I’m looking for a 3k+ lumen light that can run off of a 12v automotive battery. It will be used for navigating a river while checking lines. Any suggestions would be greatly appreciated 
Is there any reason why it can’t use lithium batteries? Or you don’t want to carry spares with you? Most of the 3k lumen lights I know go through about a pair of batteries per hour roughly.
I didn’t realize a light that bright would last that long on a pair. I’m open to any recommendations.
If you really want a flashlight type solution, I would just look for any 3k lumen light you like (one that really is 3k) that runs on 4.2 or 8.4V and buy a cheap buck converter (edited: I said constant current, and those come usually with voltage and current limits, but you only need voltage control if you keep the driver in the light. If you gut it and wire straight to the led's, you'll want current control) off amazon or aliexpress. FYI the BLF Q8 is being made with a tripod mount, and there is a buck converter being thought about for it, but that will require modding. I would also say any LED with a decent tint should go through closer to 3 18650 batteries in an hour if it's really 3k lumens. The thing to watch for is if said light can do it continuously without overheating.
On the otherhand, you could also just buy a pair of these:
Put a couple of 75W MR-16's spot bulbs in it and you'll probably be well enough over your 3k lumen target with a pretty cheap and easy setup and a nice hi-cri warm tint.
or this:
(don't know if you can adjust optics)
You have a car (jeep I guess). You don't need led's or flashlights. I'm sure there are a ton of driving lights you can find easier. Isn't the usual solution to mount like 4 of these on top:
I navigate the river with a 16 foot johnboat not a car lol.
Ah of course, not sure why I thought that, just had it in my head already when 12V came up. Anyway, you have 12V, so it's the same. I guess you might be limited in battery capacity still though?
Not exactly. I don’t have a charging system and have run down a full size automotive battery with my Q-Beam more than a few times before the night was over.
I may look into a couple of smaller light bars.
What about one of those big incandescent handheld spotlight/flood lights, normally have a pair of crocodile clips or a cigarette lighter plug.
Uses a h1 headlight bulb?
Remove h1 incandescent bulb, fit a 55w or 35w hid kit for a motorcycle ($9)
Works great and whilst not as efficient as a led, it last a long time on even a small automotive battery and it’s mega bright
Hmm.. might need to look into lithium ion batterry packs. They cost more, for a big one, but carry a bunch more power and less weight. I looked for automotive spot lights recently in the class you're looking at and didn't come up with much at all. There are no 12V flashlight-class or bike-light systems, and automotive led systems are either crazy expensive and/or not very good as far I found. I'm interested if you find something though.
As far as the battery, if you need 3000lumens for long time, which it sounds like you do, maybe look into RC lipo batteries. Like here:
This is probably your least expensive option at around 0.40 $/Wh.
Not 3000 lumins but Ilmn has 12 volt light pods on sale for $15
You know it strikes me that you might be able to direct drive 12V XHP35 emitters off of SLA, especially if you use enough of the emitters. I don't know that much about them, but looking at some lead acid voltage curves and some of their voltage curves, it looks maybe possible. Some SLA curves I find drop voltage faster than others and it may depend on the quality of your battery. Also those are big emmitters, and you might need big optics to make a good spot. I have no idea what exists in this format already. The Q8 comes to mind again(probably because I don't know that many other things), but I suspect it won't throw well with those big emmitters. The SRK wasn't ever really a thrower in the first place.
Do you have a link?
I’m not sure I could put something like that together.
It doesn’t have to be a huge thrower, ~100 yards would be plenty.
Many years ago when I had a similar need to yours I had on hand a Marchal pencil beam driving light using a 100w H2 bulb. It was easily more than what you require. I drove it from a 12v 6amp charger only because it was the easiest way to do it for my application. I drilled out a handle and just threaded it onto the bolt that was intended to connect it to the automobile. That was easily over 30 years ago. I’d be very surprised if one couldn’t come up with a solution from an auto parts store or Amazon that could best what I cobbled together from what I had on hand all those years ago.
But today I’d just get a L2 and carry spare cells. On high output with two 5200mah cells should run it for 3 hours. You can deal with the heat by putting a wet rag on the head. Or if medium output would be sufficient with intermittent Hi output I don’t think you’d have heat issues and on medium those same 5200mah cells would run it for 11 hours. I’d tie the light to a milk jug just in case it went into the drink. Might even put a small light in the jug and turned onto moonlight mode to make it easier to find. Of course it can also be used with a wrist lanyard or a sling if that won’t get into the way.
… (pitter patter of returning feet) I just now tested a Convoy L2 and it will easily reach out 100 yards on medium output. I’d still carry spare cells though and I’d use the extension to allow the use of 2 cells in the light.
I don’t know of anything LED off the shelf but you could put together something yourself. An HID with a 12V ballast would work as well, probably need 50W or higher. Just judging by eye, I’d guess a regular Q-Beam would be around 1500 lumens, maybe slightly more. I don’t have the Black Max version though, all mine are the older style you’ve probably seen or used a million times.
