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Wiring tortoises, what AWG size do you use?

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Wiring tortoises, what AWG size do you use?
Posted by electrolove on Wednesday, August 17, 2005 3:09 AM
I have learned that AWG 12 stranded wire is good for the track power bus and AWG 18 stranded wire is good for track feeders.

But what AWG size should be used to wire tortoises? I want to wire them like this:

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Posted by Pennsy58 on Wednesday, August 17, 2005 4:00 AM
I wired all of my tortoise machines with telephone wire, which is 24 AWG I believe. I simply bought a 100 roll of the wire at a hardware store, removed the cover and seperated the wires into their colors. That way I had a built in color code for the project.
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Posted by electrolove on Wednesday, August 17, 2005 4:03 AM
Ok, so I don't need more then 24 AWG, thanks. How did you wire them, like my picture?

QUOTE: Originally posted by Pennsy58

I wired all of my tortoise machines with telephone wire, which is 24 AWG I believe. I simply bought a 100 roll of the wire at a hardware store, removed the cover and seperated the wires into their colors. That way I had a built in color code for the project.
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Posted by richhotrain on Wednesday, August 17, 2005 7:17 AM
I use 22 gauge stranded wire. This is available in 33' rolls from Brawa and 100' rolls from Miniatronics. Stranded wire is much more flexible than similarly sized single strand wire and it is easier to work with in my opinion. Resist the temptation to simply twist it onto the Tortoise. Soldering is essential for good connections.

Your wiring diagram is correct!

Alton Junction

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Posted by Anonymous on Wednesday, August 17, 2005 7:25 AM
When I started wiring my tortoise SMM I only had two sizes on hand, so I used the 20 gauge. It's a little big for the job, but works fine.

Trevor[:)]
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Posted by MidlandPacific on Wednesday, August 17, 2005 8:41 AM
I used 22 gauge thermostat wire from Home Depot - copper stuff, it worked very well.
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Posted by howmus on Wednesday, August 17, 2005 8:45 AM
While either stranded or solid wire will work well, I would venture a guess from previous posts that most of us prefer to use solid (no polls please, LOL). Solid is easier to work with in that once it is bent in place, it stays there. It also is easier to solder because you are not haveing to try and keep all those little tiny wires in the right place. A stray wire can cause a short at times. I use both in different places on the layout. It often depends on what I have in stock. Conductivity is virtually the same in either case, and it boils down to personal preference. You are right that #24 wire is plenty big enough for wiring a toroise machine. Always err on the side of too large if you have to make a choice. Your wiring is correct.

Ray Seneca Lake, Ontario, and Western R.R. (S.L.O.&W.) in HO

We'll get there sooner or later! 

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Posted by rrinker on Wednesday, August 17, 2005 8:47 AM
SMALL. I have tons of leftover 8-conductor network cable, so I just use that. I don't need the contacts run back to the panel, so I just zip off the outer insulation (there's a tracer string to do this) and use the individual pairs. It's run wire, not patch cable wire, so it's solid conductor, 24-26 gauge. Telephone wire would work just fine.
A Tortoise only draws a max of about 15ma, so just about ANY wire will work.

--Randy

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Posted by electrolove on Wednesday, August 17, 2005 9:13 AM
So I can't really compare a tortoise with for example a track power bus when it comes to how much it draws? So a AWG 12 or even a AWG 18 is major overkill?

QUOTE: Originally posted by rrinker

SMALL. I have tons of leftover 8-conductor network cable, so I just use that. I don't need the contacts run back to the panel, so I just zip off the outer insulation (there's a tracer string to do this) and use the individual pairs. It's run wire, not patch cable wire, so it's solid conductor, 24-26 gauge. Telephone wire would work just fine.
A Tortoise only draws a max of about 15ma, so just about ANY wire will work.

