I’m a noob, drafted into helping my father, also a novice…
My father has two TMCC equipped Lionel sets, and I just got him the CAB-1 (and command base) as a gift. Both sets were the standard oval sets with CW80 transformers. Now that he has the CAB, he’s gung-ho about setting up a single TMCC layout for both trains (as opposed to two isolated tracks).
I know it’s unlikely a CW80 can sufficently power both trains, so what I’d like to do is set up two blocks, each powered by a CW80. According to the TMCC guide, Lionel makes it sounds as if this is posible as long as I insulate the center rail, but I am concerned about what happens as a train passes from one block into the other, momentarily connecting the blocks. If both of the CW80s are powered to max, and I keep the tracks in phase, is this a reasonable way to keep the track powered sufficiently, or am I in danger of screwing up the locos and transformers when a train passes from one block into the other?
Without some knowledge of how they are programmed, it’s hard to say what will happen. There are questions of how they will handle fault currents due to any difference in open-circuit voltage between the two transformers inside. There is also a possibility that, when they are connected together, one will try to take all the load anyway, defeating your purpose.
Sure you can. I would do it. I am doing it now with two PM-1 PowerMasters to power the big streamlined F-3 ABA sets on one track. And I run conventional, so I am changing the voltage, it would be even more straightforward w/ 2 CW-80’s powering a TMCC command layout. You don’t even need the seperate blocks/power districts, just make sure they are the same version, and phase them per convention & wire them in parallel, keep the power up full all the way, or even better use the Accessory posts & program them for full power so they can’t be changed by accident. You now have a 10 amp track power supply.
Any slight power setting imbalance by trying to “backfeed” the triacs will essentially be ignored by the lower set transformer, and there will be no imbalance once the load comes on & draws off triacs in both CW’s. If both are programmed for full power just as you suggest, they will be equal.
Depending on what trains you have…I would start with just one transformer. It will probably power both no problem. Unlike conventional (voltage controlled) operation, you do not need (nor want) blocks when running TMCC. The digital signal will decide which trains stop and go (not the voltage).
Thanks everyone, for the suggestions. As far as why not two loops? Actually, that was my suggestion, but my father wants one unified layout for both trains, and I want to amke sure I don’t fry his locos In terms of using blocks, I know you don’t technically need them for TMCC, but I was concerned a single CW80 wouldn’t have enough juice for more than one train. However, I didn’t realize I could just wire two of them up in parallel. That sounds like a great way to amke sure I have plenty of power.
In terms of wiring them in phase, I just need to ensure they’re both the new version CW80, correct?
Rob, unless the two CW80s are triggering their triacs at exactly the same time, one will come on earlier than the other and will supply the entire load at least until the other comes on, regardless of how great that load is. Do you know that that momentary overcurrent won’t trip the current limiting, leaving the tardier CW80 to supply all the current?
I would consider starting with just one transformer. I would set up the tracks with separate lockons and insulated pins with two blocks. Then I would run both sets of wires back to the one transformer. If I found I had plenty of power I would leave it as is. If not (trains go too slow or red light on CW-80 flashes), then I would just remove one set of wires and hook up the other transformer (or better yet just wire the two in parrallel with each transformer to both lockons). I would definately make sure I had both old or both new CW-80s and I would plug them both into the same powertap that I plug into the wall.
I’ve never noticed it with the PowerMasters wired in parallel. I’d like to see two CW’s, wired in parallel at full power, and switched on with a master switch, on a scope.
Unfortunately, I won’t have access to a scope at the time, or I’d try it out.
For my own clarification, am I correct in my assumption that unlike the CW80s, the PowerHouse supplies can be wired up in parallel or in blocks without trouble because they are a fixed voltage power supply as opposed to transformers (unlike the CW80s)?
It’s certainly more straightforward, but be aware that the PowerHouse bricks have mechanical circuit breakers and that it is possible to do some light welding in the time it takes for them to trip. Two bricks, even 135’s, is a lot of juice. Run them in parallel, but use the direct connect lockons, PowerMasters, or TPc’s for protection.
Upon further review, I am thinking of using the CW80s for accessories, and convincing my father to get a single PowerHouse 180 and a direct connect lockon for power. Should he need more power, since he’s only running TMCC engines, it seems to me like the easiest/safest route for more power would be to set up a second, isolated district with another PowerHouse 180 and direct connect lockon (instead of running them in parallel with a TPC400 and a single power district).
As I mentioned, I’m a noob, and am trying to absorb as much as I can about all the ways to power a layout, and how the different transfomers and supplies work - but I’m still not familair with how the PowerHouses actually provide power to the track. But since they’re both fixed voltage supplies, it seems to me like this would alleviate Soni’s concern of backfed current as the train passes form one district into another, as long as they are wired in phase. Am I correct about this?
Most of todays trains draw very little in the way of amperage. Most of my freights are just over 2. Passenger trains are around 4 to 5. What many people overlook is the smoke units. Run with the smoke off and turn it on with the remote and you will see the meter jump about 1 amp. This may not be every type but I see it in my MTH steamers. I think 1 180 watt brick would be more than enough for 2 starter sets. Any doubts as far as protection. Just add a Radio Shack fast blow 10 amp fuse. If the layout turns into a longer single track mainline. You may want to add more connections as far as feeds to the rails.
As far as running on 1 loop. I do the very same same thing. Sort of a folded dogbone that has trains passing one another on what appears to be a doubletrack mainline. You can add passing sidings as well if the layout grows. If your dad is interested in opperation down the road this may be the way to go.
In terms of using blocks, I know you don’t technically need them for TMCC, but I was concerned a single CW80 wouldn’t have enough juice for more than one train. However, I didn’t realize I could just wire two of them up in parallel. That sounds like a great way to amke sure I have plenty of power.