LEDs for Dummies

Doesn't look very "dumb" to me! You've got it figured out.

I get it now! Thank you for posting.

Concise and very helpful.  A great reference.  Thanks, TMack.

Do those pass an absolute set voltage or does it vary with the input voltage?

 

That is a very good way to solve the problem.

You have to have more in than what goes out. I just dialed it down to 11.5 volts for my 12 vdc LEDs.

I bought the AC/DC to DC converters the first time around, I just picked up the DC to DC boards.  I think I like the AC boards better even if they cost a little more per board.  I am using two of the AC converters on my Layout now. 

I picked up the DC boards for future, but I ended up using one for lighting a cabinet. I have 13vdc in and can only get it to adjust to 10.69 vdc out and no other increment.  It is lighting a 6 foot strip.

 

-Ted

 

If you are willing to buy more than a few of those ac/dc boards the sellers on eBay will often take less. I bought 20 for $100 about a year ago. Great product with a ton of possible applications.

A picture is worth a 1,000 words, thanks for putting that together, I saved it! 

 

I have some of the AC/DC converters, they are nice. I think I got them from the same place as your link. I ordered 8 or 10 and had 1 bad one. Emailed them and they just sent me another one for free no questions asked, didn't even want the bad one back. Pretty good service.

 

I have recently seen some on ebay with a digital readout on the output voltage, for a little more in cost. Thought that was a neat feature, may have to try a couple of those. 

Very helpful to me also . I appreciate the picture it certainly does say a 1000 words to me anyway.

What is the problem the step downs solve? thanks. 

 

For one thing, you could use up your left over 9-12vdc wall warts to power your Miller signs at 4.5 vdc or any other items needing less voltage. (DC to DC converter)

 

The AC/DC converters may be a bit more useful, then you could use either a DC wall wart or AC track power or AC accessory power for your input to power the above items.

 

Both have adjustable outputs so you can set them to any voltage you want as long as it is less than the input voltage by whatever the specs are for the device.

I know this is not the exact issue being discussed but it is related. When replacing bulbs with LEDs, the type that look like postwar light bulbs, do you have to add a resistor to the circuit?

Thank you and all the best,

Miketg

Depends on where you are putting the light and of you buy LEDs with a resistor already installed.   If you are looking to change the lighting on your engines or rolling stock then the converters here are of no use.  There are a couple discussions already on how to add a bridge rectifier to accomplish that.  This post is more about power and LED lighting for the scenery and layout

Not sure this applies to your question, but there are replacement bulbs that are LED, you just take out the old and put in the new, if applicable. Nothing else required.

 

I have purchased them here with good results

 

TrainAidsA

 

There are many other places to purchase these as well, this is just one I have used.

Amazing what you can find on this forum, this just answered all my questions on led lighting and building lighting.  Thanks TMack.

 

Pelleusmc

Mike

TMack,

thanks for posting this great info!

I need to convert a few K-Line passenger cars that have burnt out streamlighting. Which components would you suggest to use?

thank you!

Here's how I do it.  The only change I'd do from this is to make the capacitor a larger value for more flicker resistance.  A 220uf will keep the lights nice and solid, even on dirty track.  Most of the work is taking the car apart, the actual LED conversion is a piece of cake.

 

After the picture was taken, hot glue was used to secure the components.

 

 

Thanks John

where can I buy the LEDS and other parts, thanks again!!

 

I buy the LED's on eBay or Amazon, I shop for the best price for a 5 meter roll of 300 LED's.  I normally use Warm White for the task.  The other parts I get at Digikey or Mouser, my two favorite electrical component places.

Gerry, I have not lit passenger cars yet.  What I posted was more for buildings and scenery.  I think Jackson is taking those DC to DC boards and putting those in his passenger cars.  I doubt the DC to DC boards are gong to work conventionally with variable track power and for that matter I doubt there is a simple way i.e. Dummies version, to wire up passenger car LEDs for variable/conventional running.  

 

There are some really nice folks here willing to help, but they really don't get that their explanations on most this stuff is so nerded out, that many of us give up.

John is this choke ok?

http://www.ebay.com/itm/22uH-A...;hash=item43b6723442

To clarify a bit.

i light all my buildings with DC from a transformer thru a large full wave bridge rectifier on a circuit totally separate from track power. i then light all my buildings using LEDs fed from individual DC to DC step down regulators. This permits me to vary the amount of light in each building.

 

 As to passenger cars -- as i run TMCC exclusively with a constant 18 volts AC for track (and therefore passenger lighting) power my little rectifiers (AC to DC) combined with those inexpensive regulators (DC to DC) work well in passenger cars and cabooses. As a point of reference i find that 6 to 9 volts is more than adequate for lighting cars with LEDs. Hence i can see no problem running the same set up with variable track power in a conventional environment. Most of the E units require about 6 volts to engage. Assuming you run conventional trains at 6 volts or higher my rectifier/regulator combination will work fine. Car lighting just will not come on below 6 volts. But with the regulator adjusted to 6 volts DC output any AC input from 6 to 21 volts will still result in a constant 6 volt DC output to the LEDs.

