Im creating a Tripod Light System for night work, specially for the volunteering work I do, called SES in Australia. It will have battery pack so that it can be easily setup without generators.
I have chosen to use six XHP-70 for the bloody beam and great lumen output. I don’t plan to over drive them to keep heat generation low.
My first question is: What are the advantages of using a 6 volts or 12 volts XHP-70?
The battery pack will be created using multiple 18650 li-ion. So the voltage can be built to the requirements of the driver.
Once the LED setup (6 volts or 12 volts) and the driver is chose, I will need some advice on where to get them from. Good reliable stores.
The XHP-70 should be on sink pads and will be attached to an aluminium heatsink.
2. Drivers for the XHP-70. The drivers can be: 1 Driver per XHP-70, 1 Driver per 2 XHP-70 (in series) or 1 Driver per 3 XHP-70 (in series if this is possible). What drivers out there are good and reliable for this? I was planning on using the Convoy L6 driver, one for each led. But what are good recommendations on drivers please.
Keep in mind its not a flashlight so drivers do not need to be round and small to fit in flashlight bodies. I require good quality, reliable and if possible the best lowest prices too.
I think that sit for now. I will possibly update this post as times goes.
The advantage of 12v over 6v operation is that the current can be lower and still obtain the same wattage. You can use thinner wires and the driver shouldn’t have to work as hard to provide the current. The advantage of the 6v operation is the traces are larger on the mcpcb and thus you can pump much more current into the led. Usually the 6v is reserved for flashlights as it is usually easier to have 2 cells in series instead of 4. I think for your application, the 12v option might be better since you’re planning on using a battery pack to power it all. Heat shouldn’t be as much of an issue if you aren’t going to drive the LEDs very hard.
Cool thanks for the explanation. I didn’t think about thinner wires, its a good point. I only though in regards to less stress on on batteries to deliver the higher current.
Because i remember looking on their website about a year ago. But i had forgotten there was a store in Australia that sells these parts. Most times,my subconscious is to look for stores overseas, they normally have more variety and are cheaper.
Bruno28, seems to me you're a gnat's ass green on these matters. In no way I am wanting to discourage you with regards to building the ambitious tool you want to craft but seriously, don't you have some close buddy/workmate/electronics shaman willing to help? :-)
With regards to your question about voltage: P = V × I, P = I² × R, which means the power loss on the wires/contacts/switches/tracks/etc. is proportional to the square of the current crossing them. Thence it is advisable to use a higher voltage (and a lower current, or else power wouldn't remain constant) wherever possible in order to minimize losses if this is of relevance.
The stress on the batteries is solely relative to the amount of load you set on them: whether you drive your XHP70s at 6'25V × 4A or 12'5V × 2A will only be of relevance for the driver's DC/DC conversion efficiency and the losses on the conductors from it to the leds.
Suggestion: some sort of 8SxP bigass battery and a a proper BMS with balance (or a BMS witbout it plus balance boards); I'd also add an additional balance board or two to that unit, too little balance current for my liking as you are going to build a BIG battery.
I got these drivers from russia. They can run 6-12 volts 4.8 amps so it will be two led in series for every driver. But the seller said that it can burn if i use 12 volts XHP-70 in parallel (2.4 + 2.4 amps).
Should I go option 1 or 2?
Option 1: 2x XHP-70 (12volt) in parallel with 4.8 amps
Option 2: 2x XHP-70 (6 volts) in series with 2.4 amps
I don’t want to use one driver per led. But these are small and seem to what another member her used for his light bar.
I need to order the XHP-70 tonight.
Well, those LDRADJ29s do not seem bad. The seller told you they would burn by driving two in-series XHP70s (12+V) at 4'8A because that driver just cannot handle such a load (60+W), seems to be designed for 30ish watts.
So, you'll need 12 emitters and 6 drivers for efficient 20000 lumens light source, 2 emitters per driver. Wether you set 2 “6V” emitters in series or 2 “12V” in parallel is electrically equivalent, though I would go with the former (simpler emitter baseplate).
Bruno28, how space constrained are you planning to be with regards to driver housing? Bear in mind you'll have to attach those flashlight drivers to a heatsink, or else they'll die rather quickly…
I'd choose stuff like this instead:
As you can see o the attachment photos of the CAD, it will be all aluminium, so its a lot of heat sinking. The drivers will be attached to the casing and i will thermal paste it to help with conduction of heat.
I have one of those boost converters for my 100w COB, but its wayyyy to late for the unit I’m building. Wouldn’t be able to make it fit into that head.
Also i have decided to go with 6volts, as someone reminded me that if one led dies, then the series shuts off and not all the voltage/current goes through one led and burn it. Something I forgot to take into account.
Yeah I’ve seen that. Ive spoken to him and he has given me some assistance with things like the driver and heat sink. It is a bit similar. Mine will be pure flood as it will be a working night light and his is more for 4x4 vehicle with lots more throw.
Latest Design. This is iteration 4. More thought out, groove for glass to sit on and be pressed by the front face.
Also included cable tray for organised arrangement of wires from outside to drivers, to led.
Cycle at the back face is for the driver housing. The main body will also be the heat sink for drivers (3 drivers) and the led.
Material will be aluminium for body and heatsink.
I am going to put the flame suit on here
but for the intended purpose why not grab a couple of cheap light bars from ebay
you can run them straight from a car battery or genny with 12v output.
available in a huge variety of outputs floods and spots.
I realize its not modding or constructing just economic
Reliability….ebay cheap lights are Chinese with low quality control.
I’m creating this to use as a substitute for the current lightening system. At least it will be a massive improvement to what we use at SES. I’m using good materials and electronics. Efficient LED and one of the best Tir lenses for xhp-70.
I want to make a few and sell to local fire and rescue and other rescue agencies.
Also this is only the light you’re looking at it will have a Power bank and be able to run 100% for 3 hours without the need for a generators. Generators are time consuming to setup and very loud, which interferes with communication.
Also as an engineer I wanted to create my own lighting system. Been waiting to do a flashlight for a while and I thought this was an opportunity.
The main goal of this project is:
Provide improved lighting system with Reliable operation
Easy of use and setup (under 60 seconds)