Solar charger and battery


JVMJR

New member
We have a 1993 Eurovan which came with a solar panel on top. Don't know the output of the panel (no info came with it), but the controller is a SunSaver -6 (S-6-12v).

One question (which arises from the fact that our manual is in French) which might be related to the existence of the panel. Why does my battery indicator on the overhead panel (where fridge controls are located) flash? When I start the car the battery symbol disappears then when turned off I get a constant battery symbol and the first and last bars of the ramp like indicator. No indication of actual battery voltage. After a minute or two the flashing battery symbol resumes. All of this when the controller is showing the batteries as charging.

Any thoughts?

Thanks,

John
 

johnt55

Member
Can't help you with overhead instrument panel, but I can help with the solar questions.

The U.S. made Sunsaver is a solar controller rated at a max of 6 amps. A popular unit used in many PV, (photovoltaic) systems. Plenty for what you're doing. What it does is regulate the energy produced by the PV solar panel on top. Here's some info about it: http://www.morningstarcorp.com/en/support/library/SS.IOM.01.EN.pdf.

If the energy coming from the roof-top panel is too low, the controller cuts the connection - too high, and it shuts it off. Think of it as a very sophisticated battery charger which prevents the battery from being over-charged, or allowing its voltage to drop below 11.5 volts. Either extreme can damage a battery.

This Sunsaver unit is only for a 12 volt system. (6 amps max) To know what the solar panel is putting out, locate the Sunsaver module and put the leads of a multimeter onto the wires coming from the solar panel, (terminals 3 & 4, marked solar on the Sunsaver unit). In full sun, the panel should put out anything from 16 to 18 volts. (You need the higher voltage to charge up a 12 volt battery. A fully-charged 12 volt battery actually puts out a bit over 14 volts.) The unit, like most other PV regulators, also prevents the solar panel from discharging the battery at night!

If your battery ever gets totally discharged, you can connect it to any typical battery charger without having to disconnect the Sunsaver. Solar panels are strange creatures. If you park under a tree and the panel is partially obscured, the energy produced by the obscured cells drops as a result. Unfortunately, all the cells in the panel will then drop to the output level of the obscured cells. So, keep this in mind.

Hope this helps.
 
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Den1900

New member
I have a 1981 Westy, I am looking to install an aux battery system to run the stereo, 1 light, and refrigerator and maybe power inverter. I was thinking of having the vehicles charging system recharging the battery when the engine is running, and adding a solar panel to charge while stopped. The refrigerator would run off the vehicles charging system when the in vehicle is running and both batteries will be isolated. Would this system work? Any advice on this type of system or another way to do it. I was thinking a 80-100ah aux battery and a 50-80w solar panel. Here are the specs to the aux. devices.

refrigerator 12vdc 2-6.5a 40ah averge a day
1 light 12vdc 15 watt 4 hours a day
stereo 4 hours a day
maybe a power inverter 500w, would just charge laptop or camera, not everyday
 
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johnt55

Member
Solar Westy!

A decent mono, or poly-crystalline panel that yields 50-80 watts @ 14-16 volts will probably cost $300 to $500 and will be around 2 x 4 feet in size. Prices have been dropping and well-made panels are half of what they cost just a few years ago. Amorphous panels are much cheaper, but would require double the L x W dimensions and still yield fewer amps. I also have an 81' Westy. I searched all over the Net and could never find a panel that was the size I needed - always too long, short, etc. Since making solar panels from scratch is a semi-hobby of mine, I made one which permanently fits in the roof luggage area above the front seats, (which I never use anyhow). I just returned from a 9,500 mile, "search for my inner a-hole" trip around the U.S. and Canada and the panel kept my large, deep cycle battery charged up nicely. I used it to run a small coffee maker, toaster, stereo, laptop, fan and extra LED lighting here and there.

There are many ways to go. I know that some people store a large panel between the cushions upstairs and just set it up outside when they stop in one place for a few days. Unfortunately, no matter how large your panels are you'd be hard-pressed to generate enough juice to operate the refer continuously. Eventually, the battery output will drop below 12 volts and the DC/AC inverter will get very upset and start beeping like crazy. The advertised power output ratings for factory built panels are optimal and never equal real world conditions, (i.e., a cloudy day, parked under a tree, weather, northern latitude, etc.). Running all the other stuff should not be a problem, just the refer. I ran my built-in Westy refer almost continuously, day and night, on-road and off for 5-6 weeks on just two tanks of propane. Hard to beat that. Of course, I'd plug in to AC and turn off the gas when I could.

The heavy, deep cycle battery I use is located on the passenger side under the rear, fold-out seats. There's too much weight on the driver's side of a Westy already! Because DC voltage from any solar panel drops quickly even over a short distance, I ran heavy, eight gauge copper wire from the panel to the solar regulator, also under the seat. Then to the battery, to the inverter and to a new AC outlet I installed near the standard Westy AC outlet. I also installed and connected two 12 volt, cigarette lighter-style outlets directly to the battery to run other small stuff.

Many use the Harbor Freight three panel, 45 watt system which can be had for $150.00, complete with regulator and two 5 watt DC fluorescent bulbs. CHEAP! They are the amorphous type and have a 3-4% conversion efficiency as compared to the silicon types which average 12-14% in conversion efficiency. The Harbor Freight panels are quite large considering the small amount of energy they provide, but they're light weight and just an inch thick. In full sun they might keep a small motorcycle battery charged up, but where would you install those three large panels so it wouldn't look too ugly?

A bit of solar energy trivia: A single silicon solar cell, no matter how large or small it is, always delivers about one half watt. So, to deliver 12 volts you'd have to connect 24 individual cells together. You actually need 14-16 volts to charge a 12 volt battery.

Hope this helps!
 

xp64beta

New member
Ok I bought a solar charger a small one for 20 bucks from harborfreight.com/ yeah its Chinese and yeah it might fail / most reviews say the mid wire junction connector plug is weak or weakens. Mine seems fine. Unfortunately the cigarette lighter is stuck in the cigarette lighter socket. somewhere in Accessories forum there is supposed to be a topic on replacing the cigarette lighter with an American 12 volt Accessory outlet. I can not find this topic anywhere. There was supposed to be one that hooked right up to the stock wiring was my impression. Can anyone direct me too this? Thought about velcro adhesive strips for the charger on the dash. This is just a possible solution for a trickle charge without a cord.
 

johnt55

Member
You're probably talking about the 5 watt panel from Harbor Freight. It works fine. Actually, I think they're well-made. My daughter drove into one and it still works!
 

rcook52459

New member
you can get at the socket and unplug it with the glove box open all the way.if i remmber right it you can get a socket to fit almost anywhere.the wiring will plug right in.look on the back of the socket your going to buyand see if the terminals will fit(like L shape.i no that's not how to describe it)it's pretty standard though.the wire that goes to the middle of the socket is the hot wire and the wire that on the side is ground wire.i wish i could say it better.when you get the new socket you'll see how to put in.it's not hard
 

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