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Hi All.   As I understand it, from watching YouTube videos on DCC, the bus must be heavy duty, but the droppers from the rails are a lot thinner(please excuse my poor terminology). And I , (like a lot of other modellers) am using Peco Electrofrog points, but I noticed how "thin and fragile" the frog wire is, I appreciate that there must be a good reason for this, and if that wire is so thin then the wire(in my case is connected to a DPDT slide switch) connecting it to the point motor can be as thin. My question is "Why such a variation ? Three different gauges of wire, all carrying the same? current.     all the best. Kevin

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Hi Kevin

Think of it like water pipes.

The mains are much bigger in diameter than the pipes in your bathroom.

The bus is carrying the current for the whole layout, while the wires in the frog are only supplying those wheels which are on the frog.

The more water flowing in the mains, the larger diameter pipe you need to get all of the water through for everyone.

The more current you have, the larger the diameter of the wire you need to keep the resistance low.

Cheers

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Hi Max.   Thank you for your reply, it sounds so simple when you put it like that.   all the best. Kevin

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MaxSouthOz wrote: Hi Kevin

Think of it like water pipes.

The mains are much bigger in diameter than the pipes in your bathroom.

The bus is carrying the current for the whole layout, while the wires in the frog are only supplying those wheels which are on the frog.

The more water flowing in the mains, the larger diameter pipe you need to get all of the water through for everyone.

The more current you have, the larger the diameter of the wire you need to keep the resistance low.

Cheers

That's a great description Max :thumbs

Tony.

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Thanks, guys.  :cool:

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Will the water leak out if I cut the insulation .........................?  :cheers :cheers

Great analogy Max.  Most people (me included) can understand water but fail on electricity - probably because you can see water rather than just having to imagine it ............ :roll: :roll:

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Hi Kevin,

Nice analogy from Max.

It all depends on the current draw at the point of operation.That thin wire to the frog is 25 gauge wire (I measured the one on a Peco Code 83), it's good for at least 0.45A (0.457A for pure copper) and more realistically somewhere approaching 3.5A.The current draw on a large OO engine running across the frog is probably 0.2-0.5A. And that is not continuous, so heating of the wire is not an issue.



Nigel


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BCDR wrote: Hi Kevin,

Nice analogy from Max.

It all depends on the current draw at the point of operation.That thin wire to the frog is 25 gauge wire (I measured the one on a Peco Code 83), it's good for at least 0.45A (0.457A for pure copper) and more realistically somewhere approaching 3.5A.The current draw on a large OO engine running across the frog is probably 0.2-0.5A. And that is not continuous, so heating of the wire is not an issue.



Nigel



Nigel, is what you said correct ?  frog wire good for 0.45A and more realistically approaching 3.5A

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Hi Nigel. Thank you for your reply , that explains a lot. But why is such an important piece of wire so fragile?Maybe it is a "ruse" to sell more sets of points , I have three sets that I needed to repair after changing my plan.
all the best. Kevin

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Hi Ron.   Everyone is getting very technical today, is that milliamperes or what? it is all Chinese to me.The" Black Art" of DCC strikes again??    all the best. Kevin

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Kevin 0.45A = 450 milliamps DC , AC or DCC - it is all the same

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Hi Ron,

That's what the tables say. 

http://www.powerstream.com/Wire_Size.htm

24 gauge, 3.5amp for chassis wiring, 0.577amp for power transmission. Somewhere in this range will be the reality.

This is for soft copper wire. Multicores have lower capacity.

http://www.engineeringtoolbox.com/wire-gauges-d_419.html

And of course:

https://wiki.xtronics.com/index.php/Wire-Gauge_Ampacity

Nigel

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Hi Kevin,

If the original wires put there by Peco have come adrift from the underside of the frog, and you're worried about replacing with gauge 24 wire (as you know I use 24 gauge tinned wire ready for soldering),just replace with 22 gauge wire (or whatever wire you're using for the rail droppers). That will give you 0.92amp. Anything bigger than 22 gauge (20 for example) is getting a bit big, unless you start hacking the plastic around the existing access hole to the frog underside. Of course you can just hold the tip of the iron in the hole - the diameter will increase dramatically.

