Community Forums

KJR · 04-14-2019, 07:30 AM

We are going to look at a 2019 Ventana Le 3717 that doesn’t have the 6g solar prep. We would like to add solar later. How is solar wire led down from the roof with so many slides. I believe the six 6v batteries are located behind the drivers front wheel under the living room slide. Is it a difficult DYI or should if be left to a qualified installer? I would imagine the labor to just run the wire to the battery compartment would be a lot more than the cost of the factory option.

KJR

RVific · 04-14-2019, 07:52 AM

I'm getting solar installed on my new ventana in June. The installers will be using 2 gauge from the roof to the batteries, they think that the 6 gauge factory wire is not big enough, and told me I should just save the few hundreds that the prep cost. I am surprised I don't see much on these forums advocating such a big wire.This is a mobile installer recommended and apparently trained in some way by AM solar.

Luv2go · 04-14-2019, 01:07 PM

I agree with the larger wire that AM Solar-trained installers suggest, you want to minimize the voltage drop. With AC wiring, normally 3% is acceptable, but with solar I like to see 1 or 2% at the most.

It's obviously less costly to put the larger wire in after the fact than to pay for the option and then have to replace it, so I would not be concerned about not having the prewire.

KJR · 04-14-2019, 02:34 PM

Where does the wire route down from the roof?

Thanks

KJR

Luv2go · 04-14-2019, 07:24 PM

Normally they route it down from the roof to the cabinet the controls are in and then down and back to the battery bay.

Renipladlo · 04-14-2019, 10:45 PM

When had the farm, I had to install a new meter base on the pole and run wires to the barn about 100 feet away. The electrician used #6 wire to feed the 100 amp service I installed there. If it can carry 100 amps it sure as heck can carry as much as 500 watts of solar. Now, #6 and 6ga wire are different, but Ranger bass boats used 6GA for the onboard battery charger, which was sure as heck heavey enough for that. The amp load from those panels wont be that much I don't think so I think you are good with factory wire.

Luv2go · 04-14-2019, 11:43 PM

Quote:

Originally Posted by Old-RVer

When had the farm, I had to install a new meter base on the pole and run wires to the barn about 100 feet away. The electrician used #6 wire to feed the 100 amp service I installed there. If it can carry 100 amps it sure as heck can carry as much as 500 watts of solar. Now, #6 and 6ga wire are different, but Ranger bass boats used 6GA for the onboard battery charger, which was sure as heck heavey enough for that. The amp load from those panels wont be that much I don't think so I think you are good with factory wire.

Interesting that your electrician used #6 AWG copper for 100A. Nowadays the NEC only allows 75A max for #6 per this chart. You would need at least #4 for 100A service entrance now (per note 5 under dwelling units, which may or may not be allowed). This is from the 2002 code.

Renipladlo · 04-16-2019, 07:47 AM

It might have been #4, been a few years and cannot remember for sure, can still see the extra pieces I rolled up and put on the wall, but the money pit sold this past Winter, and brother glad to see it go. I worked up there for months and never saw any results for it all, then the druggies took over the place adjacent to the corner, sheriff was powerless to do anything without cause. I told him he did not want me to take care of it, he agreed, WA, CA, OR, CO and several other states are going to pay dearly (taxes they charge you) for those liberal drug laws, and keeping the homeless warm, fed, and drugged up. SOOOOOOOOO glad we are not living there any longer.

Finance · 04-16-2019, 08:07 AM

Large wiring is not necessary with MPPT controllers and large panels in series, which is the best performing design with current technology.

Chasing a vent pipe down through interior walls works in some cases. You can also pretty easily get to the front cap by fishing through the attic, then follow inside the A pillar to get under the dash and below the floor.

C.Martin · 04-16-2019, 07:41 PM

Quote:

Originally Posted by KJR

We are going to look at a 2019 Ventana Le 3717 that doesn’t have the 6g solar prep. We would like to add solar later. How is solar wire led down from the roof with so many slides. I believe the six 6v batteries are located behind the drivers front wheel under the living room slide. Is it a difficult DYI or should if be left to a qualified installer? I would imagine the labor to just run the wire to the battery compartment would be a lot more than the cost of the factory option.

KJR

Running wire from the roof is NOT going to be fun. On our floor plan...the wire probably is run down thru the 1/2 bath walls (non slideout) to the basement. The roof wires are located under a metal plate on the roof. The other end was terminated on the bulkhead nearest the battery compartment in the pass thru bay. A network cable is also included...that starts in the control panel location..and terminates along with the 6 AWG wire near the battery compartment. The idea is to keep the run as short as practical.

If you have 6 Interstate Lead Acid batteries...they are usually around 220aH each. Wired together as 12v...that would be a 660aH bank. Interstate recommends C/10 charge rate...in your case 66 amps. I use 14.51 volts as my absorb voltage. At that rate...you are putting 66A x 14.51V = 957.66 watts.

If you wire two 180watt panels in series...they output around 42v when pushing out a bulk charge. 957.66 watts / 42v = 22.8A. So...the assumption that the wire running from the roof to the controller needs to be rated for 100A is not correct.

For your bank...I would go with six 180w solar panels configured in three Strings of two... but check the input requirements for your particular MPPT controller.

I have eight x 232aH 6v Interstate batteries..running eight 180w panels 2s4p...and use the 6 AWG solar prep... Victron SmartSolar MPPT150/100 controller.

I performed all the calculations ...included the recommended factors to the voltage and amperage for my system...and 6awg from panel combiner to controller is what was needed.

http://www.cooperindustries.com/cont...-app-guide.pdf

I would recommend either doing the computations yourself...or patterning your system off someone that knows how and has performed the calculations.

I have a lengthy thread on my learning experience. I am extremely happy with my final result. Here’s the link...

http://www.irv2.com/forums/f103/2016...on-337300.html

If you are capable of handling the panels and basic wiring and power tool use...I think you’ll perform a quality installation. I can’t comment in the professional installers. I would get reviews from other coach owners with their systems installed.

Don’t get the factory option...you can do much better, in my opinion.