What is the max amount of feeder wires on a layout you can have without interfering with the DCS Signal?
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One feed pair per block. Block length has been the subject of debate for years, but keep in mind that the signal degrades across track joints.
I had an 8' x 18' layout with 2 main lines. Each had their own TIU channel and only one track feed per loop without a break anywhere except between the 2 loops. Not a single problem. The track was MTH Real Trax.
Since my layout is a 5' x 14' layout with two loops connected by turnouts, I didn't think I needed to use any blocks. I have one MTH Steam PS3, and I want to run a LionChief Steam Engine on it, too. Would one feeder wire have to be use on the inside loop, too? And would that be enough power running through the track for the LionChief Steam Engine? I'm also using a Lionel power supply 180W.
I don’t think there is a maximum amount of feeder wires. The minimum recommended is one feeder pair per block with a block being 10 to 12 track sections as I recall. If you have long track sections such as 37” flex track, you need fewer feeders than if you use sectional 10” track sections.
I would start with at least one feeder per loop and see how it works. Your 180 watt power supply should be enough for two locos. Use 18 gauge or larger wire.
I've seen recommendations for all sorts of stuff, here's a few of lines from Barry's DCS O Gauge Companion, gives some guidelines for wiring.
- Attempt to limit the number of track blocks or sidings from a single TIU channel to no more than 12 - 15.
- Limit track blocks to no more than 11 or 12 track sections where sections, long or short, all count. If
sections are all short, consider soldering connections between sections to make longer ones. Regardless,
track blocks should not exceed 100 feet in length. - Use home run or star-type wiring.
I would never use 18-gauge wire for track feeders in O gauge. I have found it diminishes signal strength as well as being inadequate to carry train power loads. My layout uses 6 TIU channels and has about 75 toggle-switched blocks. 14-gauge wire.
I'm curious how you found that #14 for the short track feeders had better signal characteristics than the same short track feeders using #18 wire. There's no rational reason that should be the case AFAIK.
John, I have no short track feeders, because every block is controlled via toggle switch on the control panel. Such a setup is essential for running several locos conventionally, whioch was what my layout was built for in the early 90's. Some leads are short, some long.
I did originally have some distant yards fed through multi-conductor 18-gauge cables, on the theory that when I went there, I'd have a hand on transformer throttle anyway so could overcome voltage loss. When I added DCS, I found those yards got very poor signals, so I rewired them with 14- gauge and have no signal problems since. Seems to me that when you try to squeeze a signal with a large power current into a small wire, the signal has to be affected.
That's what I find odd. The DCS "signal" is a very low power affair, the only thing the wire size should affect is the voltage drop to the distant connections, I can certainly see that a voltage drop could cause issues.
I'll probably be using #18 wire for soldering to the track and dropping through the layout, then I'll have #14 for my power wiring. I can't imagine that causing DCS signal loss, but I guess I'll see.
Multi conductor cable is not ideal for data. Signal bleeds into surrounding wires sometimes. Signals are best isolated somewhat. Shielded helps tons.
Signals can also get lost in too large a wire, solid wire, etc.
It's far more likely that impedance mismatches and signal reflections cause DCS issues, that was the whole genesis of the "magic lightbulb" and the Deat's DCS filters.
Multiple feeds to one section or loop can lead to signal looping. One feed towards the center of each block is ideal for dcs if I recall right (Barry)
My experience is not with dcs really, but a few other data transmission forms. It also worked when my bosses said it wouldn't shouldn't couldn't... then they changed the systems cables nation wide.
Of course they never told me why.
Adriatic, all my blocks but one have a single hot feed, near center of block. That one got a temporary second feed 15 years ago because of a poorly conducting UCS track, and still works fine. When I used multi-conductor cable, there was no data.