--Randy
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Posted by selector on Wednesday, August 17, 2005 10:28 AM
Yes, and you may not even get it into the Tortoise. EL, if you have an electronics supply store, even a hardware store nearby, you should be able to pick up rolls of 22 guage wire. Even better, if you knew someone who wires houses for telephones, he/she would slip you a big fat wad of it.
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Posted by rrinker on Wednesday, August 17, 2005 10:58 AM
You might use #18 from the power supply to the control panel, but from each toggle out to the Tortoise, yeah, WAY overkill. #18 will never fit in the hole on the Tortoise.

I'm kind of digging those Tortoise with screw terminals that Empire Northern sells. $2 more but you get 8 easy screw terminals. The stock holes on the Tortoise are staggered for some odd reason, so I assume new holes must be drilled to line up the terminals. Seems more reliable than using an edge card connector, too.

--Randy

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Posted by CP5170 on Wednesday, August 17, 2005 1:24 PM
I used 8-wire telephone wire. I soldered the wire to the Tortoise terminal and then ran the wires to an 8 post terminal strip. I am currently only using the outer contacts but when I am ready to connect to the other contacts, I do not have to disturb the switch machine.

There was an article in Working on the Railroad by Lionel Stang a few years back. That is where i got the idea.

HTH...Ken
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Posted by rexhea on Wednesday, August 17, 2005 2:08 PM
QUOTE: Originally posted by CP5170

I used 8-wire telephone wire. I soldered the wire to the Tortoise terminal and then ran the wires to an 8 post terminal strip. I am currently only using the outer contacts but when I am ready to connect to the other contacts, I do not have to disturb the switch machine.

There was an article in Working on the Railroad by Lionel Stang a few years back. That is where i got the idea.

HTH...Ken


[#ditto]
I also terminate all tortoise points to a terminal strip. To add: I always run a multiple pair cable of 4 pair to this terminal strip from my stationary decoders that are located in a central part of the layout. If the cable is not true telephone cable colors (blue, orange, green, brown, slate, w/white tracer wire) then figure out a color code for terminal 1, then 2, then etc... Stay with this code throughout your layout and it will save on mistakes.

I only hook up those necessary for operating the Tortoise, but I never cut the spare pairs off. Instead, I wrap them around the cable for future use. I use stationary decoders in a central location. If I want to hook up a light in that area, I just pick a pair to connect it to and terminate the other end to the power or control source at the central point. Saves running more wire.[;)]

REX

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Posted by howmus on Wednesday, August 17, 2005 2:52 PM
QUOTE: Originally posted by CP5170

I used 8-wire telephone wire. I soldered the wire to the Tortoise terminal and then ran the wires to an 8 post terminal strip. I am currently only using the outer contacts but when I am ready to connect to the other contacts, I do not have to disturb the switch machine.

HTH...Ken


Kinda like this?

Ray Seneca Lake, Ontario, and Western R.R. (S.L.O.&W.) in HO

We'll get there sooner or later! 

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Posted by tsasala on Thursday, August 18, 2005 11:00 AM
I'd recommend cat-5 networking cable. 8 conductors and you can use easy-to-find connectors throughout your layout. I, however, did not follow my own advice. I recommend soldering the wires to the switch machine and use connectors or terminal blocks near the control panel (not the switch) However, you can put the connectors near the switch. It's your call.

-Tom
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Posted by electrolove on Thursday, August 18, 2005 11:28 AM
To use a cat-5 cable sounds like an terrific idea, thanks. What are the pros and cons by putting the terminal blocks near the switch or control panel? The first thing I'm thinking of is future use of the middle 6 connectors on the tortoise. Can I run into trouble if I place the terminal block at the wrong location?

QUOTE: Originally posted by tsasala

I'd recommend cat-5 networking cable. 8 conductors and you can use easy-to-find connectors throughout your layout. I, however, did not follow my own advice. I recommend soldering the wires to the switch machine and use connectors or terminal blocks near the control panel (not the switch) However, you can put the connectors near the switch. It's your call.

-Tom
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Posted by rtesta on Thursday, August 18, 2005 12:06 PM
Folks, gotta jump in and ask,,,, if i'm going to use my tortoise to switch DCC power on a turnout..

