How to... Always on LED Light Setup?

P

Petec

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Hi All,
Need yer brains :)
I'm looking to install the following setup:
12v Charger to 12v Battery to 2x 12v LED Lamps

I want this to be always on/connected, and to just flip the switch when there is load shedding and need the lighting.

Is my thinking correct with regards to the wiring?
TIA

led-light-wiring.jpg
 
yes as long as you arent using that particular charger ,you need fuses and ideally an undervoltage cutout and not really a small battery 18ah minimum
 
The battery bms can do low voltage shutdown when depleted (though might need a jump when power returns with a smart charger that doesn't charge if battery isn't present)
So always nice if you buy capacity that would prevent running it down to shutdown o

How many hours would you need

If 20w leds you will use 3.125AH per hour of runtime
 
wingnut771 said:
What’s wrong with that charger?
Click to expand...
Also asking this.
Coz I researched, and the only other decent LiFePo4 charger I could find on Takealot, is the Victron Blue Smart:

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leon.davibe said:
The battery bms can do low voltage shutdown when depleted (though might need a jump when power returns with a smart charger that doesn't charge if battery isn't present)
So always nice if you buy capacity that would prevent running it down to shutdown o

How many hours would you need

If 20w leds you will use 3.125AH per hour of runtime
Click to expand...
Only gonna need 2-3 hours runtime.
 
Petec said:
Also asking this.
Coz I researched, and the only other decent LiFePo4 charger I could find on Takealot, is the Victron Blue Smart:

Takealot.com: Online Shopping | SA's leading online store

South Africa's leading online store. Fast, reliable delivery to your door. Many ways to pay. Shop anything you can imagine: TVs, laptops, cellphones, kitchen appliances, toys, books, beauty & more. Shop the mobile app anytime, anywhere.
www.takealot.com www.takealot.com
Click to expand...
I wouldn't bother with an LFP charger for this setup, just get a lead acid charger.

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South Africa's leading online store. Fast, reliable delivery to your door. Many ways to pay. Shop anything you can imagine: TVs, laptops, cellphones, kitchen appliances, toys, books, beauty & more. Shop the mobile app anytime, anywhere.
www.takealot.com www.takealot.com
 
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Which is best Way to Charge LiFePO4 Battery？

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lkpat said:
www.bravabatteries.com

Which is best Way to Charge LiFePO4 Battery？

LiFePO4 battery continues to dominate the battery storage arena in 2023 thanks to their high energy density, compact size, and long cycle life. If you’re looking to prolong your battery life while still maintaining its performance, then knowing the best ways to charge a LiFePO4battery will...
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Click to expand...
The charger I posted according to the comments keeps the voltage at 13.8V so will be stress free for the battery. It may charge a bit slower due to the lower voltage but at R300, it’s worth the experiment. You should avoid chargers that keep the voltage at 14.6V forever.
Spending R2k on a charger for a R500 battery is not necessary imho.
I’m also not sold on the whole you mustn’t float an LFP or use pulse charger. LFPs are hardy mofos imho.
 
Petec said:
Only gonna need 2-3 hours runtime.
Click to expand...
Yea the 9ah would give that 2 plus and just fall short of the 3 if both are used 100% of the time (if 20w led x2 ) if less watt then more hours of lught

If you have an old laptop charger lying around a buck converter turns them into a nice CC/CV charger no float though so you can just unplug when full otherwise it will float at charge voltage

The charge rate is much quicker than a car battery charger that tapers the amps as the voltage rises
 
Last edited:
I have something similar in the garage, 2 x 12ah lead acid batteries and 2 x 7watt led strip lights. Nearly 3 years now and still runs perfectly. El cheapo charger.

My only suggestion is to get a good switch as many dont seem to last, a minimum rating of 2A in your case, assuming a total load of 20 watts/
 
Maybe the charger wont have continuity when the mains are off so the lights wont work.

IDK, just spitballing.

PS, why not use a decent sized car battery?
 
Rickster said:
Maybe the charger wont have continuity when the mains are off so the lights wont work.

IDK, just spitballing.

PS, why not use a decent sized car battery?
Click to expand...
Don't need the charger as the lights have parallel correction to the battery and will be powered.
 
I assume for outdoor use
Can it for indoor use i find the 12v led down lights makes for a clean install

That wat you can lay the wire in the ceiling and just have it come down where the. Battery is
 
leon.davibe said:
I assume for outdoor use
Can it for indoor use i find the 12v led down lights makes for a clean install

That wat you can lay the wire in the ceiling and just have it come down where the. Battery is
Click to expand...
You can't run long wire runs with 12V afaik, too much voltage drop.
 
soulie said:
thats an optimate 2 charger ,which is a battery maintainer and charges at a max rate of 0.8 amps .they do a great job on long term standby batteries but dont charge quickly .
Click to expand...
How could you tell from the pic? There are many flavors of that charger.
 
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