I just checked Paul Mallery's Electrical Handbook for Model Railroads vol 2. He says DC is recommended for twin coil machines for control performance and protection. A capacitor discharge device is a very good idea for twin coil machines. Using DC power allows diode matrixes to be used for controlling multipe machine on a route with one set of pushbuttons
Ron High
A good source of wire for engines and cars are telephone set cords the type that go from the baseboard or wall jackto the set. You want D8W cords with the wire visible in the modular plug it will show blue,orange,black,red,green,yellow,brown,slate.The wire is small (28 guage?)stranded very flexible copper. They come in lengths starting at 7 feet. they are commonlycovered with ivory or silver or gray soft plastic .They were used in AT&T Lucent and Avaya telephone systems and maybe others. There are many anywhere these telephone systems were used .You can find them new online ,do a search for D8W cord.
a retired telephone man
markie97 A lot of good info here. Can anyone comment on activating a twin coil machine with DC vs AC voltage? I beleive one will create less arcing vs the other but I cannot remeber which.
A lot of good info here. Can anyone comment on activating a twin coil machine with DC vs AC voltage? I beleive one will create less arcing vs the other but I cannot remeber which.
I don't use twin coils, but I'd guess AC gives less arcing, because electricity is flowing both ways across any contact surface. Then again, that's if AC is OK to use with them.
Mike Lehman
Urbana, IL
cacoleThere's a possibility that a wal-wart can overheat or short out and catch fire if it's left plugged in all the time...
True, so I have the wallwarts I use for my power supplies on one of the two main power circuits, which are shut down when the layout is not in use.
We use a computer power supply for lights, switch motors, and signals on our large HO scale club layout. Two power bus lines were ran from it around the layout, one for 12 VDC and one for 5 VDC. It is turned on and off with the main power switch that controls the layout's DCC system, so everything is turned off when no one is at the clubhouse.
There's a possibility that a wal-wart can overheat or short out and catch fire if it's left plugged in all the time, so they can be a fire hazard, especially the really cheap, low-power ones that come with cell phone chargers and the like. You're also wasting electricity with a wall-wart plugged in continuously and not actually in use.
Thank you
Guy,
No problem, it sounds like you had some issues and solved them.
I'm all Tortoise when it comes to switch machines, with a few manual throws. I suspect, like the critter they're named after, they'll run on just about anything they get fed -- except AC
I think I have about a half-dozen circuits, although I've never sat down to count them. I'l confess to some laxity about things like power supplies and documentation. Been lucky enough to never have a power supply fail -- so far. There are a few places where there is some overlap between power supplies, but in most places on the layout they group together pretty naturally so relatively easy to troubleshoot.
see stuff at: the Willoughby Line Site
mlehmanBTW, while off-topic to this particular inquiry, it's still the Electronics and DCC forum, so while you're in the thrift store, check to see if they have mice -- the computer kind. Buy them for the "tails" -- working or not, doesn't matter -- because the wire in mouse cords is IDEAL in most cases to use for decoders and other wiring inside locos and cars. It's almost always cheaper to buy it this way than in the custom packs that model RR suppliers sell. In any case, we never throw a corded mouse away around here until it's no longer corded.
Sources of wire are hardly off topic! LION (as network administrator) has dead mice by the hundreds : All have had their tails clipped. Him uses the tails to connect signals on the layout.
Another excelent source of fine wire is the old parallel port printer cables. The old ones have 25 conductors, the newer ones have 25 pair of conductors. And now that computers no longer come with parallel ports, all they are good for is the layout.
Cat 5 wire is a good source of hookup wire. I priced out 22 ga wire and the best deal is to buy new Cat 5 cable and strip out the conductors. Or use them whole if you need four pair together for something. Do not hesitate to buy a 1000' box of the stuff if your layout is cable intensive. LION recently bought 100' of 25 pair Cat 3 cables for some of his long cable runs.
USB cables are a good source of wire, but I am not releasing those to the train room.
ROAR
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
MisterBeasleyNOTE TO ALL USERS OF SMALL POWER SUPPLIES: Most of these do not have circuit breakers. Instead, they have internal fuses to guard against fire danger from overloading and make them UL compliant. These fuses are not replaceable. Once they're gone, you've got a paperweight with a wire on it. So, get a fuse holder and a fuse, preferably one rated about 20% less than the supply.
Good Plan. Old soldering irons of LION were power neutral and I could solder on live circuits.
New solder station of LION has grounded iron tip. It shorts out any live circuit that I work on. Fortunately the 16v wall ward used for my signal system does have a automatic reset protection: unplug it, and plug it in again. All fixed. But I try to remember ot power down the layout before I solder to the circuits now.
riogrande5761So where do you get these walwarts you speak of? Like I know we often accumulate them from lost electronic devices but they have all manner of voltages etc.
Jim,
Yes, some of mine are just surplus wallwarts from defunct electronic gear. Anything DC from about 7.5 volts to 12 volts will work. I just cut the stock plug off, leaving a foot or two of the wire, then simply wire that into the Tortoise supply circuit.
How many Tortoises will they serve? Depends on the millamp output. I forget what the Tortoise drawd when stalled, but you simply divide the wallwart's millamp output by that to tell you about how many it will power. I have about two dozen on each of mine with supplies ranging from a half amp to around a full amp.
AC won't work. I think that down to 6 volts does work, but movement is slower when thrown, not necessarily a bad thing.
If no surplus ones around -- remember to try Goodwill or other thrift shops for a bargain -- then Radio Shack has them in whatever you'd like to try.
