Z-4000 Transformer

Are they connected in any other way... other than wires? Like by track/switches? Are these truly completely independent loops? Is it just the display showing the voltage and amperage, or is it powering trains on that track too? What happens if you unplug just one or the other transformer?

Yes, the track is connected by switches.  And yes, either throttle will run trains on track 1 or 3.  This has never been an issue in the past.  I just don't know what else to try.

If I unplug one, the powered transformer still runs the train.

could you have something that has fallen onto one of the switches causing feed back to the other Z4000?

OK, then you have a bridged center rail somewhere by a metal object - a lost part or compromised fiber pin / block delineation.

What kind of track are you using,,, and are all outside rails common to each other electrically?

There is no metal anywhere.  Ran a train on each line and had no shorts and each train ran fine by itself.

I'm an S Scaler.  Using American Flyer track.  I don't have any blocks set up.  The only pins I have are on sidings and the sidings power is working fine.

It wouldn't show up as a short to ground/common, but it's certainly a short to the other power district across a rail gap that looks  OK but is bridged by metal or debris of some sort.

How do you isolate each loop/throttle/power district? Do you have any reverse loops?

No reverse loops. 

The thing is track 1 and track 3 are not next to each other.  Track 2 is in between them and has no problem.  Track 1 (outer most track) is left throttle transformer 1.  Track 2 is right throttle transformer 1.  Track 3 is left throttle transformer 2.  And track four is elevated track with no switches and is right throttle transformer 2.

You will have to go to your wiring bus and one at a time disconnect feeders until you find where the connection is. Is it possible a recent short caused wire insulation to melt two wires into a junction? I have seen this happen... and you are running 10 amp power districts.

Without a track plan we are guessing. You say you are using Gilbert track and turnouts. Do you have all the selector buttons on the turnouts set to "2 train operation?" Is it possible one was moved to "reg operation?" Depending upon the track plan and wiring this could cause the symptoms described.

Think of three ovals.  The outside oval has switches going to the middle oval.  The middle oval has switches going to the inside oval.  This worked fine for years. 

Yesterday I moved three of the switch controllers (not the switches themselves) and the switches work fine.  All switches are powered by a separate transformer (i.e., not either of the z4000 transformers).

Middle oval works fine.

Outside oval and inside oval are trying to run simultaneously. 

There is no metal touching anywhere to any track.  I have not touched the "Reg Oper" / "2 Train" switch on any switch.

The middle rails are making contact with one another somewhere.  

It's funny that I should see this post.  Just last night one of my non-derailing turnout machines that has worked fine for the last two years started snapping back and forth wildly when a train began passing through.  

This switch machine is attached to a Gargraves switch.   My two frog rails, also the dead rail in my non-derailing circuit, had come into contact with each other.  There is a "flange" of rail that sticks out horizontally on all Gargraves rails.  These two rails in very close proximity to one another miraculously moved themselves together after two years.  I took a screwdriver and "split" the rails forming a gap.  Problem solved.

I know nothing about your switches, but I do know when a transformer starts doing what you are describing the rails are touching somewhere or you have a train that is parked across sections of track that are controlled by opposite handles of the transformer.  The train is bridging the gap and connecting the transformers together. 

That seems to leave only the possibility of the wires that connect Loop 1 and Loop 3 to their respective binding posts touching somewhere. Rob discussed that above. 

Gene P posted:

Yesterday I moved three of the switch controllers (not the switches themselves) and the switches work fine.  All switches are powered by a separate transformer (i.e., not either of the z4000 transformers).

Well, you're going to have to backtrack & undo the only changes you made and start there.

Thanks for all the replies.  I have no wires touching anywhere.  Checked each one.  I have no trains on any track so there is no bridging of tracks.  When I put one train on either track one or three, both transformers still try to move it.  All switches are turned to their individual track, i.e., three independent ovals. 

Out of ideas.  Thanks again.

Have a great holiday.