I have this exact project going for the exact same reason, it’ll be closer to December before I can get them finished and a build thread posted though. I’ll be using a generic 52mm LED “spotlight” off eBay, its small compared to a Q-Beam but has a large heatsink compared to similar sized lights. I’ll be using an XHP35 initially, but will switch to an XHP50 or XHP70 if it’s not bright enough.
I would suggest finding a driver with either multi-levels, a pot for adjusting current or a set resistor that could be used with a rotary switch. In my opinion the the rotary switch is the best option. With the pot you can adjust the output, but there is some “free-travel” where you’re turning the switch but nothing is happening. I’ll be ordering more pots with different values to try. If I can eliminate the free travel this would be the better option. As it stands now, a rotary switch with three positions wired to the set resistor would probably work better. You could simply turn the switch to the desired brightness without having to cycle through the levels.
If you’re running the battery stand-alone, without being connected to the engine alternator, then most 3 cell drivers and even some 4 cell drivers would work. It gets more complicated if you’re using the battery connected to the alternator. With the engine running you sometimes get spikes in voltage which will fry some drivers.
I’ll be running the XHP35 at somewhere just over 20W, which will give me an output around 2300 lumens. With an efficient optic and good heat sinking that should be good for 2000 OTF lumens.
One other thing, I’d also incorporate something to cut the input should the temps get too high, for protection of the light as well as yourself. I had an incident once where one of the girls with me got excited an an “event” that had just transpired and simply laid the light on the truck seat facing down instead of turning it off, we walked back up on a truck cab filled with smoke. I though the it was on fire at first, relieved it turned out to only be a burnt bench seat. Lesson learned, people do dumb stuff when they don’t understand how things operate.
Let me know how you’re hooking it up and I’ll send you some driver and host links.
-Michael
EDIT: For instant gratification, you could probably just mount a handle on some of the smaller 12V LED “work lights”, the ones that have 4 emitters. They’re about $25 a pair. Now that I think about it, I might be spending more time on this than necessary, buying one of those with actual Cree emitters and swapping the driver would be a quick solution.
EDIT 2: Here’s one with 6 emitters ,had a friend who had these on an ATV. IIRC they used Cree XP emitters. Re-wired into a 3S2P @ 1A each would be about 18W and close to 3000 lumens! I might have just talked myself into trying one of these and reflowing some XP-G3s with a new driver.
Does it need to be led? I would recommend hid. A generic ebay 85w hid flashlight will get you more than 5k lumens for over an hour and I have used mine on a boat many times, it literally lights up the entire waterway. The battery packs that run them are 12.6v so you could wire it directly to an external marine battery for longer runtime.
Also, if your crafty, you could buy an automotive hid kit and some automotive housings and install them on the boat or a rotating mount. You could source headlight assemblies from a junkyard, even the old reflector type would do the job but of course projector type would be nicer. Hid retrofit kits are available as low as $35 a set and even a generic 35w set will get you more than 3000 lumens. The possibilities are endless and you can do it as cheap or expensive as you wish. 4300k color temperature out on the water is truly a sight to behold!
Are you using a full size battery to run your Q beam. I used to run the river a lot and ran an aerator and a Q beam on the same battery and never ran one dead. Maybe you need a new battery. Sure you are going for flathead/appaloosa cats, did it every Friday for about 3 years straight in the early 90’s. My biggest was 42 pounds but my friend got one 88 pounds and several more over 70 pounds. I would stick with the Q beam because led lights with built in batteries aren’t going to last you long enough unless you carry several extra sets of batteries. Another option is the Streamlight Litebox, it will last a long enough time but won’t be as bright as the Q beam. Make sure your battery is deep cycle, made for extended low draw applications, last much longer than regular car batteries.
Very good idea. Won’t give you much in the way of throw but lot’s of light with a pair of them and an inexpensive out of box solution. :+1:
Caught me typing, here’s the EDIT from above,
EDIT 2: Here’s one with 6 emitters ,had a friend who had these on an ATV. IIRC they used Cree XP emitters. Re-wired into a 3S2P @ 1A each would be about 18W and close to 3000 lumens! I might have just talked myself into trying one of these and reflowing some XP-G3s with a new driver.
Those are $15.99 a pair, less expensive than a single one of the large heat sink single emitter type I was planning on modding! They’re IP67 rated as well, think that’s 3ft of submersion for 30 minutes.
IIRC the XP-G3s are around 500 lumens driven at 1 amp, so 3S2P at 2A would equate to 18W and close to 3000 lumens. I’m off to check the Cree PCT and verify my estimations.
One downside I can see right off is those are the exact ones he ordered, I remember them being genuine Cree emitters, but instaead of optics the used reflectors. Alsmost every reflector I’ve tried to date with the XP-G3s have resulted in that ugly corona/hotspot color differential.
They do have a spot version, not sure of the FWHM though.
-Michael
For checking limb lines you need something with throw, floody lights are useless.