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I recently added a second TIU to my layout and I'm having problems with Super TIU mode. Both TIUs are Rev. L running DCS version 5.00.  In super mode, my locomotives show a good signal (9-10) , but they don't respond well to commands (speed, horn, start up, etc.). If I switch back to normal mode, everything works perfectly. The locomotives will even go between blocks controlled by different TIUs. Should I just leave the TIUs in normal mode? Will this cause any problems if I add additional locomotives?

I read the instructions in Barry's book and in the MTH guide, and here is what I've done:

1) Reset my remote and both TIUs (only 1 TIU powered on at a time)

2) Changed 1 TIU address to 2 (confirmed 2 light blinks on startup)

3) Powered up second TIU and added as 1 (confirmed 1 light blink)

4) Set both TIUs to super mode

5) Added 2 PS3 locomotives on track controlled by TIU 1

6) Experienced poor response to commands from remote

7) Switched both TIUs to normal mode and everything worked fine

 

 

 

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John,

It sounds like you set up Super TIU mode correctly

Some initial questions:

  • What version of DCS are you using?
  • Are you certain that there is no center rail connection between tracks connected to one TIU and tracks connected to the second TIU?
  • Do you experience poor control when one one TIU's tracks or on both TIU's tracks?

 If I switch back to normal mode, everything works perfectly. The locomotives will even go between blocks controlled by different TIUs. Should I just leave the TIUs in normal mode? Will this cause any problems if I add additional locomotives?  (something amiss here)

I'm a super mode runner with 4 tiu. No problems going from one tiu zone to another with version 5

 In normal mode you should not  be able to run from one tiu zone to another without deleting and re-adding or using the "read " to move the tiu/engine association.

Robert,

I'm surprised when you indicate you don't lose control in normal mode when going from one TIU's area to another.  Are you sure that the two areas aren't electrically connected other than common ground?

That's why I asked him "Are you certain that there is no center rail connection between tracks connected to one TIU and tracks connected to the second TIU?"

If there is a connection, that could explain things. Since Super TIU mode sends all commands for all engines to all TIUs instead of only to the TIU with which an engine is associated, in normal TIU mode only TIU #1 would get the commands. Since all of his engines are associated with TIU #1, if TIU #1 was connected to all tracks, control could be good over the entire layout.

However, if all TIU's tracks were connected in Super TIU mode, the engines would get multiple, identical commands, causing indeterminate behavior.

While this is certainly "uncharted territory", it could possibly work for smaller layouts with only a single source for track power.

Interesting!  

Last edited by Barry Broskowitz

I checked the center rail and it is isolated. I use homerun style wiring, and I have about 50 blocks. I have about 10 blocks connected to each of the 4 outputs on one TIU and another 10 connected to the fixed 1 output of the second TIU. All of the track connected to the second TIU is in one area and there are only 2 places where it connects to track from the other TIU. I use Atlas track, and I have plastic rail joiners on the center rail between all blocks. I am using 2 Lionel 180 watt bricks connected directly to the TIU inputs for power.  One brick is connected to 2 inputs and the other is connected to 3 inputs.

 

Dave,

Are Both TIUs set to Super?

Did you add TIU 2 to the remote?

He stated:

1) Reset my remote and both TIUs (only 1 TIU powered on at a time)

2) Changed 1 TIU address to 2 (confirmed 2 light blinks on startup)

3) Powered up second TIU and added as 1 (confirmed 1 light blink)

4) Set both TIUs to super mode

It looks like he did things correctly.

From my experience, Super TIU mode works well. We've had multiple TIU's in place on the club layout for more than a decade spanning several versions. A few key points:

  • Make sure no one is using a 900Mhz cordless phone or other device. It will kill the radio signal from a nearby TIU or remote. This will no longer apply when the new WiFi software that supports Super TIU mode is released. We obtained one of the "other devices" when we bought an NCE DCC system for our On30 section. The wireless mode of the controller operates on 900Mhz and it knocked out two TIU zones near the On30 area. We use it tethered for now.
  • Make sure there are NO center-rail (or buss "Hot") connections between the TIU zones. This will cause track signal cancellation problems. Also check to make sure that you don't have a TIU channel connected out of phase (check your plugs/connections) . Electrically, the track can be in phase, but a backward TIU will cause you some issues as the signal will be going out onto the common side (your Proto-3 engines will respond to that TIU if it's the only one running). Don't ask how I found this out.
  • Always add/edit your engines and build your "Lash-Ups" (sorry Rich) to only one of the TIU's, preferably TIU #1. We actually put another TIU-1  on the workbench in the staging yard for this purpose and use a tether so as not to interfere with trains running on the layout. In testing, I've found that a "Super TIU" temporarily tethered to the remote will handle additions more efficiently as the remote will only talk to that TIU when tethered rather than polling the other TIU's.
  • Make sure your RF board in your remote is securely seated. If it's loose, the radio signal gets weak. I put a piece of foam between mine and the remote case years ago and it has worked great for over 14 years. I haven't opened up a REV-L TIU, but I've had to re-seat the RF board on a TIU before (foam works here, too).
  • Always perform a "Read" when you power up the layout to ensure the remote knows the TIU's are out there.
  • Operate from a central position within the layout if your TIU's are located at a distance. In our case, the TIU's are somewhat spread out so the middle of the layout area is the "sweet spot" that hits all of the TIUs

