Headlights On Yerf

[steeze]

so, i have a 30033 yerf dog cart, im looking to put some off road spotlights on it that i found on northerntool.com. i realize my Tech. 6.0hp does not have a generator on it, so im planning on using a separate battery.

here are the lights: http://www.northerntool.com/shop/too..._352679_352679

so i dont know much about batteries but i found some that are in my price range on northern tool

like this onewill it work?)
http://www.northerntool.com/shop/too...0378_200390378

now i understand i have 12 volts, but what about amps? is 7 enough to power 2 of the lamps above?

please help!!! how many amps do i need?

thanks!!!

[metalstudman1]

Any lights would work- the ones you've picked are plenty bright enough. The battery isn't anywhere close, go get a lawnmower battery at Walmart for $20. that has 160+ amps or spend a little more for one with 200+ amps. You'll need a battery charger (trickle charger) to go with all this to keep the battery charged after each use.

[steeze]

ok, thanks a lot! how long would a 160 amp last powering a pair of those? and i have been looking at chargers, hows this one? http://www.northerntool.com/shop/too...6086_200456086

oh yea, and is it at all possible to use a deep-cycle batt? i dont like all the dangers of lawn mower batts

[metalstudman1]

Our last kart with a 165amp lawnmower battery that we rigged up with 55watt lamps would go for about 2-1/2 hrs max. it was used with the lights about 50 times before we retired the kart.The deep cell battery would be the ideal battery but don't know of a kart size one out there though.
What dangers are you talking about? they're sealed just like the ATV specific batteries and pose no more hazard than any other battery.
The charger will work perfectly-you might find it a little cheaper elsewhere.

[uthe54]

heres how you figure out how long the battery should last.

a 55 watt light bulb on 12 volts is about 4.6 amps (watts divided by volts, eg55/12 = 4.58333). In theory, if you had a battery rated at 4.6 Amp Hour (Ah) you could mathmatically run the light for 1 hour. If it were a 9.2 Ah battery, it should run for 2 hours, etc.

now I say should for three reasons.

Reason 1 - just like in a flashlight, the light starts getting dark way before the battery is low. thats because the voltage is decreasing as the battey is begin drained, thus the amount of watts supplied to the light is decreasing. the Ah rating is (my understanding at least) when the bulb is completely out.

Reason 2 - it's extremely hard on a lead battery to discharge all the way. I think I remember reading somewhere that a car battery can only completely charge and discharge a small number of times - like 10 or something. A deep cycle/marine battery is supposedly better at withstanding full discharges, but it's still not good for them. I think once a lead battery has discharged to about 70% capacity, it starts to damage the battery.

Reason 3 - This is the rating of the battery brand new. obviousally as the battery is used and recharged, it'll lose its ability to hold a full charge.

With all that in mind, if you get something like say a 100Ah battery, you should last 21 hours in theory. multiply it by 30% (.3) and you get 6.3 hours to put the battery is at 70% - which is when it'll need to be charged without damaging the battery.

also note, Ah is not the same as cranking amps. For example, the batteries in all my buggies are 90CA, 9Ah - obviousally built for starting the buggy, and providing a buffer for the headlights/whatever other electronics are onboard - not for running headlights with no generator.

sorry for the long post. I hope you learned something.

[steeze]

so in your last paragraph, you're saying that lawn tractor batteries with a high CCA are not ideal for headlights? how do i find one that is?

and i know this may sound stupid, but i thought most batteries were supposed to be ran down to nothing before recharging to prevent memory, or is just that a certin kind?

(as you can tell, i dont know much about batteries!)

[uthe54]

I think you want to look for a deep cycle lead-acid battery. They supposedly handle being discharged better than a typical SLA (sealed lead acid) would. You want to find a battery with a high Ah rating - ignore the CA/CCA rating since you won't be using it to turn any starters. use the math I described earlier to get your desired headlight runtime, and then you know what to look for. I think deep cycle batteres are more expensive than traditional SLAs though.

