Wiring LEDS

[rcher]

I'm putting LEDS in and around my Delta type submarine. How do you guys plug the wires into the WTC?

[tupolev]

Hi,

I have the same question

Hi,

I have the same question
I'm thinking to put navigation light on my Alfa.

Can anyone help us, please ?


Regards.
Tupolev

[boatbuilder1]

hey guys no problems heres

hey guys no problems heres what I did on my nautilus
I have a BEVR dipped in liquid electrical tape two coats and dry for 24 hours and it is mounted in the wet portion of the hull, and this feeds power to the led's
the BEVR is fed from two ring connectors that screw in the the wtc from the outside right at the same point where power runs in to the wtc for the the radio
for the leds themselves make sure they are press fit not glued in as you want to replace them when they burn out after 10,000 hours or so ha ha
make sure you drop the voltage down to at least 3 volts for these with a drop down resistor 100k to 200k will work fine IMO and for safety sake insulateone leed of the led neg or pos doesn't mater use heat shrink tubing

hope this helps and if I have made a blunder then ramius the elctrical wizard should step in here he he
any ways this has worked for me in every application I have done

ca

[ramius-ii]

Hi Guys]http://www.subcommittee.com/forum/icon_smile.gif
Close, very close and

Hi Guys]http://www.subcommittee.com/forum/icon_smile.gif[/img]
Close, very close and I think you may have slipped a decimal point? LED’s have two specifications one is called Vf (Voltage forward) the other is If (Current forward). An LED with a spec of Vf = 2.1 volts and If of 30 ma. Would translate as follows: given a 6 volt supply we need to loose 3.9 volts so we don’t receive a single “pop” and then no light. We still need the current and as a simple rule of thumb, we reduce the current by 1/3 to allow for over voltages or other unforeseen oopses. So, now we have the two values we need. 3.9 volts (to loose) and we need 20 ma. to produce our light. Ohms law says R= E/I. Translation: the resistor value is the voltage divided by the current (in Amps) 20 ma is the same as .02 amps. So what we have (aside from an Excedrin headache) is 3.9 divided by .02 or a 195-ohm resistor, which they don’t make. Next value would be a 200-ohm resistor.

WTC to flooded area connections: The technique I like is to take the wires, twist them using a drill, and then pass them through a piece of brass tubing just larger than the wires, and extending 1/4 inch on both sides of the WTC. Once this done, add some RTV or T-88 to the wires as they are being pulled through the tubing. Stand the project upright and tape the lower end (the tape will be removed later) and as the T-88 settles, add to the top to completely fill the tubing. One trick is to use a heat gun to warm the tubing as this will cause the T-88 to become almost a watery consistency and bubble will rise to the top! Hope all this is of some value and if nothing else, when you have trouble sleeping, you can re-read this!

Best to all, Ed

[bradv]

Try this]Using LEDs

For more useful

Try this]Using LEDs[/url]

For more useful electronics explanations, check out the rest of the articles on "Electronics for Beginners" and "Intermediate Electronics"

And for even more complex articles, many of which are suitable for subs, check out]WebEE Tutorials[/url]

Yup, I'm an electrical engineer, so find the aforementioned sites invaluable resources

[rcher]

Thanks, Boatbuilder. My head is

Thanks, Boatbuilder. My head is still ringing from when I asked my girlfriend, " What's a BEVR"?

I want to to semi-permanently mount LEDS in the wet hull of my Delta but still be able to remove the WTC. So what I need is a connector. The "ring connectors" sound like what I need. Are they sufficiently waterproof? Are ring connectors like BNC connectors??

Next question, I'm using between 9 to 11 Bright White LEDS throughout the ship. For you EEs, they are 5500mcd rated 3.2v @ 150 ma. Do I wire them in parrallel or series? Can I use just one dropping resistor or does each LED need it's own dropping resistor.

Oh yeah, I'll probably be using a single 7.2 3000 mah nihm battery.