BTW, while off-topic to this particular inquiry, it's still the Electronics and DCC forum, so while you're in the thrift store, check to see if they have mice -- the computer kind. Buy them for the "tails" -- working or not, doesn't matter -- because the wire in mouse cords is IDEAL in most cases to use for decoders and other wiring inside locos and cars. It's almost always cheaper to buy it this way than in the custom packs that model RR suppliers sell. In any case, we never throw a corded mouse away around here until it's no longer corded.
I save wall warts when we throw away some outdated computer gizmo, cell phone or other electronic doo-dad. You might find a computer show near you, which would probably have some vendor with a bunch of used ones for a dollar or two. When I put one on my layout, I like to write its specs on a small piece of white paper and then attach it to the wall wart with Scotch tape, so I can read it easily.
I went to All Electronics online for larger supplies to use with structure lights and street lamps. I ran them with wall warts for a while, but after a while those 30 millamp bulbs add up, and I was beyond the capacity of those little power supplies.
NOTE TO ALL USERS OF SMALL POWER SUPPLIES: Most of these do not have circuit breakers. Instead, they have internal fuses to guard against fire danger from overloading and make them UL compliant. These fuses are not replaceable. Once they're gone, you've got a paperweight with a wire on it. So, get a fuse holder and a fuse, preferably one rated about 20% less than the supply.
It takes an iron man to play with a toy iron horse.
So where do you get these walwarts you speak of? Like I know we often accumulate them from lost electronic devices but they have all manner of voltages etc.
As for Cap Discharge Units, I would guess there are a variety of them out there; anyone care to offer a quick survey of what is available and what would be an economical option?
Rio Grande. The Action Road - Focus 1977-1983
trainnut1250From someone who has 70+ stall motors installed: Use a regulated power supply for the stall motors. This rules out most wall warts. The voltage in an unregulated power supply will drop as the amperage load increases - In a 12 volt supply they typically run 14 volts and then drop down to 12 volts as you add load to them Most stall motors require a resistor to drop voltage. As you add motors to the circuit, the voltage will drop.
I'm not sure about the need for a regulated supply with stall motors. The Tortoise doesn't need an external resistor, at least none of mine have it. All are powered from wallwarts.
You'll know when you have too many on the power supply, in case you don't keep track. I don't. I just wait until I add another Tortoise and throwing the switch on it doesn't work, even though wired properly. Then I add another wallwart circuit.
True, the wallwarts tend to put out too much current if lightly loaded. I usually deal with that by taking part of the load off the overloaded wall wart and starting the new power circuit with multiple machines on it. That helps pull down the voltage to a reasonable level. Another ootion is to use a 9 volt wallwart, as you don't need 12 volts to throw the Tortoise.
wp8thsub I use an old Bachmann power pack (one of the metal jobs from the '70s) to power all my switch machines that aren't run with accessory decoders. I have them connected to the variable DC output, and adjusted it until they all threw properly. My machines are Switchmasters, but I'm sure you could run solenoid type machines too.
I use an old Bachmann power pack (one of the metal jobs from the '70s) to power all my switch machines that aren't run with accessory decoders. I have them connected to the variable DC output, and adjusted it until they all threw properly. My machines are Switchmasters, but I'm sure you could run solenoid type machines too.
Thats basically my plan. I picked up a little metal power pack for next to nothing a train show with thoughts of using the variable DC output for the Switchmaster machines I have and the AC outlet to the solinoid machines. It was literally a 2 or 3 dollars for the power pack so I theorized it could work for this purpose! I go cheap where I can with a daughter in college!
Rob Spangler
LION has 2 5W 12v Transformers with rectifiers as per my diagram below.
You can do the same thing with two 12v dc wall warts. Cut the output plugs off of them and wire them per my diagram.
You will have a GROUND; +12vdc; and -12vdc. With this you naturally have a GROUND bus running around you layout. Do GROUND it to the building ground to avoid stray voltage on this wire, which will drive you crazy.
The rest of your circuits look something like this. The Advantage that the LION likes is that a single wire between the control panel and the turnout saves money on cables, and wires are VERY EXPENSIVE.
riogrande5761 The walward sounds like a great idea for the stall switch machines. I picked up an inexpensive train set styles power pack at a train show in very good condition with plans to use it for accessories and/or switch machines. I have a Digitrax radio Chief for train control. Also a Star Tech Hogger walk around DC throttle which could be used also for auxilary power.
The walward sounds like a great idea for the stall switch machines. I picked up an inexpensive train set styles power pack at a train show in very good condition with plans to use it for accessories and/or switch machines. I have a Digitrax radio Chief for train control. Also a Star Tech Hogger walk around DC throttle which could be used also for auxilary power.
From someone who has 70+ stall motors installed: Use a regulated power supply for the stall motors. This rules out most wall warts. The voltage in an unregulated power supply will drop as the amperage load increases - In a 12 volt supply they typically run 14 volts and then drop down to 12 volts as you add load to them
Most stall motors require a resistor to drop voltage. As you add motors to the circuit, the voltage will drop. As it does, the motors set first at the higher voltage (bigger resistors) will begin to stick. If you are running only a few motors this might not be an issue. On a large layout it can be a headache. Just something to be aware of...
Guy
I use my old train power pack's AC output to drive the CDU for my twin-coil turnouts, and the DC output to drive my turntable. Those are the only things driven by the power pack.
I, too, have a wall-wart for my Tortoises. It'a a 9-volt supply from some forgotten gadget.
An old power pack will work - However, I would not purchase one new or even a used one off of eBay. They may be fine for thowing a single switch machine. If you do use an old power pack, I would suggest get a C/D unit - less chance of fried switch macines.
Stall motor units usually require something like 12VDC - I have an old 'wall wart' form 'something' and it provides enough power for something like 55 Tortoise machines at ful stall.
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
Can an inexpensive train controller/power pack be used to power switch machines? Such as Atlas, Peco?
What about a couple of stall type Switchmaster switch machines?