Thanks for the link Flashpilot, but I have some drivers en-route to me for testing, a boost driver with thermal and short-circuit protection, from Sure Electronics.
Here is my revision of the light bar… I decided to simplify the design and go with the superior flood optic, and also it will have 5 OR 6 spot optics. Total Candela output (with 6 Spots) moves to ~580,000Cd from 380,000Cd, and 25000 LED Lumens from 20,000 LED Lumens.
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Really excited to see how this shakes out!
You really opened a whole new style on designs with the XHP series. In sets of 2 or 3 for side and rear mounting. Whole single row bars with maybe 6 to 20 large LED’s without the goofy 2 high stacked xpg clones in 100 LED Chinese light bars. LOOKING GOOD!!
Oh it’s going to be good. I am a bit behind with my budget at the moment so it will be be in the new year before i get a prototype built. I athink i am going to make an external driver enclosure, it saves trying to cram everything inside the bar, and simplifies wiring as only a 3 wire is needed into the bar. I lose thermal protection, however.
Well these things are just plain big, bigger than I expected them to be, but that is okay as I will be making an external box enclosure for them, and in this case, they are no longer too big. 4 times the footprint of the old drivers, however not a fair comparison as these are rated for 50 watts and the Russians are ‘designed’ for 30 watts, I was pushing 38 watts through them, they make a buzzing ‘switching’ noise though.
Dimensions are 3 inch x 2 inch and 3/4 inch tall or 50mm x 75mm and just under 20mm tall.
I will rig them up and test them out to see how they handle 48 hours of torture. :smiling_imp:
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Well I tried one of the drivers on the light bar for a bit, works great… went to wire up another in parallel, and poof went the second one. Why? I checked and checked my wiring (pretty simple!) for reverse polarity but I found no issue.
I need someone with more knowledge than me on this, can you drive two current regulators in parallel? I have done it no problem with the russian 3 amp drivers, in fact a 3 amp and a 2.4 amp driver in parallel. I know you can’t wire two voltage regulators in parallel, such as a computer PSU as there is always a difference in voltage between the two units which makes it non-compatiblein this way, but you can wire them for series operation. I think this is opposite when we are dealing with a current regulator such as an LED driver.
My conclusion: Either you cannot wire two boost regulators in parallel for some reason that I fail to see, or this was simply a dud driver and I want nothing to do with these then…
Transistor right in the middle of the board went poof.
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It is not good idea to parallel output both on buck and boost circuits.
Once you get the drivers figured out, would you consider potting them for vibration resistance? It seems like this would be an optimum application for that, otherwise all those little caps would just wiggle and fall off sooner or later.
That is exactly what i will be doing. Or using a thick silicone conformal coating. I might just want to get the custom made circuited DTP mcpcb board, that would be nice at this point.
Driver has been running 4 xhp-50 6V in series for 12 hours now. Temps took about an hour to hit equilibrium, with the inductors being the hot spot of 60+ C (140+F).
I am tempted to test their 100watt 3 amp BUCK driver, looks to be MUCH small (half the size), same price, but it would be running at less than half the rated output, might help for temps… and obviously packaging. The light bar just won’t have the 100% power output at any voltage. We will see.
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You probably shouldn’t parallel switching regulators unless they specifically mention that outputs can be paralleled.
Looks like only the MOSFET is damaged though, so if you replace it it may be salvageable.
Are you being flexible on LED selection or driver modes?
I saw the link to DIWDivers led driver, but also note his last forum activity was a while ago… His driver seemed very good, in terms of both power output and affordability.
Very interested to see where the rubber finally meets the road.
For a ~$400 outlay, cast my vote for 4k color temp and either/or Hi/Low with both flood and spots, or select flood/spot/flood+spot.
Amazing work, guy. I love projects like these.
I checked it out, but I am not interested in that for this project. It looks like it is going to be a custom made copper DTP boards with integrated drivers or this Sure driver in a remote driver enclosure. Thanks for the comments.
Not sure when they will be available from Cutter (just emailed about it), but I am eager to to use the new XHP-50.2 K2 binned 5000k emitters in the new setup. 1200+ lumens at 1400mA (6v)
Cool news about the new binning option! It seems like they’re moving forward quickly with new emitters.
I really like the idea of the custom DTP board with integrated drivers. How much complexity do you anticipate that would add? It seems like there are plenty of qualified people on this board who have designed drivers before with great success, and it seems like the ultimate way to also integrate thermal management.
Integrated drivers on a DTP mcpcb would be the simplest option by far as there is minimal wiring to do, just screw the board down and wire in power (and modes if they can make it). There would be no external driver box as there is with my current testing rig. Like you said, the Thermal management will be ideal. The drivers will be happy and reliable being on a DTP board.
Oh sorry, I meant complexity in terms of designing the driver circuit. I have no idea in terms of what’s involved with that. Would you need to farm the design out?
I have a rep from a company that I am corresponding with about a possible mcpcb board design for my light bar.
However you go about it, it would be super awesome if you were to design it with end user LED upgradability in mind… thats a major limiting factor, if your board places too many components too close to the LEDs, or the LEDs arent on a separate star, upgrading for future LED improvements becomes difficult.
Looking forward to more updates (and saving my pennies)!
You have given me a different way to look at this project _Galt. Thanks. 