1. do i need to use 18AWG or larger to the machine, if so will i be able to solder wire this big on the connectors on the machine? assume i shouldnt use 24AWG or such here?

2. ive asked in the past, apparently the tortoise internal switches can handle the amps? agree?

i realize i cannot use a 4pdt switch at the control pannel as the tortoise takes time to move, i assume i'd have a short every time, right?

thanks, bt
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Posted by rexhea on Thursday, August 18, 2005 12:41 PM
1. If you have Cat 5 cable on hand or can get it free, then fine. Otherwise, you will be paying a lot of extra money for something you don't need. Cat 5 is designed to prevent "cross-talk" between pairs in high speed data communications...something you don't need to use and pay for.

2. Ordinary telephone cable, that is mostly 24 gauge solid conductor, is all you need to handle the very small current that a tortoise uses and it is a lot cheaper. Some telephone installers will give you hundreds of feet for nothing. Just smile.

3. The wiring advantage to using terminal strips is that you can easily disconnect and change out wiring locations without having to remove components. In other words: You want to change switch 5 to switch number 8. All you have to do is move the wires on the terminal strip and not the switch or component.

4. I like to hard wire (solder) my tortoise with a 12" piece of cable and terminate the other end to a terminal strip, very much like HOWMUS picture. Then I run a main cable back to a central location and terminate the other end to another terminal strip. There I can connect to a decoder, toggle, push-button, or whatever.

5. Again, I recommend not cutting off unused wires. These can be used for future expansion keeping you from having to run more wires/cable.

6. If you are controlling locally, I still recommend the terminal strip between the tortoise and the local control component.

REX
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Posted by johncolley on Thursday, August 18, 2005 12:53 PM
I bought a spool of #20 red and white thermostat wire (almost a lifetime supply) and use it for all my track drops and also power my tortoise machines with 2-terminal blocks. Hint: for crossovers and runarounds, etc. I connect both machines to the same terminal block and use one control for both. No chance of a mishap!
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Posted by rexhea on Thursday, August 18, 2005 1:15 PM
QUOTE: Originally posted by rtesta

Folks, gotta jump in and ask,,,, if i'm going to use my tortoise to switch DCC power on a turnout..

1. do i need to use 18AWG or larger to the machine, if so will i be able to solder wire this big on the connectors on the machine? assume i shouldnt use 24AWG or such here?

2. ive asked in the past, apparently the tortoise internal switches can handle the amps? agree?

i realize i cannot use a 4pdt switch at the control pannel as the tortoise takes time to move, i assume i'd have a short every time, right?

thanks, bt


rtesta,
Routing power on a turnout or powering a frog is the same current/power that you would have going through a track feeder wire. I believe many of us would agree that 22-24 gauge wire is plenty big for both uses.

The aux. contacts on a tortoise can handle 4 amps of current. You will not have a problem powering frogs, signals, and etc.. The "switching rating" at 1 amp that is given in the Tortoise directions only refers to continuous opening and closing like a flashing lamp.

I am not sure I understand your question about a 4pdt switch, but the Tortoise aux. contacts will do the job for power routing.

REX
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Posted by emdgp92 on Thursday, August 18, 2005 1:26 PM
I used 20 gauge wire, as that's what I had on hand. I soldered it to edge connectors. I don't remember who made the connectors, but they work great. I ran the panel lights (a pair of LEDs from Radio Shack off the main power wires. That way, the lights change position when I flip the switch :)

Oh... I should add that my Tortoise machines have their own power supply. I took one of Bachmann's train-set power packs and bolted it to my benchwork.
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Posted by rrinker on Thursday, August 18, 2005 7:21 PM
QUOTE: Originally posted by rtesta

Folks, gotta jump in and ask,,,, if i'm going to use my tortoise to switch DCC power on a turnout..

1. do i need to use 18AWG or larger to the machine, if so will i be able to solder wire this big on the connectors on the machine? assume i shouldnt use 24AWG or such here?

