29BHDS solar

[JMC]

We just ordered our trailer, but i have been researching solar for a couple months. We plan to dry camp a lot and don't want to hear a generator where we'll be camping... at least not our own generator.

I've been looking for deals on the parts I want to use. And already have the big items purchased/delivered. The system will use:

* 705W solar via (3) 235W panels
* (4) CR260 6V batteries - 260 AH
* Magnum MS1012 pure sine inverter + 50A charger
* Morningstar TS-MPPT-60 solar controller
* AC sub-panel for trailer outlets
* Proper breakers, fuses and on/off switches and wiring

I will likely hold off on buying a generator in hopes that we don't need one. If we need one for any reason, I'd like to limit it to a 2000W Honda that's converted to LP.

[JMC]

Can someone confirm where the Jayco "solar ready" wiring terminates inside the trailer? Based on earlier posts on the forum, it sounds like its #8, which will be good enough for me...

[Seann45]

Hmmm 705 watts I would be wanting bigger than 8ga wire.. I run 4ga from each panel to the roof junction box then 1ga down to the charge controller.. 00 between each battery and to the inverter..

[JMC]

Yeah, hoping to use as little of the #8 as possible to get me through the roof. And then I'll take larger wire to the controller.

And the panels are 24V and rated at 30. I plan to try them in series which would equate to 90V @ only 7.8A.

[Cdash]

I just starting on this learning about solar, but isn't that a heck of a lot of solar wattage for just 4 batteries?

Is there enough shade fee real estate on the roof for that much panel?

I'm thinking ahead to solar, but was thinking of 2 batteries to start. I'll be curious to see how yours comes together.

[JMC]

I got a great deal on the panels. Craigslist find for $0.81 per watt; brand new panels. Hard to pass up...

So I probably have a little more than I "need" but the worst case is that I'm fully charged by 11AM and end up throwing away some power. The broad rule of thumb is a watt of solar per AH of battery. I'm at 705W on 520AH.

I pulled up the calculator on the wire gauge and loss. If i run the panels in parallel over 10 feet of #8, its a ~0.5% loss. Ran in series is ~0.06% loss. I'm comfortable with these. I'll run some larger wire starting at the first spot I can inside the trailer.

[Mustang65]

Do you have the manufacture/model of the panels?

Just to insure you are getting what you ordered on Craig’s list (or even eBay) take each individual panel and verify its output against what the mfr specifications have for that panel. Not that it will happen to you but a lot of the panels sold on those sites are new, but are either blemished (can affect ouput) or panels that did not meet the manufactures specifications.

Just check them out before you mount them on the roof.

Don

You may find some additional information on the "RVing with SOLAR" Social group under Comunity.

[JMC]

That's a good idea... i'll check them.

they are LDK brand. Model is LDK-235P-20.

[PlayersZ28]

AFAIK if you put them in series and part shade one panel you lose all of them. Parallel avoids this at the expense of bigger wire.

[JMC]

Yep, i've seen some of the shade threads online. There seems to be enough agreement that shade is "complicated" that I'm going to try series first. My panels have six bypass diodes, which evidently helps with the shade factor. Worst case is that I have to move them to parallel... thanks!

[Northern Jay]

A suggestion for testing before installation. Connect everything on the ground in series and hook to batteries and see what kind of output you get. Then shade the panels partially and see what happens to output. Do same in parallel and then decide which way to install them.
Happy Camping

[JMC]

That's another good idea... Thanks

[Mustang65]

Originally Posted by Northern Jay

A suggestion for testing before installation. Connect everything on the ground in series and hook to batteries and see what kind of output you get. Then shade the panels partially and see what happens to output. Do same in parallel and then decide which way to install them.
Happy Camping

The output of the shaded panel is what you will get for the entire system, if the panels are wired in series.
Don

[JMC]

Now I'm second guessing myself. I liked the nearly non-existent loss on the wire with the high voltage, but likely isn't worth the hit from running them in series. If the amount of the #8 i have to use is under 10' I'll likely just run them in parallel and deal with the 0.5% loss.

Can anyone confirm where the factory cables terminate inside the trailer?

[JMC]

Some boxes are starting to arrive this week... Got a good deal from iMarine on this. It showed out of stock so I called them. They actually just have this model drop shipped and it came within a few days.

MMS1012 that will be hardwired with a sub panel for the trailer AC outlets.

[Mustang65]

If you can purchase another panel, you can run them in Series/Parallel. This way you are only losing up to half of your total, providing 2 panels are in the sun when the other 1 or 2 are shaded.
Don

[Cdash]

Originally Posted by JMC

Now I'm second guessing myself. I liked the nearly non-existent loss on the wire with the high voltage, but likely isn't worth the hit from running them in series. If the amount of the #8 i have to use is under 10' I'll likely just run them in parallel and deal with the 0.5% loss.

Can anyone confirm where the factory cables terminate inside the trailer?

From what I've been reading, you want to keep loss less than 2%. I don't think I'd be fretting over the difference between 0.5% and your other number.

From what I understand the wires will terminate behind the white panel in the basement storage. Not sure if it is on the battery side or other side. Don't have one yet, so cannot confirm for you.

The other guys suggestion about 4 panels paralleled in two groups is an interesting thought.

[JMC]

My solar controller showed up yesterday. Morningstar Tristar TS-MPPT-60. Sure hoping to get a VIN on the trailer this week...

[Mustang65]

Here is my Morningstar MPPT 60 installed.

Now the FUN part begins.. have fun

Don

[JMC]

VERY nice install. Hoping mine looks similar...