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Discussion Starter #1
I'm sure someone must have done this but I have not found it.

The new Aristo-Craft Doodlebugs and Heavyweights with LED's have convinced me that I can get enough light to make me happy if there are enough LED's (14 LED's with Aristo-Craft).

While I run primarily track power I do have a quantity of LGB Moguls that came with decoders and are pulling LGB 3080 series coaches. Since I prefer passenger trains I tend to put my newest and best locos (the ones that came with decoders) with them.

This has led to a problem of sorts.

When friends visit and I want to run MTS to give them control of trains I end up having to give them freight trains (to keep amps under the MTS 5 amp limit) but then I have to swap freight train Moguls with passenger train Moguls to get locos with decoders. PLEASE do not tell me to put decoders in everything - it just is not going to happen. Also I would not be interested in a booster. I already have one and it is used to power the middle track and another booster would be cost prohibitive for this project.

The obvious solution is to convert a consist or two of LGB Coaches (6 coaches per set) to LED's and thus probably cut the power needs in half.

Something like Aristo does with their Heavyweights seems perfect. Perhaps a strip that would hold 6 LED's per coach, attach to the existing threaded mounts for the LGB lights and to the LGB wiring harnesses from 68333 light sets.

Power for the lights is normally from the back of the LGB Mogul Tender but a complication is that I sometimes also get power from a Drover's Caboose at the end of the train.

One solution would be to move the ball bearing wheels (with electrical pickup) from the Drover's Caboose to the first passenger car which would keep the total number of track contacts for the loco but make it easier to wire all coach lights in parallel.

Has anyone done this or is there a company that offers such lighting strips?

I have never tried to do anything DIY involving LED's so I have no idea what I am looking at in terms of cost and where to find the best selection of products and prices etc.

Any suggestions?

Thanks,

Jerry
 

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Discussion Starter #3
Hi Greg,

I was surprised when I put a ammeter on the LGB coach lights and found that they are only drawing 1/3 amp at normal illumination (track power speeds) and just 2/3 amps at 24 volt (MTS?) voltage.

My thoughts are now changing a bit to the idea of fitting MRC AD322 decoders in the first coach to keep the MTS/DCC voltage and amps down when running under MTS.

That should make the light bulbs last a LOT longer and at a cost of only $10.99 per six coaches it should be a great way to control coach lighting - even shutting all coach lights off such as when a train is parked or to lower operating amps or when running outside in daylight.

Rather than match coach decoders to the loco decoders I may just assign a master Loco ID# just for coach lighting and key all coach decoders to the master ID#. On the other hand having matching loco/coach ID numbers would allow me to leave extra sidings under power with trains available but with locos, sound systems AND coach lights turned off.

I'm having fun with these $10.99 decoders and discovering applications for them that I had never anticipated.

I've looked at your web site and there is a lot of stuff there for me to browse through.

Regards,

Jerry
 

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2/3 an amp per car can add up pretty quickly, the USAT streamliners are about .75 amp each, so a string of 8 of them coule be 4.5 amps alone.

LEDs will make a lot of difference. I am confused on your statement about using the decoder in the cars, is it to be able to not run the lights when not needed?

Regards, Greg
 

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I added LED lights to three Bachmann J&S coaches. I used ball bearing wheels and installed a bridge rectifier and a large capacitor in each. Two five mm, bight white LEd's from Radio shack are more than enough for each car. I did the same thing for one Aristo heavyweight obs car, using in this case three leds. Four would have been better.



The capacitor keeps the lights from flickering. It works extremely well with the constant track voltage I use.

I recently bought some five m warm white leds, and when the aristo bulbs go I'll be putting the LEds in. My goal was lower current draw (I have not measured it) and long "bulb" life
 

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Discussion Starter #6
Posted By Greg Elmassian on 10/17/2008 12:16 PM
2/3 an amp per car can add up pretty quickly, the USAT streamliners are about .75 amp each, so a string of 8 of them coule be 4.5 amps alone.