Different types of batteries are maintained differently. NiCad/NiMH batteries (often found in power tools and some digital cameras) do have "memory effect" so its better to cycle them down completely before recharging them. This is not the case with Lead Acid batteries. Think of your car for instance, your battery ideally should never discharge lower than 90%. It just provides a burst to start the engine, then is instantly recharged with the alternator. car batteries last about 5 years doing that. If your lead battery had a memory effect, it wouldn't last long treated that way. Also, I'm sure you've had instances where you left your car headlights on by accident. It's amazing how that can kill your battery. Why? Because the battery wasn't designed to sustain current for a long period of time - plus because your starter needs a pretty good chunk of power to turn over - a battery discharged 50% of the way makes a noticable difference turning over an engine.

The better type of battery are lithium batteries. These are typically found in cell phones, laptops, and higher-end power tools. Lithium batteries have a very low self discharge rate, and can provide full voltage until it's almost dead - which is why laptops/cellphones can still run with 3% battery life, yet a flashlight can hardly run if it's battery has only 3% left. They also are pretty decent at providing bursts of power, and have no memory effect. The problem is lithium batteries are more expensive, and I'm not sure one exists that will do what you're looking for - running your headlights. Oh - one other advantage is lithium batteries are light - unlike lead batteries where weight usually isn't too big of a concern.

I could go on forever on this topic... I like discussing this stuff, but I think I answered your question.

[steeze]

Thank you, and yes, you did answer my question.

after looking around for tha batteries you recommended, i found they were all very expensive and/or too big. are there any you would recommend if im only looking to spend $40? or am i being way to cheap? it would need to power 2 55w 4.5amp bulbs. and i wouldnt run them for any more then 45 mins. at a time, b/c i would run out of gas.

[uthe54]

How many times do you intend to cycle this thing? If you're just going to use it a few times per year, then who cares if your battery can only handle 10 or so full discharges... espically if it has a 2-year free replacement warranty . In that case, I'd just suggest getting a cheap lawn tractor battery, or probably even better - a 17Ah UPC battery. I think you can find thoes as cheap as $20-30. Harbor freight sells a car jumper unit for between $30-40, and it has a 17Ah SLA in it... you could buy that and yank the battery out of it...

However, if you're thinking you're going to cycle it every night, you should probably do it right.

One thing that comes to mind is a powerwheels battery. They are deep cycle, and relitively cheap. Since you're wanting to run 9amps (2x4.5 amp bulbs) for .75 hours, then the battery would be 100% depleated if you had a 6.75ah battery. in theory, a 13.5ah battery would be at 50% after 45 minutes of runtime.

If I were your, I'd just get a cheap lawn tractor battery from walmart, since I've only actually been out at night once with my buggy, and I probably only ran my headlights for half an hour. However, we are both different - you might like to ride every night...

I came across this today also BTW, which seems to be a pretty good read. This agrees with what I said about deep cycle vs lawn tractor batteries. You may learn something here too.
http://powerwheelscd.com/images/gard...batteries1.pdf

I haven't looked at prices of the powerwheels batteries, so I don't know if they fit your budget or not, thats just something that came to mind.

[uthe54]

one more thing... just a safety reminder, regardless of which battery you choose, install an inline fuse. One probably came with your headlights, but make sure to install it. If you're using a lawn tractor battery and you have a short with no fuse, you could have a mess on your hands with the high CA ratings on thoes things.

[steeze]

thanks soo much for your help, i only would ride at night like once a week or so. i found 2 12v 12ah batteries laying around, so im gonna try to use one of them first, and if that doesnt work too well i will go for the lawnmower batt.

now i batter get going on this project! thanks for all the help!!

[uthe54]

Not bad! I love it when I find that kind of stuff lying around!

depending on the age of the batteries, they might not have 12ah capacity anymore, but still, free is hard to argue with.

One more thing, you might check to see if you can use them in parallel, which would give you 24ah. In parallel means you connect both batteries + posts together, and both - posts together. BE SURE to do it this way. Connecting the + on one of the batteries to the - on the other is running in series, which will double your voltage, which will quickly burn out your lights. Running in parallel will keep it at 12V - which is where you want it.

one word of warning though, the battery will only be as powerful as the weakest cell. lead batteries generally have 6 cells, and if one is bad, that one cell will discharge all the other cells. That said, if you have 2 lead batteries running in parallel, and one of the cells is bad, it will actually discarge itself and the other battery. Running two batteries in parallel effectivly double the chance of a failure since now you have 12 cells that have to be maintained.

