Posted by Franz [24.149.37.138] on Tuesday, December 15, 2015 at 14:02:03 :
In Reply to: Re: O.T. led spot light bulbs for wet locations? posted by Sherman in Idaho [50.120.91.47] on Tuesday, December 15, 2015 at 11:33:53 :
OK, first, odd as it seems, your housing is acting like a thermolytic vacuum hospitals employ to operate patient suctions, and nobody yet born will stop it from sucking water in regardless of what is done to seal it. Light on- heats & expands air in housing, light off, air cools and vacuum is created.
Regardless what the label says, ALL rubber and plastic cords are water permeable, and the seal on the housing is permeable as well. The only way you beat this effect is either venting or pressurizing which is why hanging phone cables and underground electric cables are pressurized. You can minimize it at 10 feet of depth by venting the housing with a small tube and sealing the housing up with the Miracle Product GOOP.
The GE sealant sales people will deny GOOP is better, they lie.
Start/stop cycles are more filament erosive than constant burn in tungsten lights, that is probably what is giving you short life combined with the water shattering the envelope. The 2 ideal solutions are a slow power up (like stage lighting) or remote lamp fiber carried lighting. Neither is probably in your budget, but fiber would be a ball to play with in that application as weighted bundles could be dropped to different depths. That's similar to the current lighting in use on the Empire State Building and may actually be doable for you given what's available on ePay and "shorts" laying around. You might get free samples from Corning Glass to try out.
The Cheap&Dirty immediate solution that comes to my mind is the current generation of 12v DC LED spotlights coming into use on police and fire equipment. Light output to current consumption is phenominal, and the illuminator is sealed beam.
You can probably make the 12v supply from a garden lighting transformer and bridge rectifier which can live above the water level. Even a battery charger that no longer charges 12 volt batterys would work, and those can generally be had free.
Unfortunately my map says the job is in Willy's service jurisdiction so I can't come and play even though I do have MSHA paper that says I'm a Mine Electrician. Get Willy over there and start playing with the cheap LED tape and rope light available from both ePay and GearBest.
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