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Power led ...loss power with high temperature

Power led ...loss power with high temperature

(OP)
Hi folks

Do you know the reason why the led driver loss a bit of power when it become hot?

Tks

RE: Power led ...loss power with high temperature

Do you mean why a good LED driver will automatically dim when they get hotter? It's to preserve the life of the LED.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Power led ...loss power with high temperature

Otherwise it's a flash bulb.

RE: Power led ...loss power with high temperature

To confirm this blow a bunch of air across it once you've decided 'its lost a bit of power' and see if it gets the power back.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Power led ...loss power with high temperature

(OP)
This is the point if i blow air around the led driver the power return high, so where i can find a value to recognize this behaviur
The air temperature around the driver is almost 78 c
The temperature TC on the led is 72 c

When the driver's temperature get down to 65 c the power get high

....Sorry for my english and thanks to all

Regards
David

RE: Power led ...loss power with high temperature

78C around the driver is way toO high!! You need to correct the ventilation around it by mounting it vertically so fresh air can convect past it, or open the space up so the hot air can leave with cool air replacing it, or add a fan to force fresh air past it. You should also try to get the air moving past the LEDs to extend their lives too.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Power led ...loss power with high temperature

(OP)
Yes i get your advice but i was wondering is there a diagram that show the correlation between the driver temperature and his power factor?

RE: Power led ...loss power with high temperature

There is no standard for that, it's strictly a part of the specific driver's design. There is likely a fold-back curve in the driver's data sheet. Do keep in mind for every 10 degrees hotter the unit runs its life is cut by one half so trying to run the things just barely below the 'dimming temperature' is going to continue squandering the driver's and the LED's operating lifetimes. Where they might run fine for 10 years, you're only going to get maybe a year out of the system.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Power led ...loss power with high temperature

(OP)
Yes thanks, everyting is clear now
Have a good day

Regards

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