Questions on taking the DCS Plunge

[luther_stanton]

Hello all!

I currently have an around the room layout in a 9 x 12 room.  It is 99% Atlas track (some is the older black tie steel track for magnatraction and some is the newer nickel rail) with some tubular on sidings for accessories, etc.  I have TMCC installed and working without problems.

I am strongly considering taking the DCS plunge and have seen some postings about wiring patterns and types, etc.  I am curious if DCS would work well with my current configuration and what I would need to get DCS up and running.  I would like to operate DCS in addition to TMCC, not in place of.  Here are some particulars:

The layout is broken into four power blocks – each is 10 to 12 feet of track.  Each block has a 12 gauge stranded wire carrying 14 volts “hot” (center rail).  Each 12 gauge feed terminates near the physical center of the block and is tied to 3 or 4 14 gauge wire drops, each of which is soldered to an Atlas rail joiner on the center rail.  So it is really neither a bus nor a star type schema.  All the 12 gauge feeds join together at a single point which is tied to a single Lionel TPC 300 and 180W Power House.  

Each block also has an isolated outside rail controlling (through relays) various MTH and Lionel signals.  All common (outside rails) are tied to a continuous bus that runs completely around the layout.  All power – track, accessories, lights, etc. ties to the same bus.  All power (the TPC,  2 older Kline PowerChiefs and a single Lionel Accessory transformer) are phased and tied to the common bus. I also have 2 SC-2 driving some of the switches as well as some accessories.

I built the power blocks so that I would have flexibility to use multiple TPCs to drive individual blocks and also support conventional (non-command) operation.  I have implemented neither since a single TPC / POHO has worked fine and I have only purchased TMCC motive power thus far.  I usually have two – three engines on the tracks but only one is actively running at any one time.

I added multiple feeders for each block so that there was a power lead on all sides of the switches, both sides of uncoupling tracks, etc.  I realize now that the number of power drops may be excessive, but I have had trouble free operation for 2 years.

So the million dollar question – will DCS fit into this set up?  Is there any chance it would drop in without any wiring modifications or would I need to significantly change my power distribution to a pure star schema with twisted pair to support DCS operation?  Will I need to replace my SC-2s and if so with what - AIUs?  Can the AIUs and SC-2s be installed in parallel so that I still have the same level of CAB1 control?   

I appreciate any thoughts / suggestions.

- Luther

[jefelectric]

There is a lot of info on the DCS section in the other guys forum, but here is my experience.  The best advice seems to be try it first before making any changes.  I had a similar setup as you do before I added DCS.  I put in the DCS and it works great, with a few exceptions.  I had to add a few light bulbs in some areas.  Don't know why this works but it does.  If you don't have the DCS video, do get yourself a copy.  I have my switches set up on SC-2s and continue to use the Cab-1 to control them weather or not I am using DCS.  I don't see this as a problem.  There is a wealth of info out there to help you.  Don't forget to use a separate power supply to power your TIU, it makes life a lot simpler when you have to trouble shoot a problem.  I use the one recomended in the DCS video, sold by Radio Shack.

[Dave Connolly]

 I've had DCS pretty much from day one. Certainly have had issues but most are easily resolved. Will it work on your layout ?  The only answer is to hook it up with no modifications and proceed from there with testing. It may work perfect or your layout may need some tweaking. Certainly not rewiring. I have an older common ground with buss wiring. Took a few weeks but it runs fine. My only advice is to remove everything from the layout such as TMCC engines, cabeese, lighted cars etc. . When you test for signal strength throughout the layout run only DCS engines. Often times certain TMCC engines as well as some lighted cars adversly effect the DCS signal. Many seem to think they need to rewire and thats not the case.

 DCS has been around long enough that you should have no trouble getting it running. Plenty of knowlegible people on it who can speak from experience. Many like myself were not set up to run DCS following it's guidelines but still have got it working.

[ChiefEagles]

Probably so.  Working great on mine and it runs into two rooms.  Trying it.  You'll be glad you have both.

[phillyreading]

To add DCS you will need at the least the DCS base and handheld remote, the TMCC to DCS cable from MTH.  To power a TIU you may find an MTH Z750 power brick(without the variable control) on sale at a train show or hobby shop for a few dollars, that is what I did.

Don't know how everything will work and if you are able to use the Cab-1 with DCS, or parallel the SC-2 and the AIU-personally I don't think that you can parallel them.

From everything that I have seen about DCS & TMCC being used together was from an MTH DVD, so things may work for and things may not work for you.  Best thing to do is refer to what either Lionel or MTH instructions or DVD's tell you.

Lee F.

[chuck]

The TPC can not be accessed from DCS. It will have to stay controlled by TMCC. You should also plan on the two systems being completely separate as the cable used to tie a TMCC Command base to a TIU will block signals to your TPC (or any other serially controlled device). This is both a software issue (DCS only supports ENG commands, no TR, no SW, no RTE, no ACC) and a hardware cabling issue. The TIU to command base interface cable is kind of wonky. It should be able to pass through serial commands but you would need to make a custom cable to do this. You can get AIU's and wire up switches and accessories in parallel or dump your TMCC units. Your choice. You could put the TPC on the shelf and try to control your conventional loco's with the DCS variable channels but you will be limited to 180 watts per channel, 32 speed steps and a much higher starting voltage than what the TPC offers. Again, your choice. You probably should consider running DCS in "passive" mode with an aux power supply like a Z-750 used to power up the TIU and then take the output signals off the track side of the TIU. Unlike TMCC, isolation pins in the center rail will block the command signal. You need to run signal feeds to each seperate block. DCS also handles signal transmission better with balanced or paired wiring. Aka the runs of hot and return should be same length. This is what is meant by "star" wiring and it is very different from the more traditional toy train bus wiring used on many layouts.

[luther_stanton]

Thank you for all the replies, suggestions and information.  I think I will definitely be moving forward in the next couple of weeks.  I am sure I will be back with more questions once I start the installation.

Thanks,
Luther