Nigel

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Thanks Nigel, learning new things each day,

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Hi Ron.  Thank you, I was thinking that when the Telecom engineers are working around junction boxes they leave behind lengths of fine wire, which until now I have been collecting for scenic effects( trunking etc ) but that wire is very similar to the frog wire. Could that wire be good be good enough to extend the frog wire the two or more feet to the DPDT slide switches that I use for point control?? I could have a fire extinguisher handy just in case:lol::lol::lol:LOLall the best. Kevin

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Hi Nigel.  Thank you. I am a complete "Bodger", alas there is no "Finesse" with my work. I have been bullying regular wire into the underside of the frog and soldering, hoping for the best, one idea I came up with, terminal blocks under the baseboard , for the junction between the two wires, which I hope would make things easier. all the best. Kevin

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Passed Driver wrote: Hi Ron.  Thank you, I was thinking that when the Telecom engineers are working around junction boxes they leave behind lengths of fine wire, which until now I have been collecting for scenic effects( trunking etc ) but that wire is very similar to the frog wire. Could that wire be good be good enough to extend the frog wire the two or more feet to the DPDT slide switches that I use for point control??

YES

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Hi Kevin,

Terminal/barrier blocks? Yes, it's a good idea for several reasons. No splicing of the power bus, easy to move dropper leads around (track and DPDT switches), if you use 6-8 terminal ones you can add a DC bus and still have 4-8 terminals for droppers. Run a 240v circuit and have a socket for the kettle. Label the wires.I use 30amp double row blocks that take 10-22 gauge wire.

Mount them 3-4 inches from the end of the module to the underside of the top. It's a good idea to standardize on the length of the droppers, that way resistance and voltage drop is constant. If you mount them parallel to the sides of the module rather than parallel with the ends it's a lot easier poking wires into the terminals, and you can have them flush to the ends. There is no reason why they have to be parallel to the ends. I use Powerpoles from the terminals to connect modules.

Get the big ones as you will have several leads connected to the same terminals (power bus in/power bus out, dropper(s) out, and if necessary daisy-chain smaller ones off the big ones (power bus out, power bus to dropper block out).

Nigel


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Hi Nigel.  Thank you for your reply. I had only thought about using terminal blocks for the frog wires. But with a stretch of the imagination ? The possibilities are endless.   all the best. Kevin

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Sol wrote: Passed Driver wrote: Hi Ron.  Thank you, I was thinking that when the Telecom engineers are working around junction boxes they leave behind lengths of fine wire, which until now I have been collecting for scenic effects( trunking etc ) but that wire is very similar to the frog wire. Could that wire be good be good enough to extend the frog wire the two or more feet to the DPDT slide switches that I use for point control??

YES

Hi Ron and Kevin,

MAYBE. This is a "devil in the detail" one. Telephone wire is either 22 or 24 gauge, :thumbs :thumbs :thumbs,telecommunication wire such as RJ12 (computers, your layout, etc.) is 28 gauge and is only intended for low voltage/low current applications such as sending signals. AWG says 1.4 amp chassis wiring, 0.23 amp power line. Hmm. Borderline at best. Ethernet cable (Cat5 for example) is 24 gauge (and a lot of it) :thumbs :thumbs. If Ethernet cable or telephone cable is going for free, it can be re-purposed. You get some funny colors though with and without stripes. Use labels attached to each wire JIC, because 6-months down the road and you will be having an "oh dear" moment or three.

You can get spools of 22 or 24 gauge wire for a couple of groats. And zero time getting it out of a multiwire cable and deciding which shade of puce to use next.

Nigel
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Hi Nigel.  Thank you, so making a general rule "blindly"? Without knowing the gauge of the wire could drop one into deep water. And at least if one purchases it from a reliable source it shoul be okay? But (not eBay?). But where? because the power poles that I purchased on the eBay site really look lightweight., Maybe I was expecting too much?all the best  Kevin

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I use it all the time and for the last 55yrs for everything except bus wire,never had a prob in all that time
:thumbs ;-) :cool:
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Hi Owen.  Thank you for your reply. When you say " You use it all the time and for the last 55 years", what part of the thread is it?? 22 gauge wire, 24 gauge wire , odd unknown lengths of Telecom wire or what?:???::???::???:.all the best Kevin

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Hi Kevin,

Telephone wire is fine. Some of the very thin wire used in modern communication devices (USB or JST cables for example) is meant for low current. Using thin low capacity wire is fine until the day a locomotive derails on the frog, shorts it out and full track amperage goes through it. OK with 1.7 amps, not so good with 15 or 20 amps. Bit like putting a screwdriver across the ends of a live socket, interesting things can happen.  I believe you have an NCE Powercab system, there is a reason why there are 2 different cables ("telephone" and coiled). One for power, the other for when the unit is used as a dedicated controller.

