Adding DCS to a Legacy Set Up

Roy,

My question is - could you take the wires going from the Direct Lokon, which would otherwise connect to the track, and connect them to the fixed input 1 or 2 of the TIU and then take the two output wires from the TIU to the track.

Yes, you can. Just don't connect the "one wire" from the Legacy Base directly to a TIU channel input.

This and a whole lot more is all in "The DCS O Gauge Companion 2nd Edition", now available for purchase as an eBook or a printed book from MTH's web store site! Click on the link below to go to MTH's web page for the book!

Thanks Barry,

It's good to have confirmation that its ok to do it that way and not have to cut the plug off the PH180 and I guess, still leaves a safety device installed ?

I downloaded your book from MTH's website yesterday, plenty to read and learn, Its great to have someone with your wealth of knowledge to 'call on', much appreciated.

I understand the "one wire" connects to the TIU's output common depending on which one you use - not a good idea to leave it connected within the Direct Lokon then ?

Thanks again

Roy

Roy,

I understand the "one wire" connects to the TIU's output common depending on which one you use - not a good idea to leave it connected within the Direct Lokon then ?

You can connect the wire anywhere you like, as long as you avoid running the Legacy signal through a TIU channel. Connecting it to the Lockon is fine.

Be aware that all TIUs except the original Rev. G do not have the channel Common wires connected.

Right ok, to be on the safe side I'll connect it direct to the track common.

Thanks again Barry

Roy

Barry, is it acceptable to wire the channel commons together on the output?  I'm assuming there is no phasing issue with the input power.

John,

is it acceptable to wire the channel commons together on the output?  I'm assuming there is no phasing issue with the input power.

Yes.

Roy...  It is really really easy to integrate them.  I use DCS to control my MTH and conventional engines as well as all the accessories and switches and Legacy for my Lionel and TMCC engines.

Hello Eric,

You're right, I didn't realise how easy it was going to be and have just had a 20 minute session running one of my new MTH GP30s alongside a couple of my legacy engines. Now to read Barry's book in more detail and maybe just have a flick through the MTH catalogue !!

Thanks again all

Roy

I took a TIU and a couple of remotes to a fairly large layout and just connected it to the existing feeds to the power districts.  Plopped a couple of MTH locomotives on the track and away we went.  The only glitch was the Lionel Direct Lock-On is not compatible with the TIU, had to remove those to get it to run.  Since the TIU has circuit protection on the outputs, that's not really a loss.  Both Legacy and DCS stuff ran like a top over the whole layout.

Sometimes it is that easy.

That's interesting ! Mine is working fine via the Direct Lokon.

However, after reading and rereading Barry's posts to my question it did occur to me that the 'one wire' from the Legacy base finds itself connected to the common within the Direct Lokon, so unless you disconnect the 'one wire' from the lokon and attach it either directly to the common rail or the common output of the TIU it's going to be connected to the input side of the TIU which is not desirable. Just wondered if thats why you couldn't get it to work ?

Roy

The Legacy base was connected directly to the track, it doesn't go through the lockon.  The direct lockon was on the output side of the TIU when it caused problems.  The DCS signal made it through enough to keep the locomotives from coming up in conventional mode, but you had no control.  Removing the lockon solve the problem completely.  I'm sure the TMCC direct lockon on the input side wouldn't be an issue.

Roy,

Doesn't the Direct Lockon connect directly to the rails? If so, connecting the "one wire" to the Direct Lockon is just like connecting it to the TIU's output channel Common. This does not pass the Legacy signal through the TIU.

Or am I missing something?

Since I've never used a Direct Lockon, I can't comment as regards John's contention of incompatibilty between it and the DCS signal.

Barry, the TMCC Direct Lockon connects between a transformer and the rails in a typical Lionel environment.  It's basically a fancy electronic circuit breaker. 

Since they were already in place and wired to the track, I had just connected the output of the TIU to the inputs of the individual lockons for each power district.  The device obviously interfered with the DCS signal as it didn't communicate at all.  Removing the lockon solved the problem. 

Since the TIU provides the same functionality, the TMCC Direct Lockon is redundant in this case anyway I would imagine.

The Legacy signal was connected directly to all the track commons, so that wasn't an issue in this case.

The reason for my experiment is we want to use DCS as well as Legacy for our modular club, so this was our "trial run" to see what kind of issues we would have.

Hello Barry,

The way I set it up was to leave the Direct Lokon in place.

Within the lokon is a socket in which is plugged my Power House 180. There is also a connection for the 'one wire' and two terminals to attach the wires which will go directly to the track- live and common, the 'one wire' is directly linked to this common terminal within the Lokon.

I've then taken the live and common wires from the Lokon, which would normally go to the track, and directly plugged them into the TIU's fixed input, except that I removed the 'one wire' from the Lokon and connected it directly to the track as you told me not to connect the 'one wire' to a fixed input (which had I left it connected within the Lokon it would have been going through the TIU's input channel)

Then I've taken the live and common wires from the TIU's output channel to the track.

I could draw it for you if it would make my explanation any clearer.

Roy

Roy and John,

No problem, I think I "get" it.

Thanks!

Roy, in your scenario, I don't see any reason for the TMCC Direct Lockon unless you're taking the TIU out at times.  The PowerHouse 180 has a good electronic breaker, so the TMCC Direct Lockon is redundant as near as I can see.

Hello John,

I think my main concern was that by leaving the PH 180 attached via the lokon I would be sure that I had the correct power connections to the track, if I went ahead and cut the plug of the PH 180 I wouldn't be sure which was the live and which was the common. Plus by leaving the lokon in place I thought might be an extra safe guard - I have noticed very often in the past that when I switched on the PowerHouse 180 the RED light on the lokon came on for about 3 seconds or so before changing to GREEN I'm not sure if this is normal or not and I came to the conclusion that it happened because of the initial surge of power. Maybe you could put me right on this, I'm probably worrying unnecessarily.

Roy

OH, I never cut the plugs off of a PH transformer, I hope you didn't think I recommended that!  I have a little jumper cable that goes from the Molex connector on the PH to the dual banana jack for the TPU.

I suspect you may be right about the TMCC Direct Lockon, I've never connected them with the TPU in the circuit.  Our modular layout test was the first time I tried, and that didn't go well.

I am sure that the Direct Lockon is redundant in this instance.  I would be a bit nervous about it tripping when I powered up.  I've never had the PH180 trip when I power up connected to the TPU.

If you buy the download from MTH can you print it out or do you have to read it online only? I might just buy the book if thats the case.

You can print it, but it's probably cheaper to buy the print version if you want it in print format, especially if you want the printout in color.  Also, the print version is probably more convenient than a home printed copy.  If you have a laser printer, it's probably not prohibitive to print it, but most inkjet printers clock in at 8-10 cents a page, for 215 pages that's the price of the print version.