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Bus Wires

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  • Member since
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Bus Wires
Posted by Little Layout Enthusiest on Friday, February 8, 2013 12:40 PM

I recently saw a short mention of someone using  orange extension cords as bus wires. The wires are already twisted - a good debate whether to always ensues - and it is neat and there is an extra wire included for possible future use. Has anyone had an experience in using the larger extension cords as bus wires? My layout is a 12 feet by 8 feet oval with a double track with sidings and a small yard....it's out of a track book.

 

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Posted by Stevert on Friday, February 8, 2013 1:27 PM

The usual recommendation is to have feeders from the bus to the track every three feet or so.  The jacket on one of those extension cords would make connecting those feeders a lot of work.

Maybe you could use it on on a long run from a booster or circuit breaker to a remote section of the layout, and then use a "conventional" paired bus for that section.

Also, that extra conductor probably won't be of much use on very many layouts.  A pair of conductors might be, but a single conductor - not so much.

So in my opinion, it has more drawbacks than it does advantages, especially on a smaller layout where there isn't a need to span any appreciable distances.

Disclaimer:  There is always a unique situation, or someone who prefers a unique way of doing things, where an extension cord may fit the bill.  But generally speaking, and following the generally accepted methods, again, not so much. 

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Posted by BroadwayLion on Friday, February 8, 2013 1:47 PM

LION assumes that you are cutting the plugs off. It will not do for some visiting monkey to plug them into something.

LION used 14 ga 4 conductor in-wall speaker wire. Him attached it to nails about every 10 feet for access to the circuits.

For REAL BUS WIRES, the LION uses BEAR WIRE, him can solder to it anywhere he pleases. He ties them to nails about every 3' to hold it in place and to prevent shorts. If you are using 14 ga bare wire, you may want to staple the run instead of using nails.

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by Train Modeler on Friday, February 8, 2013 1:59 PM

We have about 300' of track and don't use buss wires.   We do have about 10 zones which are powered from the old block wiring switches.  No power problems.    From our experience then, with good track laying/joining/soldering practices, 30' shouldn't really be a problem. 

Richard

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Posted by Soo Line fan on Friday, February 8, 2013 4:35 PM

One scenario would be to use them going from terminal block to terminal block, other than that it will be more trouble than its worth.

Getting access to the interior wires will be a hassle, especially later if you need to add additional feeders.

Jim

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Posted by betamax on Friday, February 8, 2013 5:25 PM

It would probably be cheaper just to buy wire instead of extension cords and lopping off the ends.  Another benefit is you also know the wire gauge and the colours.  

Plus, it would be easier to route the wires and make connections.

Twisting is another story, as in a small run it would have limited benefit.  

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Posted by eaglescout on Friday, February 8, 2013 6:18 PM

Train Modeler:

I was recently testing my newly laid track with one set of alligator clips attached to an around the room 60 feet of track.  I did not notice any drop in speed around the entire layout as the locomotive chugged along.  Makes me wonder why feeders every 3-10 feet are actually necessary.

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Posted by rrinker on Friday, February 8, 2013 6:45 PM

 12V outdoor lighting wire is probably a better option, just 2 conductors, and heavy gauge.

 

As for lots of feeders, I did the same thing on my previous layout, the initial test before I ran the bus wires was 2 wires from the DCC system to the rails, trains ran fine all the way around the 8x12 layout - and I did NOT solder rail joiners. However, evetually, rail joiners will fail, and the voltage will drop off or end up being interrupted. Better reliable now rather than frustration later when it becomes much harder to install additional drops.

          --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Motley on Friday, February 8, 2013 6:47 PM

Feeders every 3 ft. are even less necessary if you solder your joints.

Michael


CEO-
Mile-HI-Railroad
Prototype: D&RGW Moffat Line 1989

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Posted by Soo Line fan on Friday, February 8, 2013 6:49 PM

Because your newly laid track has new rail joiners. Depending on the care you took during installation, you will eventually notice slow downs. The joiners are basically a double ended terminal. And not a very good one. They have a thin cross section and are easily spread during track laying.

On a DC layout with 2 or 3 engines running together, a voltage drop will be more noticeable than one engine.

I would think on DCC several sound engines would also show a drop before a single non sound unit would.

Jim

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Posted by Texas Zepher on Friday, February 8, 2013 8:06 PM

Stevert
The jacket on one of those extension cords would make connecting those feeders a lot of work.

That was my first thought. Cutting through the jacket is hard and makes it easy to damage the conductors within.