I was just reading an article where a Soundtraxx Soundcar decoder (cattle, clickity-click, etc.) was connected to wheel pick-ups in a freight car. The wire used was 30 gauge, which is fine because a sound only decoder doesn't draw that much current (primarily to drive the speaker, 15-20 mAmp) and the risk of shorting out is minimal.

Owen is right, you can use pretty thin wire as long as everything else is OK and you have control over the load they will carry. I take a more cautious approach and if possible go up (down actually) a gauge. You get the benefit of decreased resistance as well. 24 gauge copper is 25.7 milliOhm/foot, 28 gauge is 65, 30 gauge is 103. This translates into heat. Not that important for a frog, which may have current flowing for 1-2 seconds at a time, but droppers (depending on how frequent you have them) could be passing current much longer than this. Wiring does get hot, and this is when the type of insulation used gets important.

This the reason why club set-ups tend to be cautious electrically ,and are wired to minimize resistance and voltage drops and have wiring standards. Careful attention is also paid to how many engines will run at anyone time and what amperage will be required.

Nigel

Edit: There is plenty of information on wire gauge and wiring available. In general, 12-14 gauge for the power bus, 20-22 for the rail droppers, down to 24-30 for things like frogs and sound decoders, lights, speakers, etc. I have a GWR Castle with working oil lamps, they are wired directly to the track pick-ups with 30 gauge enameled armature wire (plus an appropriate resister, these are surface-mount LED's). Horses for courses really. 

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Hi Nigel. Thank you for your reply on electrickery. I don't know much about the gauge size of wire that I am using, but,when I resumed the hobby I referred to the forum, and followed the advice there on. At first there was advice about purchasing coils so wire on eBay which I was not completely satisfied with, then I found a "Thread by Max" about stripping 2.5 mm 240 volt cable(twin and earth) for the DCC bus wires, which I did. The droppers quote "I use multi strand cable" unquote.  So I set off to the local electrical dealers and purchased 10 metres of the cable that he had used, but for the droppers, I used regular lighting "multi core" again stripped, the only difference being "Red and Black" in the 2.5mm , and "Brown and Blue" in the multi strand. The Brown and Blue multi strand being the wire of choice for connecting the frog terminal block to the DPDT slide switch centre contact.
The only reason that I mentioned the Telecom cable was "it was of a similar appearance to the frog wire". 
That I will keep for scenery.    all the best. Kevin

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Hi Kevin

Can you point me to the thread, please?  I think I must have made a mistake.

The droppers are multi-strand, but 1.0 mm.

Cheers

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telephone wire which I was told carried 50vlt at 10amp also alarm cable slightly finer but 5 amp which I use for my street lights
:thumbs ;-) :cool:
Owen

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Hi Max.  At the time? I photocopied the "under baseboard layout and your description of the very neat job". I do have a copy of it on file, but I don't know how to find the thread, otherwise I would point you in the correct direction .Wish I could help you, all the best. Kevin

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BCDR wrote: . Bit like putting a screwdriver across the ends of a live socket, interesting things can happen.

Not in DCC of course, all that will happen is power goes off (layout or block, depends on the wiring). :roll:

Nigel

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Silver Fox wrote: telephone wire which I was told carried 50vlt at 10amp also alarm cable slightly finer but 5 amp which I use for my street lights
:thumbs ;-) :cool:
Owen
 
Hi Owen,

The following is from Superior Essex, a telecom company:

Voltage and Current Limits for Telephone Wire and Cable Based
on Telephone Operating Company Experience

Maximum Voltage (dc)              Maximum Current

Pair-to-Ground     Pair-to-Pair   (Amps)
150                       300               0.15

Nigel
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well you live and learn,my info came from a BT engineer too,still nice to know  thanks
:thumbs ;-) :cool:
Owen

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Hi Owen and Kevin,

Tin cans and string never had these issues.

