Basement Shelves Upgrades
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Feb 2014: LED strips have been added to the underside of each shelf by Gatohaus (talk). These are SMD 5050 strips, 5m long, 300 LEDs each that draw 1.2A per meter at 12v. Note they have been trimmed nearly a foot each to fit. Total maximum wattage for the 10 strips currently in place is 10 x 72w = 720w. Output is around 800-900 lumens per meter. (~40k lumens) A good balance between light and heat (longevity) seems to be in the 3 to 4A per strip range.
The location of the strips was chosen: to be somewhat protected, to light the shelf adequately, to avoid as much glare as possible, and to provide significant spillage into the surrounding area.
Feb 2014: Expect a few of the strips to fall down. Some are still partially attached by their adhesive tape which won't really fail until they're warm for a while. When they do fail, reattach them with a hot glue gun. That seems (fingers crossed) to be permanent.
SMD 3528's were also tested (the strip remains in use on the shelves). The 5050's were the same price (~$12) at about the same efficiency but allow for a higher maximum brightness (and greater power draw of course).
Adhering the strips
The tape adhesive that comes on the strips works very poorly on OSB (shelving material used). They'll hold while the lights are off, but once they warm up the adhesive begins to fail. I tried 3M's "77" spray.. an embarrassing failure. It too loses adhesion when warmed.
Trying mechanical attachments, typically a nail or staple with a plastic brace, the type used to hold cables in place, proved troublesome. The OSB is hard enough that significant force is required with a hammer to drive the nails in. Over a span of 50m of LEDs it seems likely that misses would occur probably smashing some of the LED components.
In the end a simple hot glue gun seems to have worked.
Wiring & Power
In hindsight it would have been better to mount the strips with more of the connecting leads sticking out at the end. The leads can easily be replaced if needed, they're just surface mounted.
I used a PC's ATX power supply which has 2 x 12v at 15A. (I managed to damage this ps somehow.) I don't know how efficient it is but after spending several hours hunting for options in our collection of stuff, this seemed the best choice. Perhaps it can be replaced at some point. I'm giving one of the 15A sources to the lower 3 shelves, and the other to the top two shelves. This means the upper ones will be brighter, but the spill over will help illuminate the surrounding area.
Temporarily (which tends to become permanent) there is another ATX ps plus a couple of in-line wall warts in place of the ATX mentioned above. This ATX has 12v at 21A and the two wall warts have 5A and 2.5A at 12v. Not quite the distribution I'd like, but it works.
Well... almost works... After being on for half an hour or so the 21A ATX takes a nap. Exhaust air feels cool, but it's probably too much of a load. So I added another computer power supply (~5A) to help out. Seems to be stable. Need help either repairing the original ATX supply or finding something else.
Things to Improve
In general I'm not exactly proud of the wiring. It's solid and safe, but not quite pretty. If someone wishes to redo this work, please do!