LEDs will make a lot of difference. I am confused on your statement about using the decoder in the cars, is it to be able to not run the lights when not needed?

Regards, Greg


Hi Greg,

I was not clear. What I meant is that the TOTAL of all SIX LGB coaches was only 1/3 amp at normal power and 2/3 amp at 24 volts. This was much lower than I had anticipated. When I got such a low reading from the LGB Jumbo ammeter I used a second ammeter and got the same reading (under DC track voltage).

By placing the decoder between the tender and the first coach ALL the coaches lights will be controlled by the single decoder either to dim them or to turn them off. That should only require a single decoder per consist of six coaches.

So far I have not done this as I'm having a bit of a problem getting the first decoder programmed.

Regards,

Jerry
 

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Discussion Starter #7
Posted By lownote on 10/17/2008 12:27 PM
I added LED lights to three Bachmann J&S coaches. I used ball bearing wheels and installed a bridge rectifier and a large capacitor in each. Two five mm, bight white LEd's from Radio shack are more than enough for each car. I did the same thing for one Aristo heavyweight obs car, using in this case three leds. Four would have been better.



The capacitor keeps the lights from flickering. It works extremely well with the constant track voltage I use.

I recently bought some five m warm white leds, and when the aristo bulbs go I'll be putting the LEds in. My goal was lower current draw (I have not measured it) and long "bulb" life







That may work for me if two LED's are sufficient. I think the LED's would plug into the newer LGB light sockets and if wired in parallel perhaps a single rectifier and capacitor would work for the 6 coaches with a total of 12 LED's.

Thanks,

Jerry
 

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Discussion Starter #8
I finally got the first decoder programmed. I have problems programming because my laptop does not have a serial port so I have to use a serial port adapter and that gets a bit difficult to get to work with the LGB 55045 programming module.

Anyway so far it seems to be working well except the lights can still get too bright to suit me (even with CV 5 set to 125).

I may just set the decoder to the Loco ID# and let the loco speed also limit the light brilliance of the decoder controlled coach lights.

There is a bit of flicker with the lights being powered by the decoder motor output but that gives me 8 (controlled) amps available rather than the much lower light function output.

I think I am going to like this idea of AD322's controlling the coach lights. Track powered operations are OK as well since I don't care what polarity the decoder is feeding the lights.

A single $10.99 remote rheostat to control 6 lighted coaches is just what I need.

One nice thing is that with the decoder installed in the first coach (4 wires to connect) it is a super simple installation and once installed the coach/combine can be removed from the train and put on the programming track for future adjustments. Most of my 1st coaches are combines or baggage cars so hiding the decoder is not a problem.

Jerry
 

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Jerry, because the motor output is most likely PWM, that means pulses of full voltage, you will need to really cut CV5 back. Try an even smaller value. That should also give you finer control of the light intensity. Try 64 for CV5.

Remember that Aristo uses PWM in their power supplies to make lights come on "earlier" in locomotives.... so you are in the same boat, but trying to work against it so to speak.

2/3 an amp for 6 coaches is great, are you sure they are not using leds? How many lights are in each coach? In any case, good deal for you.

Regards, Greg
 

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If making your own light strips with 6 led's, and using MTS or DCC, wire them in series. 6 bulbs at 3 volts gives 18 volts, and add a resistor for 4.6 volts as the diode bridge will drop 1.4 volts.

At 10 milliamps, the resistor value would be 4.6 divideded by .010 giving 460, and the common resistor available is 470 ohms.

Now for Jerry and his bright lights at night, the value of the resistor can be increased which will lower the current, thus lowering the brightness of the led's.
 

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Discussion Starter #11
Posted By Greg Elmassian on 10/17/2008 8:38 PM
Jerry, because the motor output is most likely PWM, that means pulses of full voltage, you will need to really cut CV5 back. Try an even smaller value. That should also give you finer control of the light intensity. Try 64 for CV5.