I suspect most of us are are the mercy of those who (may) know better.Then again...volts, amps and ohms are the fundamentals, I try and get my head around them (and err on the side of caution when wiring). We all tend to ignore the other parameter, watts. All those electrons zipping around encounter resistance, and generate heat. Stranded steel wire is a lot cheaper than solid or stranded copper, but does have a higher resistance (40-times more).

One analogy that may be useful is the high density foam cutter. This uses 12-24v, 2-5 amp, 30-ish gauge stainless steel wire, and gets very hot.  Which then of course makes me wonder about local heating of wires in close proximity to foam baseboards. 12 gauge copper bus wires don't have much resistance, 24 gauge droppers however have 16-times more resistance.

Nigel

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Hi Nigel.   Thank you , but all these facts are going over my head? although very important, I am pleased to say that I have chosen a Plywood Baseboard. Suffice to say, when my Triang TT 0-6-0 tank model ran round in circles powered by two 6 volt batteries, things were so simple. But back to the 21 st century, when I was using "Vista" or latterly Windows 8, I was able to scan and email a document but "Windows 10 has got the better of me! (before you ask where is this going or this isn't in the script??).I am referring to my "Twin and Earth Cable" message. Created by Max, he had ask me to point him towards it on the forum, but even though I scanned it at the time, I am flummoxed, otherwise I would scan it and email it to Max.
all the best. Kevin

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Hi Kevin,

Basic electrickery is something I believe railway modelers need to understand (even if it's only the relationship between volts, amps and ohms) once the move from train set to model railway is made. It has a direct impact on layout wiring, electric motors and the DCC decoder capacity, especially if you start putting in decoders yourself.

However, If you stick with 12-14 gauge for the bus, 20-24 gauge for the droppers and 24 gauge for the frogs it will work fine. Your NCE Powercab is putting out 2 amp max, and that is the worst case scenario your wires will ever have to handle. With one modern engine 0.5 amp is the most those wires will carry, half that if you are puttering around shunting.

If you have a look at the wiring in an old Triang or Hornby those wires were big by today's standards, motors were inefficient, and all those sparks and burning smells added to the fun. Rail droppers? :lol: :lol: :lol:We all made do with fish-plates. It's all a bit more precise with DCC, and should we be inclined we can calculate what wire gauge is going to be appropriate. I just use a tried and tested set of standards.

Some of these issues are important, some are interesting to understand. Some are downright incomprehensible.

I came across this great online tool  for calculating wire gauge from voltage and amps. It's for DC, but should be the same for DCC. See http://www.solar-wind.co.uk/cable-sizing-DC-cables.html

Couple of examples that I plugged in with a 1% loss in current:

15v
2 amp
4 meters (medium layout, bus)

Wire gauge = 13

15v
5 amp
10 meters (large layout, bus)

Wire gauge = 5

15v
0.5 amp
0.25 meters (DPDT to frog)

Wire gauge = 26

24 gauge is therefore quite adequate for the frog feed, and gives over-capacity (which is always better than under). Increase the length to 0.5 meters however and 22 gauge wire is needed.

For a dropper wire 2 amp capacity and 1 meter long 19 gauge is needed, for 0.25 meters long it goes to 26 gauge.

Longer wire always means greater resistance, which requires a bigger wire. Which means keeping droppers and frog wires as short as possible.

Nigel

P.S. I use Windows 7, which I note still gets regular updates and fixes. Which means it wasn't ready for real-time when released. Having watched my wife succumb to Windows 10 and then spend the next month getting things back to what they were I'll stick with 7, as 10 is probably getting updates and fixes. The day MS stops supporting 7 is the day I'll switch to something else.



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There has always been a slight problem with wire/cable sizes this side of the pond. :roll:

The UK, always wanting to be just slightly different from the "others", although in fact, I think the whole of Europe, uses wire diameters in "everyday" use, not gauges.  We refer to a wire being 0.2mm or, in the case of domestic house wiring, 1.0mm, 1.5mm, 2.5mm, 4mm and so on.

