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Topic: Off to the Mothership to Order Mid-bath (Read 37 times) previous topic - next topic
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Re: Off to the Mothership to Order Mid-bath
Reply #50
Yahoo Message Number: 129548
"Add on to existing seemed much more practical to me"
 But as noted, the way the factory mounts solar panels nearly flush with the roof and un-tiltable makes their electrical connections inaccessible. To add more, you have to have at least one of the existing panels removed, rewired, and then remounted. Believe me--I've been through this. Possible? Yes. "More practical"? No.

Andy Baird http://www.andybaird.com/travels/
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"


Re: Off to the Mothership to Order Mid-bath
Reply #52
Yahoo Message Number: 129552
Quote
"Add on to existing seemed much more practical to me"
I have been throught this too.  AM Solar pointed out to me that the factory wiring for my single panel was not adequate for adding on any more.  They replaced everything.

Re: Solar panel shadowing
Reply #53
Yahoo Message Number: 129553
Quote
And here is a link that does a pretty good job of explaining when tilting makes sense
 http://wheelingit.wordpress.com/2011/11/15/rv-solar-part-iv-panel-tilting-winter-solar-optimization/

Mostly for long term boondocking in winter in the desert if I read that right. Horizontal panels probably fine in summer.
At Quartzsite last January, we experimented with several rigs with tiltable panels.  Comparing flat and tilted it was verified that tilting panels in most cases and configuration, was just shy of doubling the output.

Re: Off to the Mothership to Order Mid-bath
Reply #54
Yahoo Message Number: 129554
Andy, For those of us with the factory mounted panels, would it be worth it to have a separate panel on the ground that one can tilt easily by hand, if we wanted a little extra juice for minimal cost (still using the two house batteries)?  I'm thinking of winter application.
By the way, I did stop at AM Solar last year to review our solar set-up on our 1998 LD MB with the two panels from the factory (85 watts each).  Basically they said they would have to start all over to place new ones in. And... that it would not be practical to add another 85 to the mix because of extra costs for rewiring, etc.  So we are happy with what we have since it covers all of our needs for Computers, Lights, TV, etc.  Maybe...we could use a bit more in winter.  So far, it has not been a problem.
Thanks in advance.
David

Re: Off to the Mothership to Order Mid-bath
Reply #55
Yahoo Message Number: 129555
Quote

"I have been throught this too.  AM Solar pointed out to me that the factory wiring for my single panel was not adequate for adding on any more.  They replaced everything."
Roger

Hmmm, very interesting!
 The 1st time AM Solar did work for me was to remove the two 85W panels installed by the factory. They then installed two 100W panels in different locations.
 The second time they did work for me was to install two Lifeline AGM batteries.
 The next time they do work for me [probably this summer] will be to add a 3rd panel and upgrade the wiring.

Steve S.
Lazy Bones & Jiggs
Steve S.
Lazy Bones & Cedar
2004 30'IB (Island Bed)
Yesterday is History, Tomorrow is a Mystery
Live for the day!

Re: Solar panel shadowing
Reply #56
Yahoo Message Number: 129556
Quote
At Quartzsite last January, we experimented with several rigs with tiltable panels.  Comparing flat and tilted it was verified that tilting panels in most cases and configuration, was just shy of doubling the output.
This is a complicated subject; too many variables.  I have a spreadsheet that calculates the theoretical number of amp hours you will get at different locations, etc.
 At Quartsite (N33.7 deg) at mid winter (Dec 21) if you tilt the panels by 45 deg the sheet predicts that you will get just double the number of amp hours out of the panels.  That is, if the panels face due south.  It falls to by 17% from that value if the panels face 30 deg from due south. That's pretty much in keeping with what you measured. Note that like all calculations, this spread sheet approximates reality but it is useful in understanding how solar power works.
 By the first day of spring, the gain by tilting is much smaller; only 18% to 20%.  On the first day of summer (at Quartsite again) there is a net loss by tilting the panels (~ -16%). Even if you travel well north (48 deg) and tilt the panels just the correct amount (24 deg) it is a wash whether or not the tilt helps any.
 The spread sheet is in Excel and I will share it with anyone who wants it.  Contact me: gumm at easystreet dot net and I will e-mail you a copy.