In an almost unrelated thought.  I found that buying extension cords was a lot cheaper than replacing a broken plug on an appliance or other electrical gizmo.

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Posted by dante on Friday, February 8, 2013 9:59 PM

I agree with the negative opinions regarding the use of an extension cord.

Regarding the other comments about the bus, feeders, joiners, etc., I offer the following for what it's worth:

I have an 8'-4" x 11'-6" doughnut layout operated from the doughnut hole.  I have the Zephyr Extra and a second throttle, the UT4R.  I frequently run 2 locos simultaneously, but operating alone, I  do not anticipate operating 3 unless I have another guest for whom I will need an additional throttle.  The Zephyr should be more than adequate even then.

Regarding the wiring, I have a 16awg bus and 22awg feeders connected with the proper size Scotchloks.  Contrary to conventional wisdom, I do not solder all my rail joiners; only on curves. The track and turnouts are Walthers/Shinohara Code 83 and their W/S joiners fit very tightly compared to Atlas joiners.  I also treated the rail ends with No-Ox before joining them.  Neither do I have feeders to every rail section.  There are feeders at the quarter points of the layout and at other locations made necessary because some of my many turnouts are the older, non-DCC variety.  I carefully spotted the feeders on the plan first, tracing the current flow as affected by insulating gaps.  Voltage on the track is uniform throughout the layout.

The layout has been operating successfully for over 7 months.  If eventually any of the joiners do fail to maintain electrical continuity, I can always solder them (without removal).  If the number of feeders I have eventually prove insufficient, I can always add more.

Save yourself extra work until you really have to do more, if ever.

Dante

P.S.  Other important factors:  The layout is in a climate-controlled bedroom; the benchwork and Homabed roadbed are painted to minimize moisture absorption; the maximum temperature variation in the room should not exceed 20-25 degrees.

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Posted by Soo Line fan on Friday, February 8, 2013 10:09 PM

dante
Voltage on the track is uniform throughout the layout.

What method did you use to check the voltage?

Jim

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Posted by mfm37 on Saturday, February 9, 2013 5:35 AM
My NTRAK club usees 12ga extension cords to run power from our boosters to our remotely mounted PM42's. I purchased 100 foot 12/3 cords at the local Lowes for about half the per foot price of SJ cable. I was also looking for a color that would stand out so that members could easily recognize its use. Our cables are bjue because we already were using odange cords for 120 volt AC power. Cut the ends off and the cable into shorter sections. Then installed Anderson Power poles. PM42 needs a ground connection common to the booster so the third wire is required in our case. Extension cords are almost always cheaper then buying wire by the foot. Over the yeas I have found it economical to us an appropriately sized extension cord to replace damaged power tool and appliance.power cords. I wouldn't suggest using it for bus wire unless on a section that had no feeders. To me, stripping the sheathing to attach feeders would not be worth the $$ savings.
Please cut the outlet and socket off if the cable is to be used for any other than 120volt AC. That configuratn of plug and socket are only for house power. Use some of type of plug and socket fr extra low voltage. I once observed a layout using a piece of 12/2 Romex to do the same as our DCC extension cords. That club had used standard two proving outlets and plugs because they were "handy". Imagine if some well meaning member would have pugged that cable into the nesazresst all outlet. 120 vols on the exposed rails. Not good.

Martin Myers
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Posted by betamax on Saturday, February 9, 2013 6:35 AM

Motley

Feeders every 3 ft. are even less necessary if you solder your joints.

There is a point to using a power bus and feeders every 3 to 6 feet.

Nickel Silver, while being a copper alloy, has a lot more resistance than pure copper used in wires.  By running copper wires in parallel with the track, the resistance of the track becomes effectively zero. So you can deliver maximum voltage and current anywhere on the track using the bus and feeders.

This also maintains the voltage at any point within spec, as voltage drop is minimized.

Since some DCC boosters use rate of change to detect a short, additional impedance in the circuit will interfere with that. Again, that is the reason for the bus and feeders.

These are best practices, and named so for that reason.

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Posted by Little Layout Enthusiest on Saturday, February 9, 2013 2:32 PM

Thanks to Stevert, Soo Line Fan, betamax and dante for your responses.  Broadway Lion, Motely and Texas Zepher also offered comments. So the concensus seems to be the method written abouit in many articles of the feeder line every three feet (or so), and the covering on the extension cord being more in the way than a help.

I relate more to dante's layout as mine is also a doughnut, built of five by two foot sections that can be taken apart and moved out of the basement when I retire in a year of so. Thanks to all who responded. It's nice to have the help of more experienced enthusiasts.