I always have to look up "our" equivalent to a gauge size ..............................plus, gauges are not "logical" in that the thicker the wire, the smaller the gauge.  :???: :???: :???:

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Hi Peter.    Thank you, or should that be merci ? I never got beyond "schoolboy French". But in my humble opinion it was a mistake to get involved with Europe , but once we did ,I believe that it was Europe that should have toed the line, never mind metrification or decimalisation. The UK had already tried that,with the "Florin", the old two bob, and decided that it was better with  pounds, shillings and pence . At least we still have proper "three pin plugs" it was a pity that the colours of the wire had been messed with . Stick with what you know! That is why I only know franglais ?"Vive La Difference". Sorry for my difference of opinion?  all the best "Bon Chance"?   Kevin

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Something I typed up ages ago from various sources.

Bit approximate, but may be of use as a rough guide.





Ed

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Hi Ed.  Thank you, with all this useful information flying about, I had better study how to "fax and scan" on my Windows 10. I don't know why I went for 10, Windows 8 was much easier. all the best. Kevin

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Hmmm, Windows 10. Brave man Kevin and definitely a case of bon courage rather than bon chance!

Hope the day treats you well,

Bill :)

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Hi Bill.  Thank you, Too true, but when I kept getting bombarded with messages I eventually capitulated? What a wallyall the best. Kevin

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Ed wrote: Something I typed up ages ago from various sources.

Bit approximate, but may be of use as a rough guide.





Ed

Hi Ed,

Useful information, seems to be on the "chassis" wiring side rather than "power line" side. Especially 17 gauge for 6-10 amps for bus wiring, which should probably be considered as power line wiring as it could conceivably carry something near that load under the right circumstances (big layout with lots of engines running at the same time). I know my first layout with DCC used 18 gauge wire for the bus (it was to hand) and never had any problems. Only one engine at a time though.

Nigel

Chassis load is usually less than the power line. 

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I use 7/0.2 for my droppers (I think :roll:) so that table just shows how necessary it is to have a dropper for each piece of track.  If not, one could soon run up a fair old demand if running several locos with sound and lights, plus some lit coaches with a dropper only every 3 or 4 yards - particularly if a few of those trains happened to end up on the same "feed block" ...................... :shock:

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Hi PeterMac,

7/0.2. 7 cores of 0.2mm diameter. Somewhere between 23 and 24 gauge equivalent. Spot on for a 2 amp DCC set-up with modern engines and code 100 track.

Nigel

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Hi Kevin
 I found this copy of a book on the net some time ago .
 although it goes deeper into electronics  than you will
 ever need to go , I have always found it handy to have around .
 There is a free download if you want .
The title is Electronics For Model Railways .  Just type the name
 in the google search box .
 Regards Ted
 

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Hi Ted.   Thank you for your reply, I will have to download that and see where I go from there. All the best. Kevin

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just to say what 12vlt can do I recently had an incident on my set-up where a fish plate / joiner became glowing red hot because of poor conductivity, code 100 rail and 4amp supply, lucky I was in there at the time
:thumbs ;-) :cool:
Owen

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... and I've just fried a Peco solenoid point motor by not taking the time to check my wiring... at least I think I have... it was hot, had that burning electric smell and now won't work! 
Kevin, 
I was a complete novice with electronics and wiring when I first started 10 years ago, I took the time to try and learn as much about electronics as I could and have really enjoyed the process. I now know enough to be dangerous!

Enjoy

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Hi Marty.   My first Hornby OO railway I kept away from their point motors, and went for Hammant and Morgan , my local " toy shop " sold all types of railway models including "German. Railways" well he was a German , after allAnd I purchased some German made passing contact switches that worked a treat. Not really for me ?? but I have been recommended to buy."Tortoise Switch Machines" as The easiest to wire , and the most reliable.
all the best. Kevin

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Hi Kevin,

The Tortoise switch machine is DC. For DCC operation you need the SMAIL which has a built-in DCC decoder or a third-party DCC decoder such as the "Hare" that will supply the DC current (12v, 16 mAmp). It's easier (and cheaper) to have a 500 mAmp 12v transformer and a separate DC circuit.

