A Question about wiring for layout

14 Gauge wire is a standard size regardless of the type of wire. The wire you mention is fine for most loads on model train layouts. The difference comes into play when it is used for building wiring (speaker wire is not suitable for use as building wiring).

Plan accordingly and run several power lines from a common buss point and you should be fine.

This is considered "Class 2" type wire in the National Electrical Code.

30 years experience as a master electrician....

The speaker wire will be fine for your layout. Many folks here have or are using it.

Al so  the jacket on speaker wire has a lower voltage rating about 300 volts. No problem using it for a train layout not in less your going to put over  300 volts to the rails.

Thanks, guys, for the quick responses.  RSJB18, I thought I might find an electrician out there.  Thanks for the definitive and informative answer.  The funny thing is I started my career with an electrical engineering degree, but as my colleagues used to joke with me I was "on the wrong side of the decimal point", microvolts and millivolts.  I greatly appreciate the info.  It will let me save a bit of money, maybe add another switch!  CPBILL, I knew there would be SOME reason for the savings the jacket insulation sounds like a great reason for higher cost.

That's why this forum is so great.  A long time lurker, now finally building something, can benefit from the all of the experience in a great, helpful bunch of people.  Thanks, again.

Ron- good luck with the build. Post some pictures as you go.

Gentlemen,

   As an engineer I tend to over kill my layouts with both high grade Transformers and good 14 Gauge Stranded Copper Wiring, sure the Speaker wire will get the job done, myself I over engineer my layouts, and my DCS signal and my voltage never have a problem.  I like the way good Industrial14 Gauge Stranded Copper wire always gives me a DCS 10 signal thru out my entire Christmas layout.  I started using the good wire with my bigger multi level layout, when DCS 1st came out.  Long ago on some good advise, I built my 1st DCS layout with good industrial 14 Gauge Stranded wire, and have never had a problem with any of my DCS controlled layout,  The Legacy when added to the DCS layout runs thru the TIU to one outside rail, and the oppsite outside rail directly from the Legacy Base, that particular wire running directly from the Legacy Base to the opposite outside rail is only 16 Gauge stranded speaker wire, I have had no problems with the Legacy signal either.

IMO always over engineer your O Gauge DCS/Legacy Layouts.

PCRR/Dave

 I have about 8' of 14awg from transformer to TIU to two MTH terminal blocks. From there it is OGR 16awg to all my 22 blocks with short drops of 18awg. The layout is a U shape 18' by 20' with 10s everywhere. I have about 6' left from the 250' roll from OGR. This includes four long sections of isolated rail. The OGR price is still the same as it was three years ago, too. I'm not insisting it's the absolute right way, but it works for me!

The OGR wire is what I used as well. #14 to TIU and then to terminal blocks and #16 to track from there. Works great, haven't had a DCS error unless I forget to turn on a siding and try to start the engine parked on it. I think it's Belden twisted pair wire, probably closer to the speaker wire, but works great.

Thanks, guys.  I was looking at the OGR wire but it seemed just a little pricey.  As it turns out, I must have planned ahead some time ago for this layout.  While going through some unopened moving boxes I stumbled across several 100' reels of 14 ga standard stranded copper wire.  BONANZA!  Also a couple reels of 16 ga.  These must be ten years old, still in plastic wrap.  Hopefully, this time, they will be put to good use.

Thanks for all the great info and suggestions.

I'll try to post pictures as we go.  Be forewarned this is the first layout I've built since I was a teenager, and that was HO.  We shall see.

Pine Creek Railroad posted:

Gentlemen,

   As an engineer I tend to over kill my layouts with both high grade Transformers and good 14 Gauge Stranded Copper Wiring, sure the Speaker wire will get the job done, myself I over engineer my layouts, and my DCS signal and my voltage never have a problem.  I like the way good Industrial14 Gauge Stranded Copper wire always gives me a DCS 10 signal thru out my entire Christmas layout.  I started using the good wire with my bigger multi level layout, when DCS 1st came out.  Long ago on some good advise, I built my 1st DCS layout with good industrial 14 Gauge Stranded wire, and have never had a problem with any of my DCS controlled layout,  The Legacy when added to the DCS layout runs thru the TIU to one outside rail, and the oppsite outside rail directly from the Legacy Base, that particular wire running directly from the Legacy Base to the opposite outside rail is only 16 Gauge stranded speaker wire, I have had no problems with the Legacy signal either.

IMO always over engineer your O Gauge DCS/Legacy Layouts.

PCRR/Dave

I am not an engineer. What does this mean "good wire" - if it is "stranded "copper"" what is the difference and how does one know it is "good"? Is it the exterior coating? Is it the diameter of each strand? Is the number of strands in said gauge? Is it....I dunno...  

4G-Man posted:

Pine Creek Railroad posted:

Gentlemen,

   As an engineer I tend to over kill my layouts with both high grade Transformers and good 14 Gauge Stranded Copper Wiring, sure the Speaker wire will get the job done, myself I over engineer my layouts, and my DCS signal and my voltage never have a problem.  I like the way good Industrial14 Gauge Stranded Copper wire always gives me a DCS 10 signal thru out my entire Christmas layout.  I started using the good wire with my bigger multi level layout, when DCS 1st came out.  Long ago on some good advise, I built my 1st DCS layout with good industrial 14 Gauge Stranded wire, and have never had a problem with any of my DCS controlled layout,  The Legacy when added to the DCS layout runs thru the TIU to one outside rail, and the oppsite outside rail directly from the Legacy Base, that particular wire running directly from the Legacy Base to the opposite outside rail is only 16 Gauge stranded speaker wire, I have had no problems with the Legacy signal either.

IMO always over engineer your O Gauge DCS/Legacy Layouts.

PCRR/Dave

I am not an engineer. What does this mean "good wire" - if it is "stranded "copper"" what is the difference and how does one know it is "good"? Is it the exterior coating? Is it the diameter of each strand? Is the number of strands in said gauge? Is it....I dunno...  

4G-Man- yes, yes, and yes to all of your questions.

What PCRR/Dave is talking about is to use better grade of wire for a layout. When you move up to these types of wire one of the major differences is insulation type. The diameter of the wire (gauge), is no different, but the insulation and voltage rating is. Stranded building wire goes by several different types, THHN, THHW, THWN, etc. This indicates the insulation type. The voltage rating of these types of wire would typically be 600V while speaker wire would be rated 300V or below. I have used mostly speaker wire on my layout with some 300V rated single conductor as well.  Speaker wire will usually have more fine strands while building wire is usually 19. The finer strands give the wire more surface area and therefore lower resistance for audio and low voltage signals.  Every layout is unique and I am not advocating one over the other.

If you want to combine the best of both then use "S" type cords. This is what extension cords are made of, They go by S, SJ, SJT, etc. Home Depot and Lowes sell this stuff by the foot. Usually in 3 or 4 conductors. Pricey though and you have to strip back the outer jacket to get at the conductors.

I agree with PCRR/Dave- trouble shooting wiring problems after you think you are done is a pain. The better wiring job you do the less chance of problems and back trouble from twisting around under your layout. Test as you go.

Bob

yep, wiring for DCS is no problem for TMCC. The DCS wiring is really a track exercise in creating blocks by isolating the center rail. A 14awg bus and 16awg to the track will work fine.  TMCC asks one requirement - that is the outside rails are both common/neutral/black/U and connected.

A bus with taps or two of the MTH 12 terminal boards should do it.