How To Run Two TMCC Engines on Same Loop

I only have one Legacy engine, no TMCC. On my Legacy engine you can lock it in to one direction with the PGM/RUN switch by putting the switch to PGM while it is slowly going in the direction you want it to travel. This should allow you to kill all the power to the block which should eliminate the problem. In my engine manual it is explained under the 'Conventional Operation' section. That is, if I understood your problem correctly? 

I don't know if any TMCC engines have the sensors for the new sensor track, but I think the sensor track would allow this if the engine is so equipped? I don't have a sensor track yet either, so not exactly sure on that one.

I would never run my trains unattended.

you can run tmcc and legacy together but what usually happens is one will catch up to the other.  I have even seen legacy engines sooner or later catch up with the other one.

the best way I have found to run two engines on the same track is to have two legacy controllers so you are not switching back and forth. 

I have not found a simple way.

The way to run them is to do it in conventional mode, locked in forward, with block control.  You need to have at least three-four blocks each powered when the block ahead is not occupied.  The easiest way to do this is with insulated rails and relays powering the block behind.  When a train occupies a block, the previous block is unpowered.  When the train leaves that block, the power is restored and the one that the train just left is unpowered.  This goes all around the loop.  With that scheme, a trailing train can never catch up with the lead train, and the lead train will stop if it catches up with the trailing train.  If they have cruise control and are closely speed matched, it should be very seldom that the trains actually stop.

"I would never run my trains unattended."

OK, bigdodgetrain, I did not imply I was going to start up the trains and go have a beer.  I would just like to run two trains per loop while showing friends without having to do the "Fast Thumb Shuffle" on the Legacy controller to avoid collisions. 

Thanks rtr12 for your suggestion, I'm going to try that and will post the results.

Thanks for your suggestion "gunrunnerjohn" however when a TMCC engine enters an unpowered block, it will stop as desired, however it won't start back up when the power returns as as the previous lack of power shuts down the TMCC board and you have to then "readdress" the engine to get it running again.  This "issue" will not allow TMCC-Legacy engines to run unattended using this block system.

The LCS and sensor track are not going to solve this problem.

I have to defer to gunrunnerjohn on the sensor track, he knows a lot more about them than I do. I was mostly speaking in terms of operating conventionally, the way gunrunnerjohn describes above, which is how I interpreted your drawing above with the relay.

If I understand the problem correctly, you might want to experiment with multiple unit (MU) function. I would start by operating the Legacy units on one loop and the TMCC units on another loop. First, set up a MU. Next, separate the trains by desired space. (you can do this by using the engine ID). After the trains have been spaced, operate in the MU function. Hopefully this will help.

I have found that TMCC and Legacy engines sometimes do not play well together in a MU . Just experiment and have fun.

Hope this helps,

Woody

I did not mean to bust your chops I was just using the word "unattended" as you did in your original post.

I do not pretend to know what is meant only the words I see.

sorry. 

Can you tell me where I can read about MU (multiple unit) function?  I do not recall coming across that before. 

Lionel uses the word lashup for MU consists.  However, that's a dirty word here at OGR!

OK, I know "lashup" !!   I've done them with both a CAB-1 and Legacy controller using a powered "A" and "B" diesel unit.  Hadn't thought of that.  I'll try it. 

Guns,

   I have been up sense 0 dark 30 this morning so I may have missed something here.

Sense I am just getting into Legacy, maybe I am not understanding why addressing and running multipule trains on the same loop is a problem.  I would think it works similar to DCS, you address each engine in Legacy mode, start them up and run them at constant speed to not allow them to catch each other.  Is this not possible with Legacy engines on the same track.

PCRR/Dave

Hello Dave,

You are correct. I run two consists on my small layout quite a bit and they do require some attention so neither runs into each other. While the MTH DCS speed control is more accurate the same thing can be accomplished in Legacy.