Nigel

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Hi Owen.   Something has got to change? If you are confident that it wasn't your workmanship then maybe you had a bad length of wire. Personally I'm no expert but I have read about "Flux" deteriating the joint and causing such a problem , if you use "Flux" for flux sake don't forget to clean up after you. What about additional smoke detectors? all the best. Kevin

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Ted wrote: Hi Kevin
 I found this copy of a book on the net some time ago .
 although it goes deeper into electronics  than you will
 ever need to go , I have always found it handy to have around .
 There is a free download if you want .
The title is Electronics For Model Railways .  Just type the name
 in the google search box .
 Regards Ted
 
Hi Ted,

The Circuitron booklet? If so it doesn't touch track wiring. Nice reference booklet though.

Nigel

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Hi Nigel.   Thank you , maybe the person that recommended them to me, didn't realise that I was using DCC?If? and before I make such a recommendation again I better be careful, for instance is the job straight forward? And does it cos much?   All the best. Kevin

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Hi Kevin,

A separate DC circuit is required for Tortoises (and Cobalts). A 12V 2A transformer will set you back £3.50-£4.50. Enough for 80-100 all motors at once. SPDT switches are less than £1.00 each.

Decoder control is going to be at least an additional £10.00 per turnout, and depending on which one may still require a dedicated DC circuit. If the decoder uses DCC bus power it's advisable to use a separate booster circuit for the turnouts  that is isolated from the running tracks. Which probably means upgrading the system with a booster. Just in case...

You can change frog polarity and activate signals from the stall motors (for the Tortoise there are 2 SPDT switches with 4A capacity each, same for the Cobalt I believe), which will effectively give you interlocking. With the Tortoise you can also control a signal and crossing gate mechanically with the "Remote Signal Activator", which is a wire-in-tube fulcrum system.

Of course mechanical WIT mechanisms and kits are available with 1 or 2 SPDT switches if you want to forget about the electrickery and keep it purely mechanical (for example Blue Point switch machine, Fast Tracks "Bull Frog"). Which of course appeals to the Luddite in me (and keeps the amount of wiring down). I fancy the "Bull Frog" kit for the crossover I recently built. $22.00 for the mechanisms, SPDT switches and WIT in components, no DC circuit, no decoders, and I have frog polarity changing built-in. That's for the club modules, I'll probably go with Tortoises for home (US made so no import duty, 9 years warranty).

Ah, the tyranny of choice!

Nigel

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Hi Nigel.    Thank you, now you can see why I prefer the (sometimes?) straight forward WITall the best.  Kevin

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Also look at Cobalt motors, Kevin.

Much smaller than the Tortoise and equally as good.

I've tried them both.

https://www.dccconcepts.com/product-category/the-cobalt-collection/

My final choice - servos.

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Hi Max.  Thank you, but don't get me wrong? As I was replying to Marty's  thread. DCC wiring can be complicated enough without adding more bundles of wire. Some undersides of baseboards tend to look more like Medical Teaching Mannequins?      all the best. Kevin

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[color="#0000dd" abp="479"]BCDR wrote: Hi Kevin,

The Tortoise switch machine is DC. For DCC operation you need the SMAIL which has a built-in DCC decoder or a third-party DCC decoder such as the "Hare" that will supply the DC current (12v, 16 mAmp). It's easier (and cheaper) to have a 500 mAmp 12v transformer and a separate DC circuit.

Nigel

For DCC operation the best accessory decoder for Tortoises is the NCE Switch 8 (MK2 version).  This has 8 ports and each can operate a pair of motors for crossovers - I have one that has 15 Tortoises connected. They cost around $60 in the US, around £40 in the UK.  They also have an optional input from a 9-12v DCC transformer if you do not want them to use DCC bus power.

I have mine on a separate DCC bus with its own booster so that turnouts can still be operated if the main track bus has suffered a short circuit due to derailment, wrong point setting etc.