Remember that Aristo uses PWM in their power supplies to make lights come on "earlier" in locomotives.... so you are in the same boat, but trying to work against it so to speak.

2/3 an amp for 6 coaches is great, are you sure they are not using leds? How many lights are in each coach? In any case, good deal for you.

Regards, Greg




Hi Greg,

These are the LGB 68333 light sets. They are not LED's but apparently do not use much current.

I had not thought about the PWM but of course you are right.

What I will probably do for now is to program each AD322 to Loco ID #1 (that will even work with Central Station 1's with only 8 Loco ID's available). Since I already have block wiring I can use that to turn parked trains (including their lighted coaches) on or off.

By programming all the coach lighting AD322's to Loco ID #1 that will prevent losing a bunch of available Loco ID's plus give me single ID control of all coach lighting. Since all the coaches have LGB 68333 light sets the same setting should result in the same illumination for all coaches along with being able to turn coach lights off without turning the loco off.

I always look for the cheapest and easiest solution so I will probably go with the AD322's and existing lights rather than convert to LED's but there may be other situations where I need a LED solution.

One nice thing is that once the AD322's are installed I'll be able to reprogram them either with the LGB 55045 programming module or with the LGB 55015 Universal Remote plus being able to control both locos and lighting systems under serial or parallel operations (my shop layout will probably be run with a Central Station 1 while other layouts will be run with Central Station 2 or 3's.

Thanks to both Greg and to Dan,

Jerry
 

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Discussion Starter #13
Posted By Greg Elmassian on 10/18/2008 8:13 AM
Maybe I am confused.

Jerry, the lights in your LGB cars are lamps or leds?

Regards, Greg


Hi Greg,

I think we were both writing at the same time.

They are filament lights not LED's and they are wired in parallel from the tender to the first coach and then from coach to coach so all lights are parallel and on the same circuit.

Regards,

Jerry
 

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Discussion Starter #14
Posted By Greg Elmassian on 10/17/2008 8:38 PM
Jerry, because the motor output is most likely PWM, that means pulses of full voltage, you will need to really cut CV5 back. Try an even smaller value. That should also give you finer control of the light intensity. Try 64 for CV5.

Remember that Aristo uses PWM in their power supplies to make lights come on "earlier" in locomotives.... so you are in the same boat, but trying to work against it so to speak.

Regards, Greg


Hi Greg,

I meant to ask if the PWM could be smoothed out with a capacitor such as used in Heinz Koopmann's circuit for adapting LGB's analog sound cars to work with MTS? In his circuit he puts a bi-polar 25 volt 220uF capacitor across the output of the decoder.

Thanks,

Jerry
 

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It's worth a try, are you getting flickering? You might want to use 30-35v to be safe (switching transients from the motor output transistors).

Regards, Greg
 

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Posted By Greg Elmassian on 10/18/2008 8:53 AM
It's worth a try, are you getting flickering? You might want to use 30-35v to be safe (switching transients from the motor output transistors).

Regards, Greg


Hi Greg,

There is some flickering which I can live with if I need to. I have some 25 volt capacitors but I don't recall finding any of a higher rating in bi-polar. If the flickering was a single coach it would be a lot less noticeable but with six coaches flickering in unison it is more noticeable.

Then too I have just begun this project so my results are not far enough along to make any significant decisions. Koopmann put a 220 ohm resistor across the 220uF capacitor. I''ll have to check and see what sort of resistance I am getting from the 12 - 13 filament lights for reference (if it means anything).

Jerry
 

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I'm going over some old ground here, and I know you know the first part, but I think it's good to have a complete picture for the rest of the people reading.

