Swicth contact points

The only thing I can think of and this has happened to me, is the contacts within the switch itself aren't super good and they lose contact. I have some older Atlas switches and that did happen. I was able to drop a very tiny drop of solder onto the hinge of the point rail and the connecting rail, just enough as to not stop the hinge from working but enough to make good electrical connection and that solved the problem.

Just a suggestion.

Contact poiints

Hmmmmm. In the past, when I had that problelm, you could "push" the blades to make good contact. I'll check, but the lamp shows positive power on both rails on both sides of the frog and before and after the switch itself. 

I'll try anything at least once. If it works, I'll try it more than once. Thanks.

Locomotive issue?

Have you ruled out an issue with the locomotive?  

I had one short wheel base locomotive that was very temperamental when negotiating through turnouts unless I held it above a certain speed.  A sister locomotive could crawl through the same areas without issue.

Also, what type and brand of turnout are you using?  Insulated frog, non-insulated frog.  Atlas, Micro-engineering, Etc. 

Joe

"On some (but not all)

   Since it retains sounds and lights I'd think this is a mechanical problem, the loco just needs a bit more current to overcome the drag of the turnout curve or gauge of some parts of the rails? ......DaveB

Multiple throttles

Do you have multiple throttles?  If yes,  is the loco selected on two throttles? 

If yes,  you will see the behavior you're describing as Digitrax wil keep cycling between the speed setting on each throttlle.

Hope you are able to figure it out. 

John C

Gauge check

Just a thought, have you checked the clearances of the turn-out and the back to back of the wheels, using a N.M.R.A. gauge? 

From what you said the sound lights etc all stay on. You have check the continuity of the power and it appears to be all o.k.

As the loco only "stalls" at low speed, the gauge of the track or back to back clearances may be causing the engine to "stall" at that location.  You could also check the drive shafts and see if they are tight against the flywheel or motor.

Can not think of anything else that would cause the problem.

Hope this is of some help.

Turnout Issues

David, Let me ask you a bunch of silly questions?

First I'm guessing you are using Atlas turnouts with plastic frogs?

Do the turnout pass the quarter test? The quarter test is, without any locomotives or rolling stock on the track, place a quarter across the rails to see if the command station detects the short. As soon as the command station beeps, remove the quarter. Check to make sure the points of the turnout pass the quarter test as well.

If all is in order, have you used insulated rail jointers or gapped the rails at any location where there is a turnout? If yes, is there a chance the wiring is reversed on either side of the insulated rail jointers? 

As others have mentioned above, have you checked all clearances at each turnout using the NMRA gauge? The issue maybe mechanical and not electrical?

What happens if you run the locomotive at half speed entering the turnout, does it stop, does it slow or continue on at half speed?

Let us know what you find?

Checking suggestions

Thanks for the input. Tomorrow morning I will gauge the rails and wheels. When I do wiring, the rail away from me is wired positive (blue wire) and closest to me is negative (red wire). Each goes to a separate terminal strip marked pos and neg and each of those is connected to the PSX-1 appropriately.

I've given some thought to putting each loco (I tested 2 with the same results) back on the programming track and checking the settings. I'm going to re-clean the wheels and hit the track one more time. The track is Code 83 with Peco Insulfrog turnouts. Have had no trouble using the same setup on the East end of the layout. Have not powered the bridge that spans the manway door and connects both parts (East and West end).

Will keep you posted. Any other ideas would be appreciated. Thanks.