Last edited on Sat Oct 29th, 2016 02:52 am by RFS

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Hi  Nigel
 In your reply regarding point motors you state that cobalt motors need a
 separate DC supply .  Cobalt point motors will operate on both a  DCC & DC supply.
 I have several cobalt motors wired directly to the DCC supply with a small resister to
 reduce the voltage to approx. 10v. They are probably the easiest decoder to program
 The inbuilt decoder has an aux switch ,which can be used to operate other accs.
 :)
  Regards Ted

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Hi Robert,

I didn't mention it as it's hijacking Kevin's thread. Around $54 or less for the Switch-8 Mk2, which works out at around $6.50 per motor, $3.25 if you double up the Tortoise. Add the button board to keep the wiring sane.

I'm in the fortunate position of having to deal with relatively few turnouts, either at home or on the modules. Most club members have ground throw levers with SPDT switches built-in (Caboose Industries) which change the frog polarity, $4.79 each. No decoders, minimal wiring, no DC circuit.Getting fingers in-between a couple of trains to throw the switch gets interesting, hence my interest in the even more hands-on approach of Blue Points and Bull Frogs.

Like Max I've tried Tortoises and Blue Cobalts (and Peco solenoids, got a bag full of them somewhere). Unlike Max I lean towards Tortoises. Both get the job done. Tortoises are $1.30 cheaper than a Cobalt Classic from my favorite box-shifter.

Nigel




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Hi Nigel.    What or Who is a box shifter?     all the best. Kevin

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[color="#008833" abp="479"]Passed Driver wrote: Hi Nigel.    What or Who is a box shifter?     all the best. Kevin

In the UK the likes of Hatton's, Model Railways Direct, Rails of Sheffield etc.

Last edited on Sat Oct 29th, 2016 01:46 pm by RFS

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A "box shifter" is a discount volume seller Kevin - mainly online.  Normally, they don't bother much about the "finer" things to do with model railways but are price cutters for RTR items - usually coming in "boxes", locos, rolling stock etc. etc. and rely on "shifting" a high volume at low margins - hence "box shifters".

I'll bet they sell 50 locos for every one sold by your local high streeet model shop and nowadays, they do seem to be getting much better at offering other, smaller/cheaper, items and advice.

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Hi Petermac.    Thank you for your reply. Sounds like the "Tesco Founder" , "Stack them high Sell them Cheap".and it worked for him, okay.   all the best. Kevin

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Petermac wrote:
 your local high street model shop 

What's one of them, do they still exist anywhere outside big cities  quest:  :sad:  :sad:

Ed

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Hi Ed.   Too true , I remember when ( I'm really showing my age now) there were so many shops within walking distance from either home or work, you would have thought that they would always be there. I don't mean "Just Toyshops" either. Near Charing Cross you had Hamblimgs, and Allan Brett Cannon at London Bridge, not forgetting Kings Cross models, and many many more.  all the best. Kevin

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Hi All,
I hope I made not a mistake, replying to an over 2 years  or nearly 3 years old thread, but the questions and maybe Infos I have handling about this topic and to open a new topic would be not a well idea?

Well I did in 1995 a two year electronical retraining course but without end exam. So I learnd some useful and helpful things about electricity and electronics as base Knowledge.

Here in central europe specially in germany our public electricity net changed the AC Voltage from 220 V AC within one decade into EU Standards of 230 V AC.
before 1996: 
220 V ~ AC +/-  5 V by 50 Hz
from 1996 to 2006:
230 V ~ AC + 5 V/- 10 V by 50 Hz
since 2006:
230 V ~ AC +/- 10 V by 50 Hz
Older AC equipment is allowed to used by own risk.

Telephone Copper wire have got two pairs of drilled wire blank GND wire which is drilled together into the bigger cable. Each of the four wires have solid cores of 0,24 square mm.
The Telekom is using 60 V = DC for speaking and 60 V ~ AC for ringing.
For using as DC or DCC bus wire, the double drilled cables can making problems.

Much better are undrilled cables or flexible wires.

The modern Standards for house electrics are NYM cables with solid cores: Phase 1 (brown), 0 (blue) and Ground (yellow-green) of 1,5 square mm. Allowed fuses are up to 16 A.
At some old northern german houses, the "Short 0" is sometimes allowed by not lighting floors like wooden floors, than sometimes the GND wire is not existing or anywhere connected with the 0 blue wire.
In such causes it can happen that electric stuff with metal surfaces have the full current against earth of 230 V ~ AC onto it. There will be a danger of an Accident when using longer wires inside household to rooms with stone floors or rooms with water supplies.

