I don't think the power is the issue since you have it available.  The real issue is how to physically mount the LEDs.  How many do you think you need?  If you have a convenient place to mount the self-adhesive LED strips, they're an attractive option to provide uniform lighting over a fairly wide space.  The LED strips are designed to be split into groups of three and the require 12 volts DC to drive them.  You can use lower voltages (down to about 8 volts) for lower intensity lighting.  I normally use a constant current circuit for a task like this, that way I can control the light intensity easily.

The roof overhang covering the platform is a little over 13".  I was thinking to either have 2 rows (front & bacck) or just 1 row going across the center of the overhang and leave at least 2 to 3 inches at each end not lighted.  To mount I was going to try to find the LED's with the self-adhesive backing and attach directly to the underside of the overhang.  Then will have to find someway to conceal the wiring going down to through the platform to the power supply.  I think covering the wires will not be an issue due to an earlier thread I posted and from that got some good ideas on how to conceal these wires.

You state that every set of 3 is wired together, would that still apply if I used a string of say 9 together without a break?

Yes, they work in groups of three, but you can light the whole 5 meter roll from one end if you just connect 12 volts to the first group.  I normally do that right after purchase to make sure they all light.  How does $8.48 for 300 strike you?

5 Meter Reel Warm White 3100K Flexible LED Ribbon 300 LEDs 16ft 2026ww-31k

Heh, wow...they're even cheaper than when I bought a roll back in March (according to Amazon)

---PCJ

The price is definitely right, thanks!

Are the wires on these reels very fine?  What gauge or type wire do you suggest using to make the power connection? 

You can use any gauge wire you feel comfortable with.  For wiring passenger cars, I use #32 wirewrap wire, it's easy to hide.

I love the strips, I'm putting under counter lighting in with them, and I'm using them in quantity in all my passenger cars.  They're dirt cheap and very convenient to use.

Hi John.

What is the approximate length for a unit of three, six and nine LED strips?

I just measured one of my reels, each three LED group is 2" long.  Obviously, that makes a six LED group 4" long and a nine LED group 6" long.   I've seen some that had wider spacing, but the ones I references previously in this thread should have the same 2" spacing.

John,

I know there have been lots of threads about the LED strips but I dob't remeber if the strips are rectified so they work with 12 volts AC or do they work on 12 Volts DC?

Joe

12V DC is the required power source.  You can reduce the voltage a bit to lower brightness, at around 8V they don't light at all. 

Each 3 LED group uses a maximum of 20ma power at 12V.

LEDs of in themselves are DC devices.  All the strips I have seen operate from an external DC supply.  Therefore you will need a diode or diode bridge (and capacitor) to change the track AC to DC for the strips.  If running DCS with 18VAC then the rectified DC will be way higher than the 12V the strips require.  Dale and others have posted how to reduce this high DC down to 12V or lower to create the proper light ambiance within the car.  After all, you don't want your passengers wearing sunglasses because the overhead lighting is a blindingly bright as sunlight!

John,

Thank you for the quick response.  As I stated I know there are a lot of threads about the use of these LED's but I just didn't remember if they ghad a built in rectifier or you needed to power with a DC supply such as a walwart or an HO power pack.  Hopefully I'll be able to remember this the next time a threadf about these rolls of LEDs comes up.

Joe

I run LED strips for my under-the-cabinet lighting in my kitchen at 12V, and it is plenty bright for working on the counter with no additional lighting.  I have found that running several LED triplets off a single 20 mA source (a CL-2 current regulator) give an appropriate level for train applications.  Experiment for yourself and decide.

(BTW, I recently developed an incremental lighting system for my kitchen.  The first push UP on the momentary switch gives me the 10 feet of LEDs under the top cabinets - less than 5 watts.  A second push turns on one pair of 30" fluorescents (about 60 watts) in the ceiling, and a third push brings on the second pair of fluorescents.  One downward push turns everything off.  I have duplicate linked controls at the two entrances to the kitchen.  I love it!)