 

jackson

 

 http://www.youtube.com/watch?v...&feature=channel

Gerry

this Ebay - line is straight information from John, in a past LED , discussion,

As soon as I saw his information I ordered, 

You CAN light up Madison passenger cars with these

what a difference, !!!!!!!!!!!

http://www.ebay.com/itm/10-x-LED-5mm-PRE-WIRED-LEDS-9-VOLT-WHITE-9V-PREWIRED-USA-/390668223376?pt=LH_DefaultDomain_0&hash=item5af5a40390#ht_1182wt_903

 

Johns an electrical wiz, like Dale.....when it comes to that kind of electrical I'm a certified dummy sevant, but his circuit is an easy one with only 5 things including the LED strip. It will work fine with DCS, and at either full voltage{DCS/TMCC} or for varied conventional. You can loose the choke if you'll never run DCS or TMCC.

I've got everything I need now to convert all my MTH cars to LED...and my 5 buildings....I just have to sit down and do them up sometime soon.

Yep, and I just ordered 50 of them, very good price!

 

Thanks to everyone for their input. I just ordered the choke off ebay. Anymore links to parts needed for passenger car LED upgrades would be appreciated. For the newbies the electrical specs are tough to navigate...so much easier if someone just says "buy this". Any others that can be gotten off ebay? Will any warm white 5 meter roll work or is there a certain voltage needed? Thanks again!!

ok here was the follow up i just purchased for the 1n4003  http://www.ebay.com/itm/1N4003...;hash=item5d220a7524

Virtually all the 5 meter LED strips are made for 12 volts.  I use the ones that have 300 LED's, there are also rolls with 600 and 150, but I find the 300 is the right amount for most cars.

 

My designs simply limit the current, as that renders the voltage question moot.

 

You can get the other components, with the possible exception of the CL-2, on eBay.  I just picked up some 1N4001 diodes for 4 cents each, hard to beat that price.

 

Here are the remaining parts, the chokes above are the last item.  All you need are the LED reel and you're set.

 

eBay 1N4001 Diodes

 

ebay 220uf 35v Capacitor

 

Supertex CL2N3-G at Mouser

just bought the 1N4003!  thanks!

have everything on order, thanks for the links. I'm sure there will be questions when the parts arrive, thanks to all!

Jon I have a bunch of 100uf 35v capacitors.  should I run them 2 in series?

I also picked these up when I started planning this project. I think they are thermal links in case you short the pickups / wheels?  I believe they went inline after the pickup roller.

 

I believe they were part of Dale's original plan.  comments?

 

Thanks Bob

You put capacitors in parallel to increase the capacitance.  The picture is indeed a PTC, that goes between the rollers in case of a derailment.  It protects the wiring between the rollers of one roller sits on an outside rail.

 

Thanks for sharing

Please understand that having grown up in the 1990's there were no school based electronics, woodworking, machining, or automotive classes offered in either middle or high school where lived, so I need things explained in very simple terms when it comes to projects like this -- understanding what to buy and ideally what each part does would be super.

 

On the passenger car circuit as John outlines, is the function of the CL2N3-G?

Is this a resistor of some type of does it do more?

 

I get that the coke holds back the DCS signal to prevent issues there, that the cap takes and holds a charge to keep the lights on, but the other two parts the CL2N3-G and the 1n4001/1n4003 diodes role or function remain a mystery. I've also seen discussion about needing to convert the AC track power to DC, does one of these do that or is there a missing component?

 

Thanks to everyone for helping clear all this up, I have a good sized fleet of passenger cars and several rolls of LED awaiting additional parts and my understanding to wire in.

 

Best,

Jason

  

The CL2 is a constant current device.  It's a two-pin IC that limits the total current output to 20ma.  It connects into the circuit just like a resistor.  This current provides about the right amount of lighting to most passenger cars, perhaps even a bit bright.  If I want to dim them a little, I just connect a properly sized resistor across the output and shunt some of the current away from the LED string.  I will say that you shouldn't need more light than the LED strip provides at 20ma unless you like sunlight in the cars.

 

The function of the diode in the circuit is simply to convert track AC to DC.

I've tried these and they're awesome for cars and buildings.

 

http://www.modeltrainsoftware....rains-buildings.html

 

George (G3)

I've tried these and they're awesome for cars and buildings.

 

http://www.modeltrainsoftware....rains-buildings.html

 

George 

 

These are nice however certain model diesel locos such asn MTh gp38's, two of the Leds will NOT reach to the end of the long hood [lighting up number boards with this circuit] because the wires are too short. I contacted model train software and they claim most of their customers have no issues.

Thank you very much for the so clear even this electronics baboon more or less understand the parts, what the do, and how to put them together for LED lighting of passenger cars.

 

All parts have been ordered, in bulk, within the next ten days the first install shall begin and I hope with your continued support that will be the first of many successful LED upgrades.

 

I truly do appreciate you each taking your time to dumb this down and to giving enough positive encouragement to get me (and I hope others) off our backsides and on to making this project successfully happen.

 

Best,

Jason