-----Original Message-----
From: Cliff Redus <cliffordredus@sbcglobal.net>
To: personal_submersibles <personal_submersibles@psubs.org>
Sent: Mon, Jan 16, 2012 2:55 pm
Subject: RE: [PSUBS-
MAILIST]
SeaBlaze3 LED bench test
Psub postings have been a bit slow so I have decided to post
a short test I did today on an off the shelf LED light. Subsea lights are very expensive for psub
applications so I was looking to see what kind of depth performance I could get
with an off-the-shelf LED marine light for pleasure boats. I chose to test the Lumitec SeaBlaze3. See the YouTube clip of the test at http://youtu.be/WXYPjIgoxLE . Prior to the test, I took it to swimming pool
to see how it worked at night. The light worked great and very bright. You could see across a an Olympic sized swimming
pool without any problem with just one of these lights. The application I am contemplating would use
seven of these lights working off 24 VDC.
The lights will work on 10-30 VDC.
For 24 VDC, they pull 1.1 amps. To conduct the test, I built a pressure
chamber out of 4 inch, schedule 40 galvanized pipe fittings. I then made up a
simple electrical penetrator using a ¾ inch pipe fitting, nails and some two-part
epoxy. To pressurize the test chamber, I
used my pressure washer with a bypass valve.
To determine when the unit failed, I connected the light through the DC
current section of my multimeter. Because
the line pressure for my house during the test was 74 psig, this is the minimum
pressure point for the test.
Results were that the LED light worked fine for about 4
minutes at 74 psig or 167 fsw. At that
point, the case flooded. The application
I am looking at has a 500 fsw design depth with a max test depth of 625
fsw. Therefore out of the box these
would not work but it would be straight forward to pull the electronics and LEDS and insert them in a custom 1-atm shell. This lights was $220.
The reason I thought this had a chance of handling the pressure was because the case is anodized aluminum and the lens is glass. The LED face plate was in contact with the lens so structurally it was being supported. My guess is that they must have used some kind of adhesive to seal the lens rather than an o-ring. My next step is to tear the fixture apart and see if the electronics and LED could be repackaged for pressure.
Cliff