[dietzer]

Next question, I'm using between

Next question, I'm using between 9 to 11 Bright White LEDS throughout the ship. For you EEs, they are 5500mcd rated 3.2v @ 150 ma. Do I wire them in parrallel or series? Can I use just one dropping resistor or does each LED need it's own dropping resistor.

Oh yeah, I'll probably be using a single 7.2 3000 mah nihm battery.

You must wire them in parallel. Wiring them in series won't work. And I highly recommend using seperate resisters, especially since each LED sinks 150mA of current. If you have 10 of these LEDs on at the same time they sink 1.5A!

You're going to need that 3000mah battery...

Hope this helps,

Carl

[Guest]

Hi,

Go here for a superb

Hi,

Go here for a superb tutorial on wiring LED's

http://www.lsdiodes.com/tutorial/

Also there are some free links to LED calculators on that site, which make calculating resistor sizes a cinch.

They also sell LED's at VERY competitive prices, and they offer a blinding service.

Andy

[rcher]

My LEDs are ebay specials

My LEDs are ebay specials and right now you can get 50 bright white LEDS for about $4 plus shipping.

Dietzer, I'm not sure that I have the "150 ma" rating right. I checked some other places and it looks like these LEDS are rated at 20 ma. Hmmmmm

[ramius-ii]

Hi Rcher]http://www.subcommittee.com/forum/icon_smile.gif
Based upon

Hi Rcher]http://www.subcommittee.com/forum/icon_smile.gif[/img]
Based upon what's know and unknown, IMO, I would put my LED's in groups of 3. That being, 3 LED's in series. Then each group of 3 in parallel with the other groups. The result would be not having to use a resistor. Try one group first, just to make sure you get the desired results. I think you are correct about the current, a 2300 mcd LED draws about 20 ma, so at 5500 mcd, 40-50 ma would be expected. Note that "super-bright â„¢" LED's are usually several single LED junctions on one substrate. So if the manufacturer is using 8 junctions in parallel, then 150 ma would make sense. Best to just do a little measuring with a meter to be 100% sure.

Best, Ed

[PaulC]

Go here for a superb

[color=#000000]

Go here for a superb tutorial on wiring LED's

http://www.lsdiodes.com/tutorial/

Now that is a helpful link! Thanks, Andy.

No offense to the other links/info mentioned, that one just really connected with my learning style. ]

[rcher]

Yep, those links were great!!

Yep, those links were great!! BUt I still need to figure a way to plug the leds when I take the WTC out.

I just had a brain thing, how about using the sealed weather proof plugs from GM cars? I know they are on carded stock at the local AutoZone.

[JWLaRue]

If you really need to

If you really need to run your LED wiring into the WTC (I don't, I run them directly from the main battery), then this may work for you]http://www.subcommittee.com/forum/icon_smile.gif[/img]

-Jeff

[ramius-ii]

Hi Rcher]

[color=#000000]Hi Rcher]

[dietzer]

Next question, I'm using between

Next question, I'm using between 9 to 11 Bright White LEDS throughout the ship. For you EEs, they are 5500mcd rated 3.2v @ 150 ma. Do I wire them in parrallel or series? Can I use just one dropping resistor or does each LED need it's own dropping resistor.

Oh yeah, I'll probably be using a single 7.2 3000 mah nihm battery.

You must wire them in parallel. Wiring them in series won't work. And I highly recommend using seperate resisters, especially since each LED sinks 150mA of current. If you have 10 of these LEDs on at the same time they sink 1.5A!

You're going to need that 3000mah battery...

Hope this helps,

Carl

I forgot to mention that when I said wire them in parallel, I was assuming you would use a 5V BEC circuit. Since each LED needed 3.2V, you could only have 1 in series with a resistor operating from a 5V supply. That's why I said wiring in series wouldn't work. The resistor is needed to drop the voltage from 5V down to 3.2V for the LED.

But if you are wiring the LEDs straight off the 7.2V 3000mAH battery, then you could put two in series but you still need a resister to drop from 7.2V down to 6.4V for the two series LEDs. You could then make 5 parallel circuits of 2 LEDs each to get your 10 LED total.

Carl