2. ive asked in the past, apparently the tortoise internal switches can handle the amps? agree?

i realize i cannot use a 4pdt switch at the control pannel as the tortoise takes time to move, i assume i'd have a short every time, right?

thanks, bt


I use #20 wire for my feeders - #20 solid DOES fit through the Tortoise hole. #18 I think would be too big. However, using #20 isn;t a problem, we're talking short distances here, and if you are switching the frog, there can never be more than one loco on the frog at a given time. If you are talkign about switching an entire reverse loop, I would run a short length of #20 fromt he Tortoise to a terminal strip nearby, and then use heavier wire for the track feed. A reverse loop should have multiple feeders, the same 3-6 feet as recommended for other track.

--Randy

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Posted by rrinker on Thursday, August 18, 2005 7:23 PM
QUOTE: Originally posted by johncolley

I bought a spool of #20 red and white thermostat wire (almost a lifetime supply) and use it for all my track drops and also power my tortoise machines with 2-terminal blocks. Hint: for crossovers and runarounds, etc. I connect both machines to the same terminal block and use one control for both. No chance of a mishap!


You THINK it's a lifetime supply - sounds like you bought one of the same 500' spools at Home Depot that I did. All I've reall done is make track feeders out of it,and run one line from my converted PC power supply around half the benchwork to feed my one control panel. And I'm at LEAST halfway through the spool - on a 8x12 layout!

--Randy

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Posted by howmus on Thursday, August 18, 2005 7:29 PM
QUOTE: Originally posted by rrinker

I use #20 wire for my feeders - #20 solid DOES fit through the Tortoise hole. #18 I think would be too big.
--Randy


You got my curiosity up so I just went downstairs to check. #18 will not go through the little holes. I used #24 and have no problems powering the frogs with DCC.

Ray Seneca Lake, Ontario, and Western R.R. (S.L.O.&W.) in HO

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Posted by tsasala on Thursday, August 18, 2005 8:25 PM
I also bought the HD spool. For the money, you can't beat it. However, since Cat-5 is so popular, per linear foot, it's cheaper than 2 conductor thermostate wire (2 conductor @ $28/500 feet = 0.028/ft/conductor, 8 conductor @ $78/1000 ft = 0.00975/ft/conductor ).

I will concede you don't need twisted pair, foil insulated conductors for switch machines, but if it's near the same price overall, why not? The question to ask yourself is, will you need all 8 wires, or only two? There is a break even point around 4 conductors.

Personnally, I don't think it matters if the terminal block is at the switch or the control station. However, I would not spend the extra money and terminate at both ends. With all things factored in, an ethernet-like wiring setup for the switch machines will be about the same cost, just as flexible, and take up less space. Those terminal blocks are expensive for what you get.

-Tom
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Posted by grayfox1119 on Thursday, August 18, 2005 9:05 PM
To answer your question regarding size of wire vs current carrying capability, most people use #12 gauge wire for the power bus for the tracks, # 14 gauge for the track feeders from the power bus. #12 gauge wire is rated to carry 20amps, while #14 is rated for 15amps. This is de-rated somewhat, as they are capable of carrying a little more, but all homes are breakered at 20 amps for #12 and 15 amps for #14 wire.
Now for switch motors, all you need to do is look at the specs that come with the motors, they will have the current draw/rating on them. They use "flea" power as we say in the electrical business, only milli-amps (ma) of current. #18 gauge wire can carry 10 amps, which is 10,000 milliamps ( ma). So as you can see, #18 gauge wire is gross overkill. #24 gauge will work just fine.
Dick If you do what you always did, you'll get what you always got!! Learn from the mistakes of others, trust me........you can't live long enough to make all the mistakes yourself, I tried !! Picture album at :http://www.railimages.com/gallery/dickjubinville Picture album at:http://community.webshots.com/user/dickj19 local weather www.weatherlink.com/user/grayfox1119
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Posted by rrinker on Thursday, August 18, 2005 11:28 PM
Those current ratings are for 115VAC too. The main issue with using big wire for DCC is voltage drop, not absolute current carrying capacity. There are charts with the loss in ohms per foot of various wire sizes. The voltage drop is a product of the wire resistence per foot, the length of the wire, and the current being drawn - ie over the same length of wire, running a doubleheader with each loco drawing 1 amp will have 2x the votage drop as the same wire but only a single 1 amp loco running. Now, we're usually talking about a volt or less, with typical run lengths and typical wire sizes. But if you have a run 50' from a booster to a power district and don't use #12 wire, and run more than a couple of locos in that power district, it WILL be enough of a drop to make the trains run noticeably slower.