Based on your description this is a real headscratcher. Were it my layout I would diagnose by first setting all the turnouts for running on their 3 individual loops if they are not and see if the problem still exists. If so then remove the 690 track clips from all but line 1 and then see what sections of track see voltage. If handle 3 still operates line 1 then there is a circuit through yout track and turnouts that needs to be repaired.

If not then there is a connection that developed somewhere in the wiring. In this event add back the 690's for track 2 and see what happens. If the layout works normally add back the 690 clips one at a time on loop 3 to see which one is the offender. 

The challenge is it happened spontaneously. There are several ways I could intentionally make this happen with turnout and track clip configurations. 

Disconnected all the 690 clips for Track 3.  Track 1 and 2 work perfectly. 

Connected each of the five 690 clips on Track 3 one at a time individually and had the same problem with each one individually and all together.

Disconnected all the 690 clips for Track 2.  Track 1 and 3 work perfectly.

Any ideas?  I'm fresh out.

If there are 5 690 track clips on one loop and multiple 690's on the other loops that is likely causing the problem. most of the 690 clips on each loop are probably on the frog side of turnouts. For the 2 train feature to work correctly the power must be fed from the point side of all turnouts. To see what I mean go to americanflyerexpress.com and open the 1949 instruction manual. Figure 17 on page 24 shows the 690 in the correct location. If power is supplied to the two tracks on the top it will bypass the 2 train feature. In complex track plans and where a frog side of one turnout faces the point side of another this is difficult to avoid. The simplest solution is to use fiber pins or similar insulating pins at all the crossover locations on your layout as shown in figure 13 on page 18 of the Gilbert instruction manual.

On some layouts I have built, the fiber pins can be avoided by placing a 690 on each of the tracks on the frog side of the turnout and using that as the power source to feed the rest of the 690's on the track in that route.

Thanks Tom.  I have been running this layout for years with no problems - - never having moved the 690 track clips.  All of the 690 clips are on the outside rail of each respective oval.

Back to this topic for a second.  Can someone explain to me how if I power track two (the right throttle for transformer 1) there is no power transferred to either track one nor track three - - the way it should be.  But if I power track one, it does not power track two  - - the way it should be - - but powers track three?  And vice versa, if I power track 3, it does not power track two - - as it should not - - but powers track one?  If I'm having this problem (the thought being there is a problem with track two somewhere) when I power track two how is the power not transferring to track one and/or track three.

How about if you go with the process of elimination - have you tried switching throttles with track two & track three at the transformer(s) to see if the problem follows the transformer or the layout wiring?

I have not tried that.  I guess I can give that a shot.

If I have the same problem, what does that tell us?

It's unlikely to be the same problem, just similar.

So far, all signs point to a physical connection of hot(non-base) rail wires of #3 & #1 loops somewhere between the transformer and the track.

Gene P posted:

Disconnected all the 690 clips for Track 3.  Track 1 and 2 work perfectly. 

Connected each of the five 690 clips on Track 3 one at a time individually and had the same problem with each one individually and all together.

Disconnected all the 690 clips for Track 2.  Track 1 and 3 work perfectly.

Any ideas?  I'm fresh out.

 

Well, I think meter testing for continuity is the way to go.

I have only just recently handled a 690, but I don't think they could fail to short, based on how they are constructed.

Therefore, with the 690's removed for track 3, I believe that you will find continuity between the rails due to a rail insulator failing.

In AF wiring all of the outside rails are tied to common or the base post. Same for the Z-4000. All of the black are tied together.

So, short an inside rail to a sleeper/tie and current can flow. Why it flows to Z4K #2, I can't say.

But, what's important is that a path exists somewhere in the track.

I believe if you test TR#3 rails for continuity, it will be there. Finding where it is could be time consuming.

Another practice that I've adopted is to tin the ends on the wires to a lock-on and put at least one in from the inside, placing wire insulation between the posts to prevent a connection. I bend the end to a 90° with needle nose pliers at the insulation for a good fit.