First off is to get both engines started from the remote. Once started ramp up the forward speed of the first engine, I usually get the first engine to throttle 8 or 9. I then do the same with the second engine once the space between the two is sufficient. After that I watch each consist to make sure the speed is consistent and then just check on both once in a while. Running the two engines to fast will magnify any speed differences which could lead to having to adjust one engine or another sooner versus later.

Rick486,

You'll also have to experiment which engines will play well together. GRJ mentioned this when trying to find a pair of engines for an MU to pull a huge consist on the club layout.

Then, I think the visual spacing of the engine of one train and the last car of the second will make it easy to observe quickly if a Fast Thumb Shuffle is needed.

I recall your layout from last season. Very nice!

The other issue that I see that would impact accurate control would be the lack of power feeds on a carpet central layout. Each loop should have a power and common feed every 5 to 6 track pieces. Every 8 or 10 would be a help.

Doing this on a carpet layout would look like spaghetti, so playing with the lash-up speeds of trains that play together well on your setup as built is most likely the best approach. If you discover a problematic area, then a set of additional power feeds to only that area will avoid the spaghetti look.

With Legacy or DCS, it's not normally any issue.  However, the TMCC stuff is all over the map with speed curves, so it's a lot more difficult to find two that will run sufficiently close in speed.  Another point is that Legacy stuff has back-drivable gears so that the slower one just gets a helping hand from the faster one and doesn't put impossible loads on trying to push against something that it can't move.

You're right, with last year's carpet layout consisting of almost 300 feet of Fastrack and 10 remote turnouts, I had several irritating problems with dead track, in spite of running multiple power branches off lamp cord concealed under the Fastrack throughout the loop.  I'm not sure it was equal to every 5-6 track pieces though. 

Previously, I have separated my powered Santa Fe F3 "A" and "B" by about a foot and run them in "lashup" to see how their speeds coordinate and they mimic each other quite well.  As you know though, other TMCC and Legacy engines require very different speed settings on the Legacy controller to keep them running "even" on the same loop. 

My problem is that when I have company over, or more importantly, my train club (North Atlanta O-Gauge Railroad Club) over, I like to "show off" and have all eight trains running on the 4 separate loops of track (obviously 2 per loop) and if I don't talk to anyone, I can keep them separate.  But as soon as someone distracts me with conversation and questions---BOOM, I get a very embarrassing rear-ender and derailment.  Thus, my quest to find some way to run these without playing the "Fast Finger Shuffle" on the Legacy controller. 

This was the layout last year.  The two sidings in the upper right ran into the other room quite a bit to provide room to park one of the consists while the other ran "unattended".  All 4 loops had similar sidings for this purpose.

Rick,

I was considering some wiring configurations to supply sufficient power. I went to a voltage drop calculator and used 18AWG(Lamp Cord) at 18VAC with 8A. The voltage drop is significant for even a 17.5' length.

Improving this will certainly help matching and maintaining engine speeds.

What do you use for the power source?  Are the receptacles along the fireplace wall switched on the same circuit?

Should I go to 14ga for the wire to power the track?  Would sure love it if the track connections were so good that I'd only need a 2' wire from my transformer, which BTW is a ZW with 4 bricks.  One brick (180w) is dedicated to each of the 4 individual loops with block power separators where turnouts connect loops.  Thus, each loop is assigned a separate circuit: A, B, C, or D on the ZW.

The ZW, 4 bricks and Legacy controller are all hooked to the same receptacle near the lower right edge of the above layout design.  I use the fireplace recepticles for village lighting and the Christmas tree.

I have used 14ga on one or two loops (which are about 30' from end to end but the wire is so dang thick, it's hard to keep it concealed under the track and my wife hates it when I drill holes in the living room carpet !!

That's sort of what I wanted to hear. I was thinking of dividing the layout into four power with one brick directly attached to each power division and physically near the section. Each brick would power a fourth of all loops. Still grinding on that, but it would use shorter run of a heavier gauge wire. I am kind of passing on this one.

Idea number two.

