Lionel Electro-coupler question

Unless this is a brand new design, many times a 1uf 50V NP across the coupler will solve electrical noise issues. A number of times folks here we've had threads where it was mechanical issues in the couplers, maybe that's what's happening here?

This subject has been asked about multiple times, but for some reason doesn't show up on a search.

Anyway, the short answer from someone who's had this happen, is that the typical usual problem is a bad coupler that needs replacing. Putting a cap on it is helpful and is usually done at the same time.

There's also a test to see if the problem is mechanical or electronic. You disconnect the wiring to the coupler and see if it keeps on malfunctioning.

This is one of the easier train problems to solve as far as that goes. Good luck.

If you are comfortable removing the pin holding the knuckle inplace, there is a a spring and plunger. If the spring is weak or short, or the bore was a little too long, the plunger may be barely holding the knuckle shut. I strech the spring (a small amount) and put it back together. Even if stray voltage is inducing a movement in the plunger, now a greater electromagnetic force will be required to move the plunger. Nothing a deliberate firing of the coupler can't over come. This has solved these issue for me.

What seems to be poppoing up more and more is Legacy engine with coupler issues. Something has changed, or the die for making the couplers are getting worn. G

From personal experience:

This is almost always an electrical/electronic problem, not a mechanical one -
but certainly try the mechanical fixes first (like graphite lubricant squirted
behind the knuckle). It can indeed be the machinery.

It can be electrical - literally a wire bare in just the wrong place and touching
the tender frame, etc (had that on a Weaver brass 4-6-2 upgrade).

It can be electronic - a board component has a shielding problem and gets zapped (technical term) by normal
layout electronic noise. Make sure that the boards and plugs are tight, etc.

A capacitor (see above) across the coupler leads can solve it - or not; worth trying.

Sometimes it just goes away; dirty track can add to the issue if it's a marginal problem.

My PT tender (wireless tether) on my "old" 5344 Lionel Hudson will do it - sometimes. Hadn't done it for a while,
then last week: opened. But that's not the tender the loco was born with; the old V'bilt coupler never gave
a moments problem.

It's infuriating; fortunately it appears on a small minority of locos. Mechanical couplers can
"just open" also, if they have issues. (Of course, they're cheap to replace.)

Thanks everybody. I will try these things.

Have you run it with the sound off to see if you can hear the coupler "buzz" when it opens, indicating an electronic issue versus a machanical issue.

Seems to be working fine now.

I had dome some layout work and the track may have been dusty, and someone mentioned that that could cause this problem.

I've found that with all the different levels and grades crossing next to each other, when I run Legacy engines without a battery, or when the battery is low, the sounds crackle at particular spots (Faraday Shields caused by the other tracks perhaps? Kind of like the chicken mesh tunnel problems). I'm wondering too if the dust interruptions, like the Faraday Shields, might cause the uncoupler to trip, and if having a battery installed will prevent this.

I'm going to put a battery in and will report back after a few sessions running it like that.

Other than the bare coupler wire shorting and fully energizing the coupler coil, the mechanical fix also reduce any spurious electrical noise because the noise has to be strong enough to overcome the force of the spring.

Tapping the truck from underneath can some time identify weak springs. If the coupler opens relatively easily with a tap, the spring is usually weak or short. Seems like many of the recent issues brought forward have been with the legacy engines. G

quote:

Originally posted by pennsy484:
Seems to be working fine now.

I had dome some layout work and the track may have been dusty, and someone mentioned that that could cause this problem.

I've found that with all the different levels and grades crossing next to each other, when I run Legacy engines without a battery, or when the battery is low, the sounds crackle at particular spots (Faraday Shields caused by the other tracks perhaps? Kind of like the chicken mesh tunnel problems). I'm wondering too if the dust interruptions, like the Faraday Shields, might cause the uncoupler to trip, and if having a battery installed will prevent this.

I'm going to put a battery in and will report back after a few sessions running it like that.

Note that the battery is only for the Railsounds, and has nothing to do with the couplers or their operation.

quote:

Originally posted by gunrunnerjohn:
Note that the battery is only for the Railsounds, and has nothing to do with the couplers or their operation.

Good point.

quote:

Originally posted by Harvey Henkelmann:

Maybe some day, but now that would be really boring for me. Postwar at Christmas time is the time for that for me.

The electrocoupler random firing issue can be traced back to electronic noise coming from one of two sources.
1. The armature of a pullmore. Or:
2. The roller pickups sparking.
The caps on the armature of a pullmore-equipped TMCC engine or the installation of a cap on the electrocoupler lead will act as a shock absorber and soak up these spikes in current path. Think of the capacitors as shock absorbers in your car, that prevent road jolts and pothole bumps from reaching the passenger compartment. Capacitors absorb and soak up jolts of electricity from momentary loss of contact of the roller to the rail like your tire/wheel/shock bouncing down the road (Only in the case of our trains we see a pretty blue spark) and level out the current flow to the rest of the circuit. Simplistic, but I hope it clears up the purpose of the capacitor mod.

quote:

Originally posted by D500:

Sometimes it just goes away; dirty track can add to the issue if it's a marginal problem.

quote:

Originally posted by Jim Battaglia:
The electrocoupler random firing issue can be traced back to electronic noise coming from ... The roller pickups sparking.

I got sloppy with my cleanup. I just found that I had forgotten to vacuum up a lot of saw dust in a couple of areas. So bad was this issue that one of my other engines wouldn't even make it through these areas without completely losing power. I've cleaned this up and everything is fine.

Thank you to all of you who have posted such helpful information! Even the non-dust-related information is so valuable moving forward! This is a great forum!

quote:

Originally posted by Harvey Henkelmann:

Wanna' sell all that electronic "junk"?

quote:

Originally posted by pennsy484:

quote:

Originally posted by D500:

Sometimes it just goes away; dirty track can add to the issue if it's a marginal problem.

quote:

Originally posted by Jim Battaglia:
The electrocoupler random firing issue can be traced back to electronic noise coming from ... The roller pickups sparking.

I got sloppy with my cleanup. I just found that I had forgotten to vacuum up a lot of saw dust in a couple of areas. So bad was this issue that one of my other engines wouldn't even make it through these areas without completely losing power. I've cleaned this up and everything is fine.

Thank you to all of you who have posted such helpful information! Even the non-dust-related information is so valuable moving forward! This is a great forum!

I think we all take for granted keeping the track clean form time to time. The best part is that you followed up Jeff, and the "cause and effect" will still be useful to someone at some point, and ultimately the best fix is the easy fix!

Sorry to revive this old thread.  I'm lost on this conversion.  How do you wire in the Cap.?  Hot wire?  Ground wire?

Right across the two wires to the coupler.

Either right at the 2 pin wiring plug, or maybe at the board connection, whichever is easiest.

 

Rod

I usually wire them at the board if the bottom of the plug is accessible, otherwise splice them into to leads at a convenient point.

Thanks for the replies.  I'll mess with it later in the week.  It is an older electro coupler from the 50's.  I have the power wire from the slide shoe hooked to the circuit board.  I was thinking of taking the ground wire from the electro coupler frame & hooking it up on the circuit board.  To see if that would help on the random opening of the couplers.  Looks like stray voltage pops it open.  It works like it is suppose to with the TMCC, except for random openings