Wiring a layout for DCC

[grumpy]

 I suggest using trailer wiring wire for the bus wires.  . It is stranded , comes 2,3,4 wire  16 gau. For the leads I use alarm wire , 2 wire 22 gau. . I find that this makes the layout wiring a little more efficient
Don

[pdlethbridge]

Can you tow it behind your car Don?

[grumpy]

I have been known to haul a couple of railway speeders behind my truck . and a couple of times I have 10 or so outboard motors so I guess if I put my mind to it I probably could.
Don

[USNavyChiefRet]

Use the calculator.  .26 volt drop or 2%. ,probably not worth the effort or expense.

Personally, I wouldn't use speaker wire as the insulation may not have adequate temperature rating or abrasion resistance. 

I use only THHN/THWN wire rated at 90 deg C.

Do you use 14 AWG THHN/THWN stranded or solid for bus running the length of the layout and then tap into it with your feeder wires?, then connecting the DCC Power Booster section to the bus with 14 AWG stranded or solid?

Thanks again.

Jim

[Yampa Bob]

I use only stranded wire for the bus, mostly for the flexibility and it works with crimp connectors.  All hardware stores have it in rolls, buy only footage you need.

[USNavyChiefRet]

Sounds good. My local Ace is just down the street from me. That is what I was using but wanted to check and make sure I was good. Thanks again, Bob.

[Yampa Bob]

Anytime Chief.  If you have a local Radio Shack, you might consider Euro type terminal strips.  I use them either as is, or cut them down as needed. Small wires should be tinned before inserting into terminals. For very small wires, I strip off extra insulation, then fold the wire double for needed diameter to fill the hole.

Wherever you need a drop or feeder, cut one or two terminals off the strip.  Cut the bus, insert one end into terminal, continue out the other side with bus, stick the feeder wire into either side of the terminal along with a bus wire.  Add "U" shaped jumpers on input side for multiple terminal outlets.

By using 2 terminals at a location, you can fasten the terminals to the layout with small round head screws, through the provided hole. Terminals are easily cut off with a razor saw.

[Jim Banner]

I agree with Bob about using European Style Terminal Strips, if you are unable to solder the wires.  You may find the 274-680 mini terminals from Radio Shack a bit small for stranded 14 gauge wire as they are designed for 16 gauge.  But give them a try.

I disagree with Bob about tinning the wires.  You have a better chance of a gas tight connection with bare copper.  Besides, if you have a soldering iron and know how to use it, why not go for the very best permanent connection?

[Yampa Bob]

The 274-680 terminals will easily accomodate one 12 gauge wire for a block connection, even 10 gauge by cutting off a few strands before twisting.   It will also accomodate one 14 gauge and one 20 gauge twisted together.  Trust me, I just tried it.

Cutting off a strand or two of the bus doesn't affect the ampacity.  Always twist the strands tightly before inserting into the terminal. If you are inserting two wires, twist them together first as you would for soldering or using a Scotchlok wire nut or crimp terminal.

Tinning the wire is optional but it keeps the strands from spreading and allows subsequent disconnection and reconnection if needed. It also provides a better strain relief for small wires.  I always tin smaller wires in panel work (I edited my post to reflect this) 

I routinely use the Euro terminals for PV combiners up to 10 gauge and never had a problem. Soldering and using heat shrink tubing or tape is fine if you never plan to expand or alter the wiring, but for ease of wiring and convenience, the terminals are hard to beat.   

[Jim Banner]

Bob, I have no problem with some Euro Terminals taking 10 gauge, or even larger wires.  But maybe Radio Shack is selling or has sold more than one size as their part number 274-680. The ones I got from The Source, Canada's present iteration of Radio Shack, are small and seem to correspond to the Radio Shack part number 274-680 that I found at the link below.  However, who knows when their website was last updated or how well the online descriptions match the store package description.

http://tinyurl.com/b96smx    The 274-680 is the fourth one down.

Solder, unsolder, resolder, add more wire, chop off extra wire, its all quick and reliable as long as you use copper wire.  Welding aluminum wires together - now that's tough.

[Yampa Bob]

It is possible our local Radio Shack has the wrong part number for the ones I have. However, I found one site that listed the dimensions for all the Euros, seemed to match mine.  If you have one of the 680, can you give me the overall length of the 12 position and confirm the maximum wire gauge?  Mine measure exactly 3-3/4 inches overall.

Actually, I wish they were made much smaller, say for 20 to 30 gauge, would be very handy to wire decoders in tenders and such.  Perhaps the ones you have would fit my needs.

I've searched for months trying to locate micro terminal blocks, only ones I found are for PCB mounting.  Please check out the dimensions on these and tell me what you think.
http://www.ebyelectro.com/terminal-block-product-info.asp?ProductID=85

BTW, I recently received the 2009 Allied Electronics catalog, 2,272 pages. I can remember when their catalog was just a flier.  I tried Mouser for a time, but have always relied on Allied, and they have a good stock of Keystone products. I really miss the full service electronics stores. Remember "Lafayette" radio stores?

[pdlethbridge]

If you go here, you'll find 7  different euro style terminal strips.
[url]http://www.allelectronics.com/make-a-store/category/755200/Terminal-Strips/Eurostyle/1.html/[url]

[Yampa Bob]

That's odd, none of those match the physical size or capacity of the ones I have. I don't know who makes stuff for Radio Shack, nothing they stock seems to match any standard.

I recently asked the clerk at Radio Shack for a 3mm stereo mini-plug. "Oh we have lots of those", and handed me a 1/4" mono plug.   

[renniks]

    Over here in the UK we call them 'chocolate blocks' as the original version was made from brown bakelite-like substance, way before plastics.  I always have a pack in my tool box altho they are available in most DIY ,electrical and hardware stores.
     Have used 2 x 2way pieces to connect a removable staging board or a lift-out section. Get some brass rod of a size to fit and clamp a 5/8" piece halfway into one hole of each block--then plug them together and add your wires (a cheap polarised connector).

     Eric UK