Seaboard Central 2.0

[C855B]

It's cold, that stuff will stay away.
...

Good luck with that. 

Stuff evolves. I read a report last year that a cold-tolerant kudzu strain has emerged and is heading our way. 

[packers#1]

Good luck with that. 

Stuff evolves. I read a report last year that a cold-tolerant kudzu strain has emerged and is heading our way. 

haha, well then looks like you northern folks will enjoy scenery like a typical drive down a southern highway...makes life interesting for sure 

[davefoxx]

Minor update as indicated on this week's Weekend Update:



As can be partially seen above, there are feeders dropped from the rails above and tapped into the bus wires within most of the 2-1/4" holes in the HCD.  The bus wires are fished within the HCD to keep most of the wiring from being exposed and hanging down under the layout where it could get snagged.  You can also see the DPDT switch I installed near the command station to cut the power to the entire layout, except for the ex-Southern Ry. interchange in Aberdeen.  This track is now also serving double duty as a programming track.  I no longer will have to remove the entire fleet from the layout when programming.  Yay!  Nothing is worse than accidentally reprogramming the wrong locomotive.

I am using 16 gauge wire for the bus wires, 20 gauge wire for small runs (e.g., between the command station and the terminal block where the bus wires will terminate), and 22 gauge for the feeders.  Yellow wiring is the inner rail, and red wiring is the outer rail (this is a roundy round, you know.)  So far, no shorts, and I only have to drop a handful of feeders in the Aberdeen yard to finish the wiring.

DFF

[svedblen]

Nice work. I like the neat look and how you try to hide most of the wiring.

About your wire gauges: Why is the short run from the command station to the terminal strip 20 gauge wire, while the bus wires are 16 gauge? If you use 16 gauge wire for the buse wires just to keep the voltage drop down then the short 20 gauge run might be OK. But if you use 16 gauge wire to avoid over-heating the wires then you must use the heavier wire between the command station and the terminal strip also. All the current you draw (your total ampere reading) passes there. I would hate to see your layout or property catch fire 

[davefoxx]

Nice work. I like the neat look and how you try to hide most of the wiring.

About your wire gauges: Why is the short run from the command station to the terminal strip 20 gauge wire, while the bus wires are 16 gauge? If you use 16 gauge wire for the buse wires just to keep the voltage drop down then the short 20 gauge run might be OK. But if you use 16 gauge wire to avoid over-heating the wires then you must use the heavier wire between the command station and the terminal strip also. All the current you draw (your total ampere reading) passes there. I would hate to see your layout or property catch fire 

svedblen,

I'd hate to see that, too!  But, I don't think that's a problem here.  I only used 16 gauge as overkill for the bus wires.  After I ran the bus wires, I discovered that 16 gauge wires are too big to fit into the slots in the command station.  So, 20 gauge was the next size down wire that I had.  It's a fairly short run to the terminal block where the bus wires terminate, so I don't think it will hurt anything.  In fact, the layout had been temporarily running on just two 22 gauge feeders for months, until I ran the bus wires and dropped more feeders.

Thanks,
Dave

[DKS]

Given the size of the layout and the total potential load, I'm doubtful there will be any issues with the wire gauges chosen. Short lengths of small-gauge wire can carry a fairly good load; I work on a friend's basement layout that has foot-long 22 gauge drops from the track to the bus, and there has never been any problem with voltage drop or wire heating. If anything, the resistance of NS rail creates a much bigger voltage drop problem.

[Sokramiketes]

Right, ever unwind the wire wrapped around the armature in a motor?  Think how small that guage is.  Small is fine for short runs. 

[JSL]

That's strange that 16 guage wire won't fit in the command as I use 12 guage stranded and it fits in the exact same Digitrax command station.

[davefoxx]

That's strange that 16 guage wire won't fit in the command as I use 12 guage stranded and it fits in the exact same Digitrax command station.

Actually, I could have jammed the 16 gauge wire in there with the screw terminal thingy wide open, but I didn't like how the wire was clamped.  Since the run is short, I just decided to use the 20 gauge wire I had on hand to make it neater.

[svedblen]

OK, given the layout size and the maximum load there will not be any problems in this case. I agree with you all on that.

...I work on a friend's basement layout that has foot-long 22 gauge drops from the track to the bus, and there has never been any problem with voltage drop or wire heating...

But do you not agree that the reason you use less heavy wire for the drops from the bus to the track is not only because they are short, but also because the amount of current in a single drop is less than the current running in the bus. Unless all of your locos happens to be located on the same section of track, fed by the same drop. I always imagined that was also a part of the equation. But maybe I am wrong and this is only a theoretical issue (at least in model railroad applications), not having any impact on your gauge considerations 

 

[DKS]

OK, given the layout size and the maximum load there will not be any problems in this case. I agree with you all on that.

But do you not agree that the reason you use less heavy wire for the drops from the bus to the track is not only because they are short, but also because the amount of current in a single drop is less than the current running in the bus. Unless all of your locos happens to be located on the same section of track, fed by the same drop. I always imagined that was also a part of the equation. But maybe I am wrong and this is only a theoretical issue (at least in model railroad applications), not having any impact on your gauge considerations 

I agree that, given a basement-sized layout, the bus should be robust to handle many locomotives scattered all over the place. Given an HCD with two or perhaps three locos running max, I believe Dave could have wired his whole layout with 18 or possibly even 22 gauge wire with no ill effects whatsoever.

[Chris333]

It all comes down to what did the Seaboard use for their wire? 

[Sokramiketes]

I agree that, given a basement-sized layout, the bus should be robust to handle many locomotives scattered all over the place. Given an HCD with two or perhaps three locos running max, I believe Dave could have wired his whole layout with 18 or possibly even 22 gauge wire with no ill effects whatsoever.

All the bus wire on Modutrak is currently 18 gauge and power is fed from a single location on a 20'x60' loop with no ill effects to date...

[Ian MacMillan]

Mine is all 16ga bus wire, with 24ga drops every 6' to the track blocks and I haven't had a single issue yet.

[mcjaco]

All the bus wire on Modutrak is currently 18 gauge and power is fed from a single location on a 20'x60' loop with no ill effects to date...

Except perhaps the return loops....