Home made LED upgrade for Lionel 260 Bumper

Ron045 posted:

 

Last year I purchased some LED bayonet bulbs for a couple of my Lionel 260 bumpers.  I got them at a train show for $2 each. 

Today one of those LED's burnt out. 

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If someone sees a potential problem with what I did, please feel free speak up and correct me.

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Hmm.  Kind of makes one wonder what's so good about LEDs if they burn out in 1 year! 

As you know if you've been following this forum that LEDs are polarized devices.  There is a school of thought on this forum, of which I am a student, that if driven by AC track voltage one should protect the LED so it doesn't see the reverse polarity from AC.  Typically this is done with a 2 cent diode so it adds another component but it should all fit within the bayonet base.

stan2004 posted:

There is a school of thought on this forum, of which I am a student, that if driven by AC track voltage one should protect the LED so it doesn't see the reverse polarity from AC.  Typically this is done with a 2 cent diode so it adds another component but it should all fit within the bayonet base.

And the beat goes on...  We need to get a choir group together to sing this every day.

I have used LEDs powered by AC, but the voltage should be kept to 12 volts as most prewired LEDs that I have had experience with run on that voltage.  It could be that the higher voltage we use for our trains cooked the resistor.  

Stan2004 posted that LEDs do not like reverse polarity.  I didn't realize that.  Usually, when I am building something that uses LEDs I check them before I install them by hooking them to my DC power pack.  If they don't light when the knob is turned one way I simply turn the throttle the other way.  So far none have been damaged using this method.  

Dan Padova posted:

Stan2004 posted that LEDs do not like reverse polarity.  I didn't realize that.  Usually, when I am building something that uses LEDs I check them before I install them by hooking them to my DC power pack.  If they don't light when the knob is turned one way I simply turn the throttle the other way.  So far none have been damaged using this method.  

The damage is cumulative, it doesn't happen all at once.  When they're running AC, they're getting hit with reverse voltage sixty times a second.  Since the reverse voltage specification for most LED's in in the 5V range, the negative peaks from 18 VAC are far above that.  Even the negative peaks for 12VAC are over the 5V reverse voltage limit.  Here's a typical LED specification sheet, these are the absolute maximum ratings.

I know someone who was using LED's soldered into the bases of burned-out incandescent bulbs years ago (1990's) in his signal bridges.  I'm not certain what kind of voltage he ran them at, but I don't recall anything about resistors or diodes inserted in the circuit (he just poked one lead through the solder in the tip while it was heated with an iron, then soldered the other lead to the outside of the barrel).

I do know the LED's on his control panel flickered like they were being powered with AC (you could see it whenever your eyes swept across the panel). I don't know how many failures he's had. I'll ask about that next time I visit.

---PCJ

If he didn't have current limiting and ran them on more than 3 VAC, they lasted about five seconds!  He clearly had current limiting somewhere.

Don't believe me?

Connect a bare LED across a 12 VAC source and see how long it lasts.

gunrunnerjohn posted:

If he didn't have current limiting and ran them on more than 3 VAC, they lasted about five seconds!  He clearly had current limiting somewhere.

Don't believe me?

Connect a bare LED across a 12 VAC source and see how long it lasts.

I wonder how many LEDs died over the last 3-1/2 yrs with 12VAC at their terminals?  I'm bettin' a few did!

I just killed one the other day, it was bright, then just glowing red, then dead.

Is there a good source for replacement bayonet and screw base bulbs for Lionel trains that are LED?

this looks good BUT I don't do any electrical work until it passes the GRJ test and has the GRJ seal of approval!.

*GunRunnerJohn*

Wow... My thread gets a reboot 4 years later.  So here is an update.  After I did that bumper I did the others. 

4 years later, they still shine bright.

I even upgraded these rocker switches.  I purchased the incorrect switches and could not get them to light. 

@Windy City posted:

Is there a good source for replacement bayonet and screw base bulbs for Lionel trains that are LED?

If you type "Town and Country Hobbies" into your favorite search engine, you will find what you are looking for.

@Ron045 How did you solder inside of the tiny base?  Are you using a diode in the mix as others suggested above?

@JD2035RR posted:

@Ron045 How did you solder inside of the tiny base?  Are you using a diode in the mix as others suggested above?

I held the heat on the outside of the bayonet.  Applied a little solder to the inside.  Tinned the leads.  Then applied heat again to the outside and inserted light.

I did not install the diode for this project.  However as a result of the feedback from this thread, I have purchased some for other projects.

Now that it was brought up again, I'm sure Murphy will arrive and all the lights will fail this week.

Ron

Town and Country offer a replacement led light to fit the 1445 bayonet bulb used in 022 switches. These should be plug n play for the 260 bumpers.

Rod

Agree with the above recommendation on Town and Country Hobbies. I have directly replaced many of my Lionel accessory lighting with their bulbs. They have been reliable and bright.

http://stores.towncountryhobbies.com/

Great suggestions, quick and easy to buy an LED bulb and replace an incandescent bulb.  

Thank you

While I have not seen photos of the guts of the T&C 1445 LED replacement, I'm fairly confident that T&C is on top of the internal diode issue. In this OGR thread, the wedge-style T&C LED replacement is shown to have the diode.

In this OGR thread, the OP reports a stunning 64% failure rate after one year in a 1445 LED replacement from some un-named vendor at York show.  Dissection showed no diode.  And in this OGR post, how about an abysmal 100% failure rate in green 1445 LED replacements after one year...possibly the same un-named vendor.  No photos in the latter case but I'll take side bets on what is (or isn't) under the hood there!

I replaced all the bulbs in my Lionel 072 switches with 18V versions of LED bulbs from Town & Country. It's been 3 years and had one bulb fail. The bulbs work great and no more melted switch lanterns (I drive the switches at 18V in order to ensure a secure throw of the points).