switch (a fuse is more hassle) so you can disconnect the solar before working on the controller or battery. And you can get a DC breaker for about the same cost as a switch, if you're willing to wait a couple/three weeks to get it.

You should also have a fuse or breaker on the run between the controller and the electrical panel, close to the panel. That's to protect against that wire getting shorted somewhere, and in most rigs the only other protection would be a large self-resetting breaker near the battery. As mentioned above, you could probably backfeed the panel through a spare fused DC circuit, although something makes me feel that's not the right thing to do.

[time2roll]

Fuse? What is the combined Isc panel rating? If you can connect to an open fused port in your stack of fuses in the distribution panel you are fine. I believe most are 15 or 20 amps max. The rest of the wire should have enough ampacity to short the power from the panels with no harm done. More concern with converter amps and battery amps melting the wire.

[CA_Traveler]

Charging will be compromised from very small to unacceptable. Wire size, length and amperage (ie solar size) are the main considerations.

Do you have other wire routing options? On my sons 5er we ran the wire down a front closet to the controller next to the battery located in the front for example. No visible wires inside.

[joel1]

Thanks for the input guys. At which area would you add the DC breaker or fuse?

Before the panel?

[mike-s]

Yes. It will work best if your controller has remote voltage (and temperature) sensing. But it will work. Make sure there's a fuse or DC breaker in line.

Connecting to the battery connections at the panel would actually be better than running wires (of the same gauge as the existing battery-panel wires) separately to the battery. That's because whatever current you use beyond charging during solar hours wouldn't have to travel to the battery and back to the panel.