starfury lighting help....

Antenociti · Post by **Antenociti** » Sun Nov 18, 2012 11:15 am

looking for a bit of help verifying my lighting for a starfury..

going to be running it of a ac/dc adapter putting out 9v/600mA

8x 5mm blue superbrights... (2 per "engine"

Blue 30mA 3.65Vf (typ) 4.2(Vf max) 5Vr

then 2 x red ultrabrights for the cockpit

Superbright red 30mA 1.85Vf (typ) 2.5(Vf max) 5

What is the best way to hook these up?

put them all into a series of 2 LEDs.... 2blues x4 and 2reds?

or put them all in individual in parallel with a resistor on every LED?

Mr. Engineer · Post by **Mr. Engineer** » Sun Nov 18, 2012 11:37 am

Assuming the following specs:

Blue: 3.65v, 20mA
Red : 1/85v, 20mA

And with your 9v power supply, the resistor value for each type of LEDs are:

Blue: 270 Ohms, 1/4 watt
Red : 390 Ohms, 1/4 watt

You can get more assistance from this Popular resistor calculator website which also helps you in wiring up your LEDs: http://led.linear1.org/led.wiz

But personally, I prefer 6v and also, I would like to wire each LED in parallel, complete with its own resistors. But that's just me.

Antenociti · Post by **Antenociti** » Sun Nov 18, 2012 11:51 am

Its a switchable power supply so it can do 6v, what is the advantage?

I also dont mind wiring each in parallel with their own resistors if there a perceived benefit?

The reason that i'm doing this is that after a 5-year hiatus in a dustry draw i pulled out the model and found that the LEDs were "failing" sequentially... which was rather suggestive of my mucking up the wiring/resistors at some point years ago.

SO i want to get it right this time. :-0

Glorfindel · Post by **Glorfindel** » Sun Nov 18, 2012 4:21 pm

I believe the benefit is that if you wire them up in series if one burns out the whole thing goes out. In parallel if they all go out then your eyes are closed.

starsend · Post by **starsend** » Tue Nov 20, 2012 5:30 pm

Correct, if one LED ever burns out you will only lose that one if in parallel. If in series, you will lose the whole "string".

Madman Lighting · Post by **Madman Lighting** » Tue Nov 20, 2012 9:06 pm

Sounds like you're doing it right. 6V DC, one resistor per LED so that any failures only take out one LED. That will give best current regulation to the LEDs.

One thing you should be doing is using LESS than 20mA for your LEDs to improve reliability. I use 18mA for all my stuff. The difference in brightness is hardly noticeable but it improves reliability because now you're 10% below the full rated current.

Of course, you could always just get one of these and be done: http://home.comcast.net/~johndavidcook/starfury.html