I read 51.1 volts....solved!

You have a wiring problem. Just start tracing wires and eventually you'll fifnd it.

Thank you for the reply, appreciated.

Barry, please keep in mind that the track and wires have been down since the middle of Dec, and all ran well prior to this week. Since it is a temp layout, nothing was rewired/changed since then.

Also, while the drawing is crappy  and not clear, there is really only one feed to that section of track. It is shown at top left mainline...a Z feeds that mainline section over to the insulated section on the right of the mainline switch, over where the other Z feeds the right curve on the ML.

Thus the only way for power/signal to get to that circled siding is via the mainline switch, then via the rails of the switch that feeds the siding. Pwr from that first/left Z moves through both switches and terminates where the rail is broken on the 5" track before the bottom switch. With the inner rails of switches not conducting anything, I used gnd jumpers on both outer rails.

Having said that, I agree with you. It all worked well, then went south. I think that now signal is not getting to the siding like it should. Voltage obviously is, per the meter readings. If it were permanent, I would run a feed to the siding and probably cure it. Since it comes up Tues, I won't. Though today...I may take alligators and temp jumper from mainline to siding to see if it is cured.

I do find it interesting that 3 different PS2's will act the same, but give different readings. Plus the signal reading of 10 is confusing. But you are right, the engines coming up in a conventional type mode does indicate signal/wiring problems.

And though I do not have the "bible," if you look where the feeds and the broken center rails are,  I do think that I wired it up properly when I did it back in December, not sure what happened here this week. All works fine on any other section of track on that board. I believe that unplugging all other transformers except the Z feeding this section shows that nothing else is interrupting the signal to the 30" track....but I could be wrong about that.

If I run the jumpers, I will post results. Thanks again, Greg

Greg,

Try replacing that section of 30" track with a different one.

Could be something that was isolated in December is not isolated now. It could be due time ,climate conditions in your room etc.

Try moving all the spots where you have insulated rails. A clue could be the fact stuff is coming up in conventional which means something without a DCS signal. Maybe some light or accessory voltage became attached to that track.

My gut feeeling is the power for the switch machine is on that side of the rails.

Try powering down stuff until you get a normal voltage.

Well, lotta research this AM. Won't bore you but here is the gist of it.

DCS is wired correctly. On the left side of the crappy dwg above, the outer main line comes back down to a switch...that is back to back with one feeding that inner loop/siding. Two back to back switches.

Regarding those two switches on the bottom left NOT shown: between them is a 5" piece w/ the center insulated, and a 4.25" piece. Inner/outer rails gnded end to end.

Since Dec, all worked well. Now it appears that one of the outer rails carrying the gnd on the realtrax 4.25" has decided to intermittently NOT carry gnd from the tab underneath and thus from one end to the other. At times, no good gnd is getting to the section w/ trouble. UNLESS done w/ car wheels.

If I use an alligator jumper and jumper across the rail, all works.

The clue to solving this was the track signal button .....but not the way you would think. Use it and the engine sounds pulses twice or so, and then you hear "ticks" that correspond to the remote blinking the 10 or whatever.....on a good track.

On mine, no noise on test, even though I get 10's on the siding and the remote blinks.

And, on a good track, when test is turned off, the engine comes back up with sound. NOT on the track w/ the bad gnd. It comes up silent and the sound is set to the lowest volume. You have to hit vol up to get it back so you can  hear the engine.

I was running a string of cars off of the siding during a "quiet" test, and the engine started to tick. Moving cars turn the tick on and off. I then started w/ the VOM and alligator clips, but the best test was the cars....they completed the gnd.

Jumpering a good gnd from the mainline over to the siding gnd gives "noisy" signal tests, again w/ 10's. The showing of the 10's during the initial tests yesterday and during the quiet tests, is what I can not understand/explain. It means you can get a good test result, but still have a problem....or so it seems.

Yet the so-so gnd would still run the engine.

I will put a jumper in there after lunch and see if I get good, consistent results, and if that really solves the problem.

Thanks for all the suggestions, Greg

Disconnect the TIU output and read the voltage on the output terminals without any load.  I had the same problem on two seperate TIU's     Its the Power FETS in the TIU

Sorry Blue, it is not. I just got back inside from testing and thought I would report, when I saw your post.

Sometimes, it is the simple things. Two lockons, 8" of wire to jumper the gnd from the outside track to the gnd rail on the siding...to make up for the loss of gnd in whatever track joint it is.....and all is well on the C&GW RR again. How about that?!! 

No engines start in conventional  when they should not, they all read 9 & 10 on that section, the sounds "tick" when the track is being read, the sounds resume when the test is done, the voltage on the Z1k reads 17.9 by the remote, headlights, reverse and shutdown behave normally.

Now....go figure why the gnd worked enough to run everything, but did not "run" it right so the DCS signal passed by correctly. Some kind of electronic magic here maybe. Maybe a lesson here somewhere?

I hope you did not unnecessarily have your FETs replaced! Luckily for me, my FETs are good...nothing else maybe, but they be OK.

Greg