In other words, it's not good to run batteries in parallel unless they are exactly the same, and have been used for the same application for their entire life. An example is a UPS battery (UPS meaning thoes heavy things that run comptuers when the power goes out). Some of the bigger units use multiple batteries in parallel, so if thats how these batteries were used, you are probably safe running them in parallel also.

one way I know of to test to see if the batteries are compatible with running in parallel is to do this. Hook both negative terminals together on the battery, then use a multimeter set to amps, and connect both terminals of the multimeter to the + posts on the battery and see if any current flows through. If the meter reads 0, you're okay, however if the meter says anything, even + or - .01 for longer than a few seconds, then you know one of the batteries is pulling current from the other, and will eventually discharge the cells.

If you can't tell by now, I'm partially a battery nerd .

[ckau]

Originally Posted by uthe54

If you can't tell by now, I'm partially a battery nerd .

It's good to have a battery nerd on board with the problems we experience with batterys and charging systems.
I have always felt the man who invents a practical, substainable battery for interstate travel will one day, be able to tell the oil barons where to get off and end up ruling the world.

[gunluvinfull]

How many CCA would I need to get my old Swatch up and workin again? The dang thing ain't told the time since the 70's. Would a Power Wheels battery do the trick? Also it glows in the dark so how many watts is the ole Swatch eating up if I push the night lite button like 3 times a night?
Very good info on Batterys. I needed the info on Parallel and Series again, I forgot it.
Thanks

[gunluvinfull]

What I don't like about my Spiderbox is how they (headlights) just come on when ya start it. I am gonna redo that with a switch and when I get my other lights they will all be switched too. Lights that come on when ya start it just strains the battery. I don't like things on if I ain't using them, Ya know? waste of good electricity. Hell it's big and red like a hunter in the woods if ya can't see it comin w/o those 2 dinky headlights on top, ya ain't gonna see it at all! Also I read where a dude took his brake safety switch and switched the wires to make it a brake light. It in my opinion would be much more useful for that. I intend to do that also, with 2 brake lights in back and 4 yellow lights,2 up front and 2 in the rear.

[GX150]

The lights are powered directly off stator AC voltage and do use the battery. If you have the stock 35w bulbs, the battery will continue to charge while the lights run.

[gunluvinfull]

So if i do buy one of those cdi boxes is the one I need ac voltage also? I don't understand the ac voltage thing on the spiderbox. how does it convert dc volts to ac volts the stator is ac volts or what?

[GX150]

The stator produce AC voltage. Light bulbs don't care if they are powered by AC or DC as long as the voltage level is correct. There is a dedicated lead to power the CDI with AC voltage. The 6-pole and 8-pole stators have a 2-phase AC output through a 4-pin connector that runs to the rectifier, choke and lights. The rectifier converts AC to DC voltage so you can charge the battery. The battery's only purpose is to power the starter motor.

[gunluvinfull]

very good to know so if I buy one of those performance cdi boxes I need the DC box right? with the 4 pins, the other ones the ac cdi is used, are used on the scooters, am I correct? Thank You for the info. I know its already on here but I am to lazy and old to look!!! LOL

[GX150]

No, DC powered CDI's are for buggies that wired differently than yours. Whether it is a scooter or buggy, the engines are the same.

[gunluvinfull]

I am really confused now!!!

[GX150]

The CDI is for your ignition and can either be powered by DC or AC dependent on the engine wiring. The rectifier converts AC stator voltage to DC voltage.

The choke can run on AC or DC as long as the resistor is inline with either. The CDI must be a DC version to run on DC or and AC version to run on AC (applying the wrong voltage will burn up the the CDI). The battery must be charged using DC. The starter motor and solenoid require DC to function properly The lights can run on AC or DC without a problem.