On "normal" track power, to avoid or reduce flickering, you use an electrolytic capacitor to "store" energy when the power is temporarily interrupted. Most times people use an ordinary polarized electrolytic, since they are cheaper, especially in the larger capacities and higher voltages. An easy way to make sure you have the right polarity is to put a full wave bridge on the track pickups, so you always have a dedicated plus and minus on the output of the full wave bridge. This works for DC and AC. Now you can go to your storage capacitor and to the lights.

But, when a capacitor is uncharged, it can draw a very large amount of current for a brief instant (as it absorbs a charge)... this can "trip" electronic circuit breakers or short circuit detection circuits.

So, you put a low-resistance resistor in series with the output of the full wave bridge (really makes no difference on the plus or minus side)... it only needs to be a few ohms, just to "take the edge" off this big current pulse.

Some systems don't need this, but it's a good rule of thumb when doing this kind of modification.

OK, in your case Jerry, you have a PWM signal coming from the decoder outputs. Filtering this with a capacitor is a tougher job, because you have on then off pulses, and at low "speeds" it's off a lot more than on.

Now you are calling for the capacitor to do a lot more "work", and you need it to charge rapidly, and have greater capacity to discharge and run the lights when the power is "off"...

So, the bigger capacitor will put more loading on the output drivers of the decoder. It really depends on how the decoder handles this.

If it were me, I would put a full wave bridge on the motor output (try a 5 amp one), and then put a 300 or 400 mfd electrolytic cap with a 100 ohm resistor on the output of the full wave bridge, and of course the lights. See how that works. The worst you could do is overload the full wave bridge, which should be cheap.

It might take a bit of twiddling, but this should get it, and allow you to reduce the light level with minimal, if any, flicker. You might be able to get away with a 1 amp FW bridge, but I think the inrush current to the capacitor would be too much. Also, using the FW bridge allows you to use a much less expensive polarized cap, rather than searching for a NPO one.

Hope this helps,

Greg
 

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Discussion Starter #18
Hi Greg,

That is a very good explanation and it covers things I had not thought of. As you know I am not an engineer (other than model train engineer) so I have to look to people like you who know what they are talking about. I understand what you are saying even though I could not have put the thoughts together myself.

For the moment I am probably going to focus on installing the decoders rather than on the flickering lights (not that I am any less interested) it's just a case of doing what will provide the maximum results with the minimum effort in the minimum time. Since the baggage & combine cars have plenty of free space and they are easy to assemble I will focus first on getting the decoders installed and programmed. There are somewhere around a dozen decoders that I may need to install not counting some loco decoders I have not yet got around to installing. Unfortunately my mind keeps coming up with new problems/projects long before I finish the ones I have already started.

Many thanks,

Jerry
 

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Discussion Starter #19
As an update I have now installed MRC AD322 decoders in several LGB Combines and Baggage cars (these were the 1st cars in six coach consists).

It seems I may have over reacted to the flickering lights. I suspect it was a case of looking too closely at a car (or consist) right in front of me. It is true that there is some noticeable flickering when I have the door open on a baggage car and there are lots of yellow walls to reflect and highlight the flickering but when the train has the doors closed and is moving a little distance from me the flickering lights are hardly noticeable unless I look for them (I doubt anyone else would even notice).

All in all I am extremely happy with the way this project is working out. A single $10.99 decoder is handling the 12 - 13 lights of the six coach consists very, very nicely.

I have decided to standardize all the coach lighting decoders on Loco ID #1 with the idea that since all the LGB coaches have LGB lights what looks good for one train will look good for other trains. Currently I've settled on power setting #4 to provide the level of lighting that I like best (others may have different preferences).

The installation could hardly be easier.

1. Two screws (one on each end of the combine or baggage car) and the roof comes off.

2. Next I unsolder the wires from the tender to the 1st light and instead solder the gray and orange decoder wires to that 1st light.

3. Then I use 3M UR or UY (solder-less and self stripping) telephone connectors to connect the decoder red and black wires to the wires from the tender. When connecting just a combine or baggage car I use the 3M UY's.