Linley

Re: Solar panel shadowing
Reply #57
Yahoo Message Number: 129558
"At Quartzsite last January, we experimented with several rigs with tiltable panels.  Comparing flat and tilted it was verified that tilting panels in most cases and configuration, was just shy of doubling the output."
 I've said this before, but I'll repeat briefly here: I don't tilt my panels often. There've been times when a year went by and I didn't have the need. But when the need arises--as it did when I dry-camped at Catalina State Park this winter--being able to tilt the panels makes a big difference. It can be the difference between enjoying peace and quiet, or running the generator several hours a day. It can be the difference between enjoying lovely scenery in a remote location, or deciding that it just isn't worth the trouble, and moving to a commercial park with hookups and a closeup view of your neighbor's slideouts.
 So to those who say you probably won't bother to tilt your panels most of the time, I agree. But when you need to, it's great to have the option.

Andy Baird http://www.andybaird.com/travels/
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"

Re: Off to the Mothership to Order Mid-bath
Reply #58
Yahoo Message Number: 129559
"For those of us with the factory mounted panels, would it be worth it to have a separate panel on the ground that one can tilt easily by hand, if we wanted a little extra juice for minimal cost (still using the two house batteries)? I'm thinking of winter application."
 I've seen trailer owners do that, but it has several drawbacks. First, where are you going to carry the panel when not in use? A modern 100W-150W panel is bulky, and a smaller one probably isn't worth the trouble.
 Second, you'll need to place it so that it isn't shaded by the rig itself. (With roof mounting, of course, this isn't a problem.) That probably means siting it well away from the rig, which in turn means a long cable connecting it to your existing system. A long cable wastes power, unless it's a very heavy one. And then you have to store the cable as well.
 Also, a freestanding panel could easily be stolen. All it would take would be for somebody to drive by with a pickup after dark, clip the wires and lift the panel into the back. Trucks drive past campsites all the time, so you'd never notice until the next morning.
 Mounting a panel on the roof obviates all these problems. I think if you're going to add a panel, that's probably the best way to go.

Andy Baird http://www.andybaird.com/travels/
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"

Re: Off to the Mothership to Order Mid-bath
Reply #59
Yahoo Message Number: 129580
Were they able to use the same wiring runs, just pulling heavier wire along the factory cable routing?

Dan


Re: Off to the Mothership to Order Mid-bath
Reply #61
Yahoo Message Number: 129584
Quote

Nope.  All new.
 
 Were they able to use the same wiring runs, just pulling heavier wire along the factory cable routing?

Dan
Roger
 The still unanswered question is; Did they route the replacement wires through the same path as the originals were run?

Steve S.
Lazy Bones & Jiggs
Steve S.
Lazy Bones & Cedar
2004 30'IB (Island Bed)
Yesterday is History, Tomorrow is a Mystery
Live for the day!

Re: Off to the Mothership to Order Mid-bath
Reply #62
Yahoo Message Number: 129587
"Were they able to use the same wiring runs, just pulling heavier wire along the factory cable routing?"
 Since the factory securely ties down all cables every couple of feet, it's not likely you'd be able to pull a new cable along the same path. You might be able to push or pull a new cable along the same general route, but that's not a sure thing.
 For example, if at some point the factory's cable takes a 90° turn and passes through a hole in a stud or cabinet wall, that may be difficult to duplicate when working blind with new cable, since you won't have the advantage the factory did: they install all wiring before the walls go on.
 This isn't to say that you can't install new cabling... just that you're probably going to have to find your own path for it. You won't be able to just pull it through existing cable trays or conduits, because there aren't any.

Andy Baird http://www.andybaird.com/travels/
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"