Put the whole layout on 1/2" foam insulation board. then you could wire underneath of the foam board as if your layout was on a permanent table. You could paint the topside. 8'sheet cut to fireplace wall to edge length, 4' width for number of sheets for the end to end.

A two motor train will draw between 2-4amps. Run two engines on a loop and some incandescent lighted cars and you need some heavy wire.

Here's the voltage drop calculator to give you some idea of why the trains are losing power. Even with one train at two amps, 18awg as a main supply is not going to work.

Run 12awg bus down the center, 4 colors and one common and take about 30 sets of feeds 3 per track x 4 tracks (12) on the ends and whatever you need in the center for all four tracks and you'll solve your power issues.

How do you do that on a large floor layout? The money question.

The issue you are addressing is why I switched from TMCC to DCS to use the "ALL" command which starts all my DCS consists simultaneously.  You can use a pseudo "ALL" command for Legacy (TMCC) by not having any MU's and use the "TR" Legacy command. After starting the trains with the "TR" command, use the "Eng" to address an individual train. I run up to 4 trains per loop (13 loops) using this (Proto2) with the fastest train leading with the last train on that loop being the slowest or being a Legacy consist as the or 3rd or 4th train. While none of the engines run at the same exact speed, you can get 3 or 4 trains (running at 10 smph) over a 17 by 7 foot loops to run between 5 and 15 minutes before the slack between trains needs to be adjusted.  Legacy is much better at this speed with three speed steps per one DCS smph for road engines. Switchers (my genset) runs at speed step 22 - 23 with my DCS Proto2 4 MU consist at 3 smph.  This permits fine Legacy adjustments to permit maximum time before you have to adjust the slack. Subways run around 43 speed stops to a DCS 20 smph.  When I am running 33 consists simultaneously, I have my friends each with a controller and each controlling a single loop.  I am usually running 3 or 4 loops myself.  If I was starting over, I would most likely not have MUs and just run Legacy engines with the "TR" function because of the fine speed control available with Legacyl. TMCC engines have less speed steps and would not be my choice to control multiple engines on a single loop with minimum operator intervention.

Newer Legacy stuff has an "all" setting, engine 99.

just dreaming, but it would be awesome if Lionel added something like an arduino to its LCS system. The sensor track could send info about block occupancy, speed, and direction to the arduino.  It then could calculate the appropriate speed adjustment and send Legacy commands through the SER2 to slow or speed up trains or even switch to a passing siding. won't help in this case, but fun to think about. 

a sensor track might work if you have enough ir engines. Setup a recording that loops through having one engine on the line and one on the siding.  Once the first engine triggers the recording the second engine comes out of the siding.  The first engine enters the siding.  The second engine then triggers a new recording, and the first engine comes out and the second returns to the siding.  Rinse and repeat.  You could have eight engines going intermittently.    

Mike, sounds like a great project, when are you starting it?

That is quite a Christmas layout, (2009), & the one currently planned.

Rich,

A very nice layout in the making. As to your question, we have never been able to get any two engines to run for a large period of time without distance creep. Two of the identical TMCC locomotives? One is always faster a touch. With postwar pieces we were (almost;-) always able to stop the faster one with the dead block. When run by humans, we always get the inevitable crash Even Legacy, MTH Proto 2 & 3 units might be off a hair. Depending upon your cushion for error... A crash might still be inevitable. We gave up on keeping a small current to not cycle the e units when stopped, and as someone mentioned above, we never leave them un attended as cruise equipped locomotives just work harder when hitting a stopped train. Tires, motors, boards, etc. are not worth the risk.

Looking forward to your solutions and images.

Here's the Christmas layout from last year.  Didn't feel up to crawling around on the floor for a week this year....maybe next year.

Rich

Excellent video!  I like all the trains running at once.  That is the way I like to run mine.  Keeps you on your toes!  The background Christmas music adds a lot to the video.  You have a very nice Christmas layout.  Thanks for sharing.  Ken

Now that's a Christmas layout!