Any interest in a 5x P7-Based Worklight? New Pictures !

[Sabrewolf]

Re: Any interest in a 5x P7-Based Worklight?

Hey Sabrewolf:

I've converted several work lights to LED. Pictured below is an early version with a mishmash of Q5s and P7s.

Heat is going to be a real concern in your design. Make sure you have a way of getting it out of the light body. Avoiding thermal runaway is A LOT harder than it looks. Then again I'm running more lights and have linear regulators onboard adding to the heat load.

Good luck!

OOOOOHHHHHH Boy

And i thought "MY" Name was CAPTAIN OVERFRIGGINKILL!
Good Work ! Thanks for the Advice :wave:

 

[DM51]

Re: Any interest in a 5x P7-Based Worklight?

If you want more inspiration, take a look at the Data Bank 70.

 

[Sabrewolf]

Re: Any interest in a 5x P7-Based Worklight?

If you want more inspiration, take a look at the Data Bank 70.

I won't go to that extreme :devil:
But Yes, It is a good inspiration

 

[Sabrewolf]

Wooohooo! Progress Pics are up!

 

[jeffosborne]

I like thinking outside the box, and this qualifies. You mention using 17 volts at 3 amp, that's 51 watts. Your heatsink is nice and large, but I wonder what kind of temperature rise you will get. The LED might be spec'd up to 250 degrees F, however. We are eager to see the results! An beam shots, of course. Jeff O.

 

[LED Boatguy]

Test, test, test

I like thinking outside the box, and this qualifies. You mention using 17 volts at 3 amp, that's 51 watts. Your heatsink is nice and large, but I wonder what kind of temperature rise you will get. The LED might be spec'd up to 250 degrees F, however. We are eager to see the results! An beam shots, of course. Jeff O.

ASSuming you have good thermal contact between the copper (that is copper, right?) base and the heatsink, at 51 watts my guess is it'll work just fine outside in 60 deg F and breezy conditions. It'll likely roast itself in warm weather and no air moving by the heatsink's fins other than natural convection. It'll need a fan on the heatsink, and even then it'll likely only work if you've spent a good deal of time assuring flat, metal-to-metal contact between the copper bar and the heatsink. I'd also widen the copper bar by an inch--ASSuming the back of that fixture is flat. I did one of those fixtures early on and had put it in a mill to get the back flat.

Suggest you put a thermocouple on the copper bar and see what happens under different conditions.

You can also use drivers that reduce their current as they heat up. It won't work with the P7's current, but the Zetex ZXLD1362 driver (and I'm sure others) have an ADJ pin that can be driven by a thermistor.

$.02