Solid Core copper cables or flexible multi core copper wires:
(0,5 sq mm in diameter - fuse of 3 A)
0,75 sq mm - fuse of 6 A.
1 sq mm - fuse of 10 A.
1,5 sq mm - neozed fuse of 13 A, old 16 A.
2 sq mm - fuse of 16 A.
2,5 sq mm - fuse of 25 A.

For layout or module bus wiring,
1 sq mm to 1,5 sq mm works best on cheap prices. More expensive is the 2,5 sq mm wire. 

Connections of in minimum all 50 cm to the tracks can be done with 0,5 sq mm wires.

Very often will be forgotten the to do the connection between power pack or DCC Central Unit...it is important to do it with the same diameter of the bus of under the layout or modules.

In central europe most DCC Central units have 3 A, shortly 3,5 A.
Bigger DCC Units using 5 A.

For wiring of model railway equipment the most manufacturers using the 0,12 sq mm or 0,24 sq mm wires...these are in most causes too thin at all.

What kind of cable or wire diameters are you sing for your layout or modules?

Me I am using as Standard 1,5 sq mm solid core copper cables forthe module bus and connecting all 50 cm with 0,5 sq mm to the tracks.
Will this work well?

For Switching electrics I use where needed 16 V ~ AC.
My plan is to remove the Interlocking Electrics and changing it into a lever and piano cord system to do the interlocking manually.
I use DCC for driving trains only.

BCDR
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Hi Ingo,

I follow NMRA recommended practices for DCC wiring. These are described using AWG (American Wire Gauge) sizes. Difficult to make a direct comparison with European wiring, usually described in mm2. Which refers to the area of copper, not the diameter. Most modelers use copper wiring, either solid or stranded. Good conductivity and low resistance, and easy to solder. Modern motors mean that the high amperage seen with old stock is not an issue.

12-14 gauge wiring is usually sufficient for the bus on a short to medium size layout. I use 14 gauge solid copper as it is easier to work with than 12 gauge. What this corresponds to in IEC 62208 is not exact. For example 14 gauge approximates to 2 mm2. I use 18 gauge or 22 gauge for the droppers. 1 mm2 or 0.75 mm2 would be the closest metric wire sizing.

What we should actually be interested in is the resistance of the wire and the associated voltage drop. This is the reason for a large diameter bus wire, and short and frequent droppers of a smaller diameter every 3 feet /1 m. Nickel silver brass alloy rail has significant resistance and voltage drops over long runs, one of the reasons for wiring droppers at regular intervals. Even a short or small layout will have small voltage drops that can impact running (DCC control still runs the motor with PWM DC current even although the track is half phase AC).

14 gauge/2mm2 wire is good for around 6 Amp for power transmission (long distance), 32 Amp for chassis wiring (short distance), over a distance of 0-50 feet it is usually good for 18 Amp (15 Amp over 15 m). For 18 gauge wire this drops to 19 Amp and 2.3 Amp respectively, over a distance of 0-50 feet it is good for 10 Amp (7 Amp over 15 m).

Look at the small diameter of the wires of ESU decoders (around 28 gauge) and the frog wires supplied with Peco switches (similar). What we wire a layout with is far beyond the requirements of the decoder or the motor. It is the requirement for minimizing the voltage drop that dictates the wiring size, along with the fact that a large layout may be running 4-5 locomotives at once (and require 10 gauge/6mm2 bus wiring). My small layouts run perfectly fine using an NCE system with a 2 Amp nominal output. Usually good for 2-3 modern locomotives or 1 old dinosaur.

Good practice to wire in a circuit breaker (or more for a larger layout with power sectors or blocks) in case of electrical shorts.

I know absolutely nothing about AC power or control of AC motors (domestic wiring excepted).

Nigel


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Hi Nigel,
Me I am re-motorising some older "dinosaur" kits or older DC locos from time to time or I am adding digital decoders to them.

For my bus wiring I use 2,5 sq mm under the modules or planks.

My DCC Unit has a 3 A nominal output to the layout. For my project it is enough.

The modules should be used to be joined together on meeting with other modellers.





                 

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