Splicing solar panels together.

[cptron]

I have 2-5watt solar panels with just the clips for the battery. I was wondering how I can hook these up together in order to get 10 watts to the battery. Can I just cut the ends off of one and splice them together?

[Divecoz]

Pos. to Pos .. Neg to Neg.. "could" end up with 10 watts.. I only say "could" , because it depends on the quality of the unit and amount of sun it's receiving..

On Edit: I see where what I said , might be confusing.. Take both the positive leads from the chargers and put them together and attach to the Positive post of the battery.. same goes for the negative.. In a perfect world you now have a 10 watt solar charger.. However without a few maybe a lot of other facts you " could " do more harm than good .. " could " be a wash..nothing gained.. " could " actually gain 10 watts.... Lots of issues with first generation solar chargers.. Not the least, a lack of diodes

[kurz]

yes, low power panels can go to the battery without regulator.

But: Please test if the panel do not change the direction and takes out power in the night.

[mastreb]

You simply connect both panels to the battery "in parallel", i.e. connect both to the battery as if the other didn't exist. If you chain the panels together (i.e., bat+ to A+, A- to B+, B- to Bat-) you will double the voltage which you don't want to do.

[Wind Chime]

Is it ok to plug my small (5.5w) solar panel driectly into my cigarette lighter plug for topping the battery?

Is it ok that I have added an extention cable to the wire to make it long enough so the panel is out from under the tarp. Total wire length is about 15 feet.

[mastreb]

Is it ok to plug my small (5.5w) solar panel driectly into my cigarette lighter plug for topping the battery?

Is it ok that I have added an extention cable to the wire to make it long enough so the panel is out from under the tarp. Total wire length is about 15 feet.

Yes, it's okay to plug in through a CLA. The wire length should be fine but be aware that the longer the wire is and the higher the gauge (smaller the wire) the more voltage drop you will have, which means less charging efficiency. The wire should be 14 gauge or lower for this run.

[Wind Chime]

Thanks Mastreb!

[Sumner]

Is it ok to plug my small (5.5w) solar panel driectly into my cigarette lighter plug for topping the battery?.

If you are keeping an already topped off battery topped off with a 5-10 watt panel that is one thing. If You go out for the weekend or even the day and come back with it somewhat discharged it is going to take a long time to top the battery back off. A 5 watt panel might give you .4 amps for 4-5 hours a day max which would be about 1.8 amp/hrs back into the battery. That isn't much. So in a week you might if real lucky put in maybe 8-12 amp/hours back into the battery.

For about $80 you could add 40 watts....

Panel...

http://www.solarblvd.com/Solar-Panels-& ... _info.html

Charge Controller...
http://www.solarblvd.com/Charge-Control ... _info.html

and be getting somewhere.

Or for $105 add 60 watts....

Panel...

http://www.solarblvd.com/Solar-Panels-& ... _info.html

Controller...

http://www.solarblvd.com/Charge-Control ... _info.html

You could rig these so that you just left the panels laying in the cockpit during the week and removed while sailing or better yet mount them...

http://purplesagetradingpost.com/sumner ... de-22.html

http://purplesagetradingpost.com/sumner ... de-33.html

...and get some real power while out sailing for a day, a weekend or longer,

Sum

Our MacGregor 26-S

Our Endeavour 37

Our Trips to Utah, Idaho, Canada, Florida

Mac-Venture Links

[Wind Chime]

Sumner, you truly are the king of solar power, and your wife is of course the queen of sunbrella!

That is an amazing rig you built. I don't think I have the need for that, and don’t have the tools or skill to make it anyway. Besides, I think my wife would lose it if I built that rig on the back of our X, unless it was strong enough for her to sit up there and read a book in the sun

I have at least a 20 minute to one hour run back to the marina under power, and have always thought that was enough to recharge that batteries, so I just have the small solar panel to keep it topped up during the week.

[Retcoastie]

cptron,
I have two 15W panels that I have in parallel. I plug them into the running light plug in front of the mast. That way it does not require additional wiring, the system is fused, and I can connect and disconnect them easily from the cabin. At night or bad weather I turn them off using the mast light switch on the fuse panel. When they start working in the mornings, the red light on the switch begins to glow. I turn them on. I do not have a regulator as the boat is stored in my barn unless I'm using it. Then the 30Ws is not enough to keep up with my usage, but I'm usually out less than thirty days at a time and usually have my meager 6 amp alternator Honda engine running or shore power along the way.

Good Luck

Ken

[cptron]

I appreciate everyones advice. I am just a weekend and vacation sailor at the time until I can retire so I an thinking since I have 2 batteries, house and starter, that run through a disconnect/seperator switch (don't recall the tech term) then I should be able to connect a solar charger to each battery and they should work in tandem to keep both charged. Is this a fair and correct statement?
Ron

[Catigale]

I have at least a 20 minute to one hour run back to the marina under power, and have always thought that was enough to recharge that batteries, so I just have the small solar panel to keep it topped up during the week.

Windchime - have you ever calculated your typical electrical loads? One hour of run time with a 200 Watt Alternator will replenish at most 20% of one group 24 battery capacity and more likely about 10% of same.

[Rick Westlake]

I put a 15-watt Sunsei solar panel on top of my hatch slider as a winter project, the first year I had Bossa Nova. (The mod is http://www.macgregorsailors.com/modt/in ... ?view=1128.)Being a glass-topped panel, though, it didn't last ...

So in February 2011 I removed the Sunsei panel and its supports, and installed two 12-watt Sunwize Solcharger panels on my cabin top forward of the hatch slider. These panels are made with a fiberglass base and topped with clear resin instead of glass; they're billed as "vandal resistant.") I connected them in "series" (pos-to-pos, neg-to-neg) to a length of 12-gauge, 2-conductor cable; I pulled the cable through the space between the deck and the head liner, and back to the battery compartment (under the seat at the end of the galley, across from the head). And I connected them to a dual-battery charge controller which feeds each battery separately.

This new mod is at http://www.macgregorsailors.com/modt/in ... ?view=1657.

I am a big believer in overkill ...

[RobertB]

connected them in "series" (pos-to-pos, neg-to-neg)

Sounds like an interesting installation. A minor nitpick (if i do not do it someone else will) - what you describe is a parallel installation - the correct way to preserve the 12 VDC output.

[cptron]

Thanks retcoastie, That sounds interesting and I may try that. At least I can then get the wire out of the companionway and make the admiral happy. If Admiral is happy then everyone is happy. Right