4. Finally I program the decoder to Loco ID #1 and CV-29 to #4. Once I tried the decoder before I programmed it and - NOTHING HAPPENED! Then I remembered that as shipped the decoders have track power turned off so unless CV-29 is set to #4 the decoder will work under MTS/DCC but not under track power.

5. On some trains I have a Drover's Caboose and the newest ones came from LGB with ball bearing wheels with track contacts. With those Drover's Cabooses I replace the ball bearing wheels with regular LGB metal wheels and I put the ball bearing wheels on the front truck of the 1st Combine or Baggage Car and connect the wires from the ball bearing wheels to the red and black decoder wires (same as from the tender). What makes this extra easy is that MRC provides two black and two red wires so a 3 way 3M UY telephone connector makes connecting the wires together literally a snap.

There are THREE MAJOR CAUTIONS:

ONE:

Since the decoder will then be connected to the tender and the ball bearing wheels are also going to be connected to the tender and input of the decoder - the Baggage Car or Combine MUST be connected to the tender with the end that is connected to the wheels and the decoder red and black wires.

Failing to do this WILL RESULT IN THE DECODER BEING CONNECTED TO TRACK POWER IN REVERSE (power input connecting to power output) which would probably instantly destroy the decoder (and I have no idea if it could cause further harm to the tender and loco electronics).

I intend to find some way to try to prevent my accidentally connecting my Combines and Baggage Cars in reverse. I may try color coding the connectors or I may go further by taping the connectors with RED tape to make disconnecting the tender impossible without first removing the red tape.

TWO:

As with any installation of ball bearing wheels or other track contacts - CARE MUST BE TAKEN TO ASSURE THAT ALL TRACK CONTACTS ARE THE SAME POLARITY WITH EACH OTHER AND WITH THE LEADS COMING FROM THE TENDER.

THREE:

Since the decoder is controlling ALL the coach lights, this installation can ONLY BE MADE IF THERE ARE NO ADDITIONAL TRACK CONTACTS AFTER THE 1st COMBINE, COACH OR BAGGAGE CAR.

If there is a track contact on any car that would connect to the circuit beyond where the decoder has been placed in the circuit (where it could feed into the decoder output) the decoder will probably be destroyed immediately and I cannot assure that further damage could not take place to the loco or tender electronics.

I have to say that I find it pretty slick to be able to remotely control (all) the coach lights on the main line (or shut them off) all at one time and with identical results.

Judging by the ammeter on my Jumbo it suggests that there is virtually no current drain through the decoder when the lights are turned off.

When running under track power the only noticeable difference is that the voltage needs to get up to about 5 volts before the coach lights come on. Once they illuminate they seem to work just fine with no difference from before the decoder was installed.

Personally I am extremely pleased with the results of this project and I intend to put decoders in a lot more consists but I am not recommending that anyone should do anything. If anyone reads this and decides to try it they should only do so if they fully understand what I am doing and are comfortable with how to do it. I think it is a super simple concept that works very nicely but it is totally based on the assumption that others have wired their coaches as I have done - by using LGB 68333 wiring harnesses to conduct power to the lights from the tender to each coach in line with the lights being wired in parallel.

I would guess that LGB would probably not have recommended this circuit because it is definitely not goof proof. Just reverse the baggage or combine car in the circuit and at least the decoder will be destroyed. I am willing to risk blowing a $10.99 decoder and I would not expect further damage to occur but this is a risk I am taking with my trains and I make no guarantees to anyone else as to their results.

If anyone wishes to challenge or question this circuit or how I am using the decoders feel free to jump in. I just do things that make sense to (or work for) me and if someone else believes they are not a good idea for any reason their comments would be welcome.

Jerry
 

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A quick way to make sure the connectors are permanently connected is to use heat shrink tubing on the connectors.
An exacto type of knife can be used to cut the shrink for repairs in the future.
 
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