Finally Found A 48-SMD 12-Volt Panel
Yeah Yeah Yeah My aged eyesight ain't so hot. I need bright light. Until I tried this plate I might as well have been using a night light to see by. Since I am a law ignoring tax evading shopper th...
Forum Discussion
MEXICOWANDERER wrote:
Something's up...
My 10-watt heatsinks are 90 mm in diameter with 25 fins. Driving the 10-watt chip -exactly- at 10-watts (9.88 vdc) with convection alone I am getting a Delta T temp of 34 degrees F using pure convection cooling. One such of my devices has been 24/7/365 since June 2013 so in reality the device cannot be being overdriven.
Those plates in that image have perhaps 10% of the thermal radiation area of my original equipment grade heatsinks that cost $22.00 in China. They are correct because they are drilled and threaded for the 10-watt commercial chip.
No question in my mind that aluminum plate would help IF IF IF IF sufficient area were allowed ABOVE the plate to permit convection. If that plate was mounted flat against an insulation it would prove to be pathetically ineffective.
Wonder what chip they are using i.e. total wattage rendered? Most flat plates afford 2.5 watts consumed, and my plate was measured last night at 3.1 watts which is really pushing thermal limits.
Bonding directly to aluminum is not going to make this device inexpensive.
Gotta watch for honorable slight-of-hand. A "new" 12-volt "50 watt" floodlight on eBay consists of (5) severely-under-driven 10-watt chips. Zank yu very much but I'll stick with a single chip, properly driven attached to a proper heat sink.
I tabbed a site that sells quarter-inch LEXAN polycarbonate which can be fashioned and cemented into an effective lens. Using a black anodized heat sink and sealing-in the chip results in bullet-proof durability. The wire pass through hole in the finned heat sink will be sealed with JB Weld.
You are repeating what the flashlight and nighttime headlamp wearing mountain biking crowd discovered 5-6 years ago. Under drive it and save heat, or drive it properly, 1000mah, and heat sink it properly. Most of the EE's I knew that tinkered with these LEDs, came to the conclusion that 700 to 1000 Milliamphours was the sweet spot for driving a 220 to 375 lumen out put single 3.7V LED chip.