--Randy

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Posted by rexhea on Friday, August 19, 2005 1:32 AM
QUOTE: Originally posted by tsasala

........... I will concede you don't need twisted pair, foil insulated conductors for switch machines, but if it's near the same price overall, why not? The question to ask yourself is, will you need all 8 wires, or only two? There is a break even point around 4 conductors.

Personnally, I don't think it matters if the terminal block is at the switch or the control station. However, I would not spend the extra money and terminate at both ends. With all things factored in, an ethernet-like wiring setup for the switch machines will be about the same cost, just as flexible, and take up less space. Those terminal blocks are expensive for what you get.

-Tom


Tom, all my mainline tortoise are wired back to Lenz stationary decoders. The reason I chose to use multi-pair cable for my turnout runs, is that I have a large layout and by having spare pairs in place all over the layout gives me the capability to connect future signals, controls, or accessories without having to run new wires/cables. i.e. only short runs of wire from device to spare cable pair. The kind of cable is up to the individual in what he has on hand or prefers to use. Telephone is adequate for the job, but if a person wants individually shielded pairs with ground or fiber optics...what ever works for him.

Over forty years experience in the electronic/electrical fields has taught me never to design or install devices using hard wiring. Plugs , terminal strips, or other intermediate methods of connection is always recommended so that there is an easy disconnect for maintenance or modification. Thus, I use terminal strips at both ends. Some buy the plugs that simply insert on the tortoise connector. Both are good methods.

If you don't think you will ever need to remove the tortoise or other types of devices, then hardwire them in. I have chosen my way because I know that tomorrow will bring new ideas that usually means more bells and whistles to install. (no pun intended [:D] )

REX
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Posted by tsasala on Friday, August 19, 2005 11:18 AM
Good point Rex. Since all my turnouts are relatively easily accessible, I didn't bother with a connector at the turnout. I do have connectors at the control panel though.

-T
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Posted by grayfox1119 on Friday, August 19, 2005 12:23 PM
Here is the data for #12 copper wire: The resistance of this wire is 1.62 ohms per 1000 feet. By doing a quick ratio and proportion calculation, the resistance for 50 feet would be 0.081 ohms. So if your layout had 2 amps being drawn, this would give you a voltage drop caused by the bus wire alone, of .081 X 2A = 0.162Volts dc. Hardly enough to be noticable. But, there may be other factors contributing to lower voltage at the locos. You must take into account all the voltage drops at all the various connections off the power bus, even the soldered connections have resistance. And, what can appear to be a good solder connection can in fact have added resistance. If you want to check this out without actually using locomotives, place a resistive load across the tracks out at about 50 feet from the power source, and check your voltage drop. If you had a perfect bus with no wire resistance, and no solder/t connection resistance, you would only have the voltage drop across the load resistor. We all know that this is not the case however, so what we do read for a drop is the sum of the all voltage drops caused by all the little resistances along the route ( circuit ).
BTW, some real good ideas here in this thread for wiring and connections.
Dick If you do what you always did, you'll get what you always got!! Learn from the mistakes of others, trust me........you can't live long enough to make all the mistakes yourself, I tried !! Picture album at :http://www.railimages.com/gallery/dickjubinville Picture album at:http://community.webshots.com/user/dickj19 local weather www.weatherlink.com/user/grayfox1119

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