Powering a Large Layout

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I am in the process of building a large, suspended Lionel "O" gauge system in my basement family room. When completed it will be about 16' x 16', with a small outside "bulge" or outside loop on one corner of it. I don't expect to have any lights, switches or anything else, it's just going to be a conversation piece. Will I need something besides a standard-issue transformer for it?

Any advice would be greatly appreciated!

A standard transformer should be just fine. What you will need on a layout that size is a heavy gauge power bus and multiple power drops around the layout to prevent excess voltage drop when the train is far from the transformer.
CSX Robert

Thank you very kindly for the quick response! Since I'm kind of a member of the Kindergarten Class as far as these things go, can you provide me some specifics as to where and what I would buy for the heavy gauge bus and how many drops I'd need? If I can avoid burning anything down or popping circuit breakers I would have a much better experience with my wife. :)




HO & O (3-rail) trainman
I'd use 12 or 14 gauge for the bus, and 16 or 18 gauge for the feeders, every 3 to 6 feet. What's the wattage on your transformer?

OK it looks like from what I've been reading this old transformer is unlikely to have enough wattage to power this large of a layout. So from what I'm reading I should be looking for about an 80W transformer, does that sound correct?

Also I've found some info about using a bus and feeders, but I'm a bit confused. It seems like (and I freely admit I could be wrong) that I do this "bus and feeder" thing for the ground wire but NOT the hot wire? Am I missing something?

Again, sorry for the kindergarten questions and I appreciate everyone's assistance!

Best Regards,



HO & O (3-rail) trainman
I have a loop in my room that is 15.5'x9.5'. A little less track than you. I had the stock Lionel transformer from the 1950s, which I think is either 25 or 35 Watts. I had a single bus with 4 feeders along perhaps 2/3 of the line (the other part didn't allow for a bus because the other third spanned two lift outs). The only "slow" spot for the loco was the farthest from the last feeder, which was in the middle of that non-bused area. It wasn't terribly slow, but enough to notice.

I went ahead and upgraded to TMCC, and use a 180 W Power House brick, because I wanted to be able to run 2 TMCC equipped locos at the same time.

I think what you got is probably enough to run one conventional loco, and have a bus (one line for positive, one for negative) with feeders at 4' max. If it doesn't do what you want, though, an 80 W power pack should do it.

What track are you using? I used Fast Track, and although it is nice and easy to use, it's pretty noisy. In fact, standard Lionel track is noisy too. If you've got room for some foam underneath (or cork roadbed) the track, it will help with noise.

Gents, based on the conversation so far and what I've read, I cam up with this diagram of what I THINK I'm needing to do:

Feedback is appreciated!


... I cam up with this diagram of what I THINK I'm needing to do:
You got it! - In your diagram the red and black lines will use the "heavy" (buss) wire and the blue connections to the track (feeders) the lighter gauge wire.

Just make sure the feeders are all attached to one side or the other (!)


OK it looks like from what I've been reading this old transformer is unlikely to have enough wattage to power this large of a layout...
This size of the layout has no direct bearing on how large of a transformer you need, all that really matters is what you will be running with it. Larger layotus do require a heavier bus than smaller layouts. If your bus is to small, you will experience voltage drops at the far reaches of your layout, but you will experience those drops regardless of the size of your transformer.

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