12v parallel

[[email protected]]

I'm working on a chicken coop lighting situation. I was going cheap and tried to use what I have. I have an old 12v car battery that I used Epsom salt and 2 weeks of charging to restore and a 750 watt inverter. The battery should give me about 45 amp/hours and I plan to use a 5 - 23 watt incandescent light bulb. At 23 watts that's (23/110)x10 = 2.09 amp/hours. 45 amp/hours will give me about 21 hours of light if my math is right.
Now I want to see if I can extend my hours of light by adding a 12v deep cycle battery in the mix (golf cart battery). Does anyone know what will happen if I wire a 12v 800cca car battery with a 12v deep cycle battery in parallel with a 5watt solar panel attached? Will it charge? Will it damage my batteries? Will it damage my solar panel?

Thanks,
Minh

 

[Bullzeyebill]

Not flashlight related, but I'll keep this thread here. Some of our battery experts can give you some input.

Bill

 

[[email protected]]

Is there a better place to put my questions. I'm new on this site.

 

[mvyrmnd]

The best way is to stock with watts, until you're at the battery.

The bulb uses 23 watts. The inverter will cost you some power, so let's make it an arbitrary 25 watts.

25W at 12V is 2.08A. If your battery holds 45Ah, then theoretically you should get a runtime of ~21.5 hours. This does not take into account any losses due to resistance in your wiring and internal resistance in your repaired battery.

If you are going to wire up a second battery, you really should make it of the same type and capacity.

Adding the solar panel can't hurt. Assuming it actually manages to provide 5W, then you could just redo the equation starting at 20w.

When are the batteries going to be rested and recharged? If it was to be run full time like this, you're just going to kill your battery.

 

[Wrend]

You'll want an adequate Pb charge controller and to make sure your panel is up the task.

I personally would just use the deep cycle battery. The car batteries are made for short bursts of power, not sustaining power.

You might also want to look into some 12VDC lights.

 

[[email protected]]

I was looking into putting some 12vdc lights to take the inverter out of the equation, but with the inverter I can plug in my power tools I use for maintaining and update my chicken coop. Would you know any ill effects of putting the deep cycle battery with the the car battery? I want to try it but don't know if it will cause any damages to my setup.

 

[CKOD]

I was looking into putting some 12vdc lights to take the inverter out of the equation, but with the inverter I can plug in my power tools I use for maintaining and update my chicken coop. Would you know any ill effects of putting the deep cycle battery with the the car battery? I want to try it but don't know if it will cause any damages to my setup.

They are both flooded cell batteries, so they voltage should match fairly well, nothing bad should happen. However as stated, a car batteries are made for short bursts. They last a while if you keep them above a 90% state of charge, not so long if you take them to <50% SOC, so paralleling the car battery with the deep cycle will just wear it out quickly. Deep cycle batteries are happy with deeper discharges. However no lead acid chemistries like to stay discharged for a while.

Are these lights used for you or the chickens? (I.E. used just for a bit when youre in there, or are they meant to run for a while? I'd imagine its the former... )

5x 23W lights is 115W, with inverter inefficiency call it 130W load presented to the battery, or ~11A draw. A 45Ah battery will be rated for a 10 hour discharge, if you draw faster the battery looses capacity by the peukert effect (more losses though this than internal resistance) meaning you might only get 11A for 2.5-3 hours before its dead. On some batteries, a 1 hour discharge can almost half the effective capacity.

And with a 5W solar panel, you'll get ~.4 A, meaning it'll take 40+ hours of full sun to charge.

 

[deadrx7conv]

Fixed lighting forum!!!

5w solar panel, along with charge controller, is what I use/recommend for keeping batteries trickle charged when something is not in use, like the motorcycle,convertible,boat,RV.... winter storage. I wouldn't ever use it to or expect it to charge a couple 35lb-50lb batteries.

I recommend 3-5 watts of solar panel for each watt of light you want to run(dusk:dawn) setup. I recommend 1ah+ of battery for each watt of solar panel.

The 5x23w incandesant lights can be replaced with ~5w LED or CFL lights saving a considerable amount of power. And, you should be able to find some that run directly of 12v(RV, boat, auto accent lighting...). Get rid of the inverter.

2 batteries are better than 1. But, when you buy your deep cycle battery, make sure its big enough on its own. If you run that automotive battery down too much, you'll kill it quickly. But, parrallel, if you have surplus amps, shouldn't be a problem. I have a friend at the local salvage yard that brought me several 'start' batteries and in parallel, they work fine. As long as you don't discharge them too much, they'll last a while and then you can recycle them.

Harborfreight has a 45w panel and some 12v CFL lights. Just add battery. I don't remember what the bulb wattages was, but you'll need 3 of these to do what you want, along with a deepcycle 45ah+ battery for each. http://www.harborfreight.com/45-watt-solar-panel-kit-90599.html This gives you an idea on how much solar panel you need for what you want to do. The harborfreight kit is a simple system to copy and upsize for your needs.

 

[[email protected]]

The light

 

[[email protected]]

The light was initial for my use. Now I'm trying to figure out if I can get it to work for the chickens. I want the light to be on about 4 hours a night to see how it will effect the chickens, but for now it's just for about 30mins of usage per night. Thank you.

The light was initial for my use. Now I'm trying to figure out if I can get it to work for the chickens. I want the light to be on about 4 hours a night to see how it will effect the chickens, but for now it's just for about 30mins of usage per night. Thank you

 

[deadrx7conv]

Are the chickens afraid of the dark?

If you want to give them night lights, consider some 'lawn lights' like:
http://www.lowes.com/webapp/wcs/sto...oreId=10151&catalogId=10051&productId=3265261
http://www.lowes.com/webapp/wcs/sto...oreId=10151&catalogId=10051&productId=3316668
http://www.homedepot.com/webapp/wcs...talogId=10053&productId=202519714&R=202519714
http://www.target.com/Philips-50ct-Powered-String-Lights/dp/B003BIJ8FQ