[C320-list] LED field test

[John Frost]

There are many design elements that can shorten an LED's inherent longevity.
I understand that one of the most prevalent is overdriving the LED with too
much current. This makes the bulb much brighter, but greatly reduces its
life. Sort of like putting 18 volts into your 12 volt halogen light bulb.
Good designs lower the current for longer life. That is one problem in
consumers trying to pick a light based on a short test.

Happy Sailing!

John
2007 C320MKII
Hull 1118
Guntersville, AL

-----Original Message-----
From: c320-list-bounces at lists.catalina320.com
[mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of warren updike
Sent: Thursday, August 06, 2009 5:42 PM
To: C320-List at Catalina320.com
Subject: Re: [C320-list] LED field test

What I thought interesting about marinebeam.com was their "Constant Current"
chip that they claim will maintain the forward-current to the junction
regardless of voltage (within limits.)  That means that whether your
alternator is cranking out 14+V or battery only is yielding 12V, the LED
will remain at it designed voltage.

I experienced this after replacing the burned-out pilot light on my 15-year
old propane switch with a 12V LED bought from a local electronics store.  It
worked well for a year or so then quit.  My shore charger which I leave on
when the refer is running simply overran the LED over time (I surmise.)  

Read the link on the marinebeam.com site for "Constant Current."  If true,
I'm sold.  However, I'm no engineer so perhaps one of you slide rule types
can comment. (Slide rule??? Perhaps I'm dating myself.)

Warren & Pattie Updike
Catalina 320, #62, "Warr De Mar"
Middle River, Chesapeake Bay



-----Original Message-----
From: Jon Vez [mailto:jonvez at comcast.net] 
Sent: Wednesday, August 05, 2009 6:57 PM
To: C320-List at Catalina320.com
Subject: [C320-list] LED field test

Using Karl's invaluable research I bought several LED's before our summer
cruise and here is what I found:

I bought 2 MR-16's and 1 Luxeon spot light for the main cabin from
LEDWholesalers (non-marine). Although I was a bit skeptical with dealing
with the company, they delivered--right before our trip. They worked as
advertised. The light quality is excellent and they are inexpensive. I
believe I paid less than $60 for all three. However, they do produce
significant radio interference. 

I also bought a MR-11 for the aft cabin reading light from Marine Beam based
on Orlando's recommendations. This is an excellent light and the company is
great to deal with. However, this light alone was $24.

When looking on the Marine Beam website I came across an interesting PDF
explaining the pros/cons of different LED's--it's obviously meant as a
marketing tool as they warn against 'chinese made' LED's, etc. However there
is some valuable information describing why some lights are more expensive.
They warn of interference and I did find that the LED Wholesale lights do
produce significant interference--like forget about listening to the radio,
whereas the MB light produced no interference. Both sets of lights are
extremely efficient--.1 to .2 amp hours--and overall I'm happy with
them...just thought I'd pass my experience on for those looking to upgrade
your lighting....

Regards,

Jon Vez
Solstice #582

-----Original Message-----
From: c320-list-bounces at lists.catalina320.com
[mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Karl
Mielenhausen _/)
Sent: Wednesday, August 05, 2009 3:26 PM
To: C320IA Discussion List
Subject: [C320-list] Motion Sensing LEDs

Some of you have been asking about the LED array that several of us have  
bought (I use mine in the head compartment).
They are back on sale here...
http://www.meritline.com/led-auto-sensing-lamp-700---p-33224.aspx?source=dea
lnews

-- 
Karl Mielenhausen
Catalina 320 Hull 690
New Bern, NC