Actually, my 3' wire was more to do with amperage. Too low amps won't run an engine. It's the garden hose story. If you could hook a garden hose to a fire hydrant, the water coming out at other end would fly like 50 yards. That's what amperage is, to me. I know the throttle or power pack creates the amps not the wire. It was a lame way of saying thinner wire will handle it if not too thin, and so, 18, 22, 24 gauges are too thick to work with (soldering/bending/toggle posts). And I think if it IS 3' thick copper it acts like a capacitor, no ? There's room to store electrons until they accumulate enough to cover the surface of the conductor, then flow with low amps at other end, No ?
No. Wires do not behave like capacitors, regardless of gauge. The OP needs to concern themselves with two things, the ease of manipulating smaller gauge wire (higher number) and distance of run which to overcome resistance requires larger gauge wire (lower number). Not taking resistance into consideration can lead to hot wires which in worse case scenario will lead to melted insulation and or fire. There are charts online that outline minimum to ideal gauge for given run in both stranded and solid wire at both a given voltage or given amperage, and though related are not the same thing. Running large gauge bus wire and short feeders to the track is the best option to overcome both limitations inherent in wires and insure strong electrical connection and signal in the case of DCC.
Your understanding of electricity is seriously flawed. If we could create your hypothetical wiring scheme with gargantuan copper "bus wires," it would look something like this: Except for the fact that each gargantuan "bus wire" would weigh approximately 300,000 pounds, the arrangement above would work splendidly! As Chris said above, a wire is not a capacitor and does not "store" electrons and "accumulate" them in the manner you seem to believe. - Jeff
I just thought of this as I'm out in the garage working on my Jeep... Were you somehow equating how a modern vehicle 12v system is chassis ground to how copper wire works? In that instance I can kinda see the relationship. Electrons do flow freely through the steel body but in over such a large surface area that you don't get jolted by touching it as if you were to hold the battery cables by stripped ends. However copper is not steel and in neither case is energy stored, only capacitors and batteries can store electricity in its active form. Anyway, I think we're getting off topic and have addressed the OP's question and can drop this.
This is also incorrect. You don't get shocked touching the steel body of the car because you are only touching ground and not touching the positive to complete the circuit - it's like a bird sitting on a power wire.
You can touch battery positive and the body at the same time, granted the body is painted but still conducts electricity. Except in the rain. Don't mess with car batteries in the rain. Darnit, we're sidetracked again!
The plumbing comparison has always fallen short when trying to explain electricity. Increasing the diameter of wire does not reduce the pressure (voltage). Increasing wire diameter increases the volume (current) of electrons the wire can carry. Voltage (pressure) remains the same. This is not the same as fluid going through a pipe. Martin Myers
Actually I was just trying to steer the PO away from either too thin wire ( heating /melting Pos. ) and too fat wire ( not user-friendly in the hobby) . Thanks for corrections. But, I do have a electricity question: Isn't it that if you are wearing rubber boots you CAN touch say, the 600v 3rd rail because you are not making a circuit, the boots being insulators ? Don't you get zapped when you DO complete the circuit, now in your bare feet ? Finally, I will explain this next question after replies and explain why so : Does leather, particularly shoe sole leather conduct electricity ?
If my memory of organic chem class serves... Rubber is an excellent insulator compared to leather. Remember, leather has to retain moisture or it disintegrates because it is an organic fabric made of lipids and proteins. Rubber has to retain some moisture or it dry rots, but not nearly as much as leather, and the chemical structure of how the h2o is retained between the two is very different.
The lack of understanding the relationship of wire size for DCC never ceases to amaze me. Still clinging to the rules of DC or 60HZ via the American Wire Tables is like trying to run a semi tractor trailer rig using gasoline. DCC has so much high frequency content that it is absurd to think DC rules and practice would work well. Solve the combination of the carrier frequency, the pulse repetition frequency and the the actual internal pulse frequency and so on. Then you will see what is really happening. This means solving the Convolution integration of all the different waveforms etc. If you need a real reference see: Digital Communications by John G. Proakis ISBN 0-7-07-050927-1 Digital Filters by R.W. Hamming ISBN 0-13-212506-4 Fields and Waves in Communication Electronics by Simon Ramo, John R. Whinnery, Theodore Van Duzer ISBN 0-471-70720-1 A compounded Digital signal has nothing in common with DC or with 60Hz sine waves. Inferring that they are comparable and compatible is still like using gas in a semi. Oh, and an even bigger part of the truth is the quality of the copper not the size.
Sorry, Mark I've read this thread through twice and missed it. What was the questions? Does a hose hooked to the layout help the trains run better? Only if it is hooked up to plumbing suitable to serve water spouts and the locomotives are live steamers. Sorry, I couldn't resist. By the way, I thread in and solder solid wire, 18 gauge, to the backside of DPDT's or whatever switch is required... all day long. Now 14 gauge wire... no, not at all. I won't even try that. That's like a colonoscopy for an elephant. Oop's there I go making none related comparisons. Some where is a DPDT, DCC, Cab A and Cab B 20 and 18 gauge wire discussion, I submitted here on TB. Here we go the revised version on BRick.com. http://www.barstowrick.com/category/wiring/ I talk about things and how it works for me. However, I will defer to David for the technical explanation.
I have a question about power supplies for Digitrax. I hope it is OK to ask it here. Digtrax say that " Accepts either 50/60 Hz AC or DC input from power supply (sold separately). Recommended power supply: Digitrax PS514 or equivalent. Maximum input 22 volts AC or 28 volts DC Minimum input 12 volts AC or 12 volts DC" With that info, I can find a power supply for a laptop computer that falls in the range stated a lot cheaper than any thing else. Would it be OK to use this type of power supply? Specs: 18.5 volts DC 6.5 amps 120 watts Overload protected
Our group has been using this the following on with 5 and 8 amp boosters from Digitrax; http://www.powerwerx.com/power-supp...esktop-switching-power-supply-powerpoles.html or http://www.powerwerx.com/power-supplies/variable-digital-meters-30-amp-desktop-power-supply.html I am considering this because of the price, http://www.radioshack.com/radioshack-13-8vdc-15a-power-supply/2200508.html All have cooling fans and are over kill. Any thoughts?
This one looks promising too, http://www.ebay.com/itm/271244336192?_trksid=p2060778.m1438.l2649&ssPageName=STRK:MEBIDX:IT
wouldnt do eighter one of those,,,,,you will be a crispy critter. 600v DC or AC would require more protection to work on or to conatct. Tony's trains.com has a 5 amp regulated power suppy for around $34 dollars, and they work very well. Just a wall wart that has two wires that go to your command center. To use a computer power suppy will cause a melt down of the supply because its not made for the current demand. As far a circuit protection thats what the command station does or curcuit protectors on the load side of the command station. And Im not sure why you would need SPDT switches on the power.....thats why DCC is so nice, you dont have you use them, you run the trains not the track. Jim
Purple1.......I wouldn't use a computer charger for your digitrax command station because it doesnt have the amperage capacity for your use. Im sure they are about an amp or less, and it will not have the ability to run anything. Not even sure it could power up a BDL168 or SE8c. Jim