One point on Lash-ups. In Super TIU mode, one quirk I've found is if there's an extended loss of power to the lash-up in a TIU zone other than the one where it was created, you may lose a locomotive in the lash-up. It's not consistent. The work-around is to select and start each member locomotive separately, then select and start the lash-up. If one of the member locomotives isn't found, you'll have to take them back to the zone where the lash-up was created and re-start it. I'm the only one at the club that runs DCS lash-ups.

Last edited by AGHRMatt

Matt,

In Super TIU mode, one quirk I've found is if there's an extended loss of power to the lash-up in a TIU zone other than the one where it was created, you may lose a locomotive in the lash-up

That was corrected in DCS 4.20 and DCS 5.0.


DCS Book CoverThis and a whole lot more is all in “The DCS Companion 3rd Edition!"

This book is available from many fine OGR advertisers and forum sponsors, or as an eBook or a printed book at OGR’s web store!
johnf posted:

Greg,

I tried your suggestion and there is no power to the section covered by the second TIU when it is disconnected.

 

AGHRMatt,

I tried the read button and both TIUs were recognized. My DCS performs well with just one TIU but has very poor response when I add the second. I may try connecting everything to just one transformer.

Your last reply to Matt might be  something .... Are all the power supplies in phase???

 Measure the voltage,  center rail to center rail where tiu1 zone  and tiu 2  meet.   There should be little or no voltage. If around 38 volts power supplies are out of phase. Yep center to center rail.

Good point, As RJR mentioned you have to pull the aux jack completely  from the tiu else the tiu thinks it's still plugged into the wall outlet.

Question for all..... can you check the fuse with a continuity meter  with one lead on the black input and the other lead on the black out put.? (  not counting the original G.) The fuses are on the black side right?

I solved my super TIU problem. I hooked everything up to just 1 transformer (Lionel 180W brick) and it works perfectly. Anyone have any thoughts as to why my previous setup didn't work. Here is what it was before:

- 2 Lionel 180 watt bricks (they were definitely in phase because I checked several times)

- 1 brick connected to Fixed1 and Fixed2 of TIU #1 and also connected to Fixed1 of TIU #2

- 2nd brick connected to Variable1 and Variable2 of TIU #1 (both set to fixed voltage)

- Both TIUs also powered by 18v external power supply

Barry Broskowitz posted:

Matt,

In Super TIU mode, one quirk I've found is if there's an extended loss of power to the lash-up in a TIU zone other than the one where it was created, you may lose a locomotive in the lash-up

That was corrected in DCS 4.20 and DCS 5.0.


DCS Book CoverThis and a whole lot more is all in “The DCS Companion 3rd Edition!"

This book is available from many fine OGR advertisers and forum sponsors, or as an eBook or a printed book at OGR’s web store!

We're at 5.0. Still happens on occasion, but less than under versions 3.x-4.2

To clarify my point if I understand this situation correctly is I believe in your original configuration connecting brick #1 to both TIU's and having an additional brick #2 connected to TIU #2 may have caused an imbalance in relationship with keeping the center rails isolated between the two TIU's, if that makes any sense. Just a thought. 

John,

My commons were connected through the outer rails, but there was not a direct connection before the TIU. Could this have made a difference?

No, that was not a a problem at all.

1 brick connected to Fixed1 and Fixed2 of TIU #1 and also connected to Fixed1 of TIU #2

That would have created a direct connection between two different TIU's channel inputs on the Hot wire, and could have been the cause of the problem. However, I cannot say one way or the other with certainty since I've never seen that particular situation before.

If the channel outputs were directly connected in that way, it for sure would have caused some issues.

Matt,

We're at 5.0. Still happens on occasion, but less than under versions 3.x-4.2

While I can't say what is actually going on at the club layout, I can say with a high degree of certainty that itis not the bug that's causing the problem. If it was, the problem would not occur "on occasion", rather, it would occur every time.

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