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Posted by Phoebe Vet on Saturday, February 9, 2013 2:48 PM

While I don't use extension cords for a bus, I could.  My around the room layout is built in 8 foot segments.  Each segment had a board, hinged at the top, that swings down to work on it.  All my connections are made on that board.  If you examine the photo closely, you will see that the feeders all run off a barrier strip.  The board in the picture has since had a BDL168 added in the space below the strip.  All I had to do was remove that bottom jumper and wire in the BDL168.

Every board has a strip for Track A, one for Track B, and one for Booster Ground.

Dave

Lackawanna Route of the Phoebe Snow

da1
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Posted by da1 on Sunday, February 10, 2013 9:31 AM

Mr. Eaglescout,

It is a misconception that locomotive speed is an accurate indicator for quality DCC wiring.  It is not.

The ONLY test for quality wiring is the short circuit test.  Place a quarter across the rails to cause the booster or short circuit protection to operate.  This test must be successful at every location on your layout.   If the short circuit does not cause your booster to shut down then you need more feeders. 

The purpose of this test is safety, not quality operation.  If a short circuit goes undetected the heat generated will cause local melting of components.  In most cases this will be ties around the rail joints, plastic frogs beside the wheel causing the short or plastic axles on the offending rolling stock.

Finally, using a voltmeter to measure voltage around the layout is not an accurate test either.  The current flowing during these tests is not sufficient to cause significant voltage drop across questionable connections.  Only a short circuit (or dozens of sound locos) will draw enough current to cause measurable voltage across poor connections.

For a more fullsome discussion I highly recommend Allan Gartner's Wiring For DCC.  http://www.wiringfordcc.com

Keep your stick on the ice.
Dwayne A

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Posted by farrellaa on Sunday, February 10, 2013 8:31 PM

Since you don't have much wire to install for a bus, why not just go to Home Depot and buy enough 14 ga red and black insulated stranded wire and do it the right way. It doesn't cost that much and you won't have any trouble connecting feeder wires. I use the 3M suitcase connectors which makes it a simple task to attach the feeders where ever you need them.

    -Bob

Life is what happens while you are making other plans!

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Posted by dante on Sunday, February 10, 2013 10:47 PM

Soo Line fan

dante
Voltage on the track is uniform throughout the layout.

What method did you use to check the voltage?

A multimeter.  I also did the quarter test all around with success.

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Posted by rrinker on Monday, February 11, 2013 6:59 AM

 Tip - use Red and WHITE instead of black - all lit up, it's easy to tell red and black apart, but in the shadows - not so much.

      --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by BroadwayLion on Monday, February 11, 2013 9:36 AM

Black, White, Red and Green ALL have specific uses in the wiring world, and while such codes do not apply to your railroad, LION would choose BLUE and YELLOW, since you are using what would otherwise look like standard electrical wire, and it is not impossible that you might have a 120 volt bus under your layout.

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by Mavryk on Tuesday, February 19, 2013 7:32 AM

Rookie question here....

Does it matter which type of wire I use?  Stranded or solid?

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Posted by rrinker on Tuesday, February 19, 2013 8:07 AM

 Doesn;t matter, but I use stranded for my bus wire because it is easier to pull around under the benchwork, and I use solid for my feeders because it is easier to solder to the rails and poke through holes in the benchwork.

               --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by Soo Line fan on Wednesday, February 20, 2013 9:25 PM

Applications such as automotive will never use solid wire. Stranded is used because it resists vibration better. Also ease of manufacturing and serviceability, its is easier to route wire around obstacles. I cannot comment on marine, aviation or aeronautics but I would think it is the same.

Solid is used in home and applications where little or no flexibility is needed. Also where no vibrations are present. Solid is easier to wrap around a screw terminal and easier to shove thought a hole or series of holes, such as wall studs.

For MR, either will work.

Jim

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Posted by mfm37 on Wednesday, February 20, 2013 9:49 PM

NEC specifies AC wire colors white and grey as neutrals. Bare, green, or green-yellow as ground. Any other color may be used as power because they are not spec'd. Convention is to use black as the first hot and red as a second hot.

They don't cover extra low voltage DCC wiring so pick something that makes sense. and are readily available.  I use red and black because it matches the NMRA color code for track power conductors on decoders. Red and white also makes sense because I also use 2 conductor thermostat wire for feeders. Two conductor T/stat  cable is red and white. I connect red to red bus and white to black bus.Choose other colors for wiring that is other then track power. e.g. layout lighting, switches, accessories.

Martin Myers

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