seems like a silly and simple question but i would rather ask it than screw something up. anyway why do frogs need power, from a dcc stand point? and i noticed the wiring diagram on the back of a atlas code 55 turnout seems like the frogs power can be reversed depending on the switch position why is this needed and how does it pertain to dcc. if you havent guessed im in the process of my track work using atlas 55 track, with a digitrax zephyr. also i would like to know of a reliable turnout motor thats compatable with the atlas turnouts and the digitrax system.
Good turnout wiring is the same, whether you use DC or DCC. Live frogs work the same in DC or DCC, too.
Live frogs:
The choice of live or dead frogs is yours with most Atlas Custom Line turnouts.
On DC layouts the turnout motors (switch machines) are usually powered independently from track power. In DCC, you can power a Tortoise-type motor and throw the turnout with the DCC system. Or you can keep it independent, just like DC. Independent operation of turnouts is my personal preference. With independent operation, any turnout motor can be used, including Atlas switch machines and various manual throws. With independent operation, you can still throw your turnout even if the layout has a short circuit which has caused the DCC system to shut down.
If you use twin coil switch machines (like Atlas), I strongly recommend you use a Capacitive Discharge (CD) Unit in conjunction with your switch machine power. Your switch machines and their controls will thank you. And you can use a smaller power supply for switch machine power.
my thoughts, your choices
Fred W
''If you use twin coil switch machines (like Atlas), I strongly recommend you use a Capacitive Discharge (CD) Unit in conjunction with your switch machine power. ''
What type of cd are you referring to. is it something digitrax offers? im still pretty green when it comes to dcc wiring.
A Capacitive Discharge Unit is not a DCC-peculiar piece of gear. A CD unit stores up a healthy charge in a capacitor(s). When the control switch is pressed to throw the turnout, the capacitor delivers a "jolt" of electrical energy to the switch machine, which quickly tapers off to almost nothing. The capacitor takes a second or so to recharge. Twin coil machines need a burst of energy to throw the turnout and then the power should be shut off. If power is not shut off within a second or two, the twin coil switch machine overheats, and in the case of Atlas melts the plastic case, causing the machine to lock up. A CD unit automatically shuts the current off after a brief burst.
The CD unit has nothing to do whether you use DCC or DC to run your trains; it is a better power supply for throwing twin coil switch machines.
Commercial CD units are made by Circuitron (there are others), or you can easily build one yourself. See http://home.cogeco.ca/~rpaisley4/CDPSU.html for circuits and other help.
However if you plan to control the turnouts via DCC, some of the DCC stationary decoders designed for twin-coil motors liek the Atlas already have a CD power supply built in. You generally can NOT use a standalone CD power supply to operate switch motors via a DCC stationary decoder. Control via buttons: use a CD supply, best investment you'll make. DCC operation: use one of the decoders that has the CD supply built in, and if it offers an option to hook up an external power source, use the specified one. That way it won't draw from track power every time you throw a switch.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
rrinker However if you plan to control the turnouts via DCC, some of the DCC stationary decoders designed for twin-coil motors liek the Atlas already have a CD power supply built in. You generally can NOT use a standalone CD power supply to operate switch motors via a DCC stationary decoder. Control via buttons: use a CD supply, best investment you'll make. DCC operation: use one of the decoders that has the CD supply built in, and if it offers an option to hook up an external power source, use the specified one. That way it won't draw from track power every time you throw a switch. --Randy
Randy
Thanks for the additional info. I was not aware of the features of some DCC stationary decoder/turnout controls. Learned something myself.
If you're placing your turnouts where they're hard to reach, or plan to operate them remotely, I highly recommend Tortoise slow motion switch machines by Circuitron. They're a little pricey, but they are bulletproof, and provide extra terminals for routing the power to the frog. If you can reach them, and don't mind throwing a switch here and there (all the best brakemen do it!) the I recommend the micro slide switches I illustrated in your other thread.
Lee
Route of the Alpha Jets www.wmrywesternlines.net
Raised on the Erie Lackawanna Mainline- Supt. of the Black River Transfer & Terminal R.R.
The O.P. is working in N scale, and the biggest reason for powering the frog is to prevent unseemly stalls with small engines at slow speeds.
Capt. GrimekWith power routed (live UNinsulated frogs) turn outs you can shut down the power on a yard track by throwing the turnout switch. This will keep sound locos unpowered and quiet and better for their DCC powered motors. What I'm trying to find out is whether or not there are other uses for power routed turn outs? I'm having a hard time decided whether to include them in places other than the yards and if so, why It's an advantage. Thoughts? Thanks.
The advantage of power routing was to reduce the number of block toggles in DC block wiring. Letting the turnout control the power to a spur saved a toggle switch that would otherwise be needed to turn the spur off or select which throttle powered the spur.
The assumption in power routing is that throwing the turnout against the spur will always happen when you want to shut the power off to the spur. And that you will never want power to the spur when the turnout is thrown against it. The reasons for throwing a turnout may not always be the same as for turning power on/off on a spur, but with power routing you are locked into both happening at the same time.
The second assumption is certainly not always true with DCC. There are times when you may want to access the locomotive that is on the spur, even though the turnout is thrown against it. You may want to turn idle sound or lights on or off. You may want to add the locomotive to a consist. You may want to alter some CVs. None of this is possible with power routing and the turnout thrown against the locomotive. IMHO, it is far better to install the toggle switch than to use power routing with DCC. This is theoretical for me since I don't have DCC yet, but I would think it would be better to mute the sound with the throttle than to use power routing to kill power to the decoder.
RE Power routing turnouts:
Adding to Fred's comments: Power routing turnouts that rely on power contact between the points and the stock rail or on plates underneath the rails, can become unreliable over time. I know several modelers who have very large layouts that spend a fair amount of time cleaning the contact points on these switches to keep the power flowing. These switches generally work great when you first install them but begin to have problems down the road after the effects of ballasting, painting, dirt and wear begin to work on them. I prefer to hard wire the points/closure rail and use a powered frog for super reliable electrical contact.
With DCC, I would recommend powering both sides of the turnout (with correct gapping) and having the whole set-up live. If you want to control power to the section of track, gap and use a kill switch at the panel. I have found with a large layout using DCC, that there are times that I want to park trains and kill power to the sound decoders. Keeps the racket down and the decoders are not sitting there fired up while not in use. This also cuts down on the exposure of the decoder in a parked train to surges that happen during shorts on other parts of the layout. It can also be a protection against inadvertently assigning a throttle to the wrong loco and driving it off the siding etc.(don't ask). I have plans to go back and add some more blocks/kill switches to the layout for this purpose.
My two cents,
Guy
see stuff at: the Willoughby Line Site
im a little confused when it comes to turnout powering with the correct polarity and properly gapping a turnout. can someone explain this to me with a little more detail im using digitrax dcc and i would like my frogs to have the right power due to some of the smaller locos that i run. im using atlas 55 track and i noticed the diagram on the back of a turnout package on powering the frogs with the atlas snap switch and to me it seems like it would work for dcc however im still pretty green when it comes to dcc turnout wiring and control. any help is appreciated. thanks
mmr
If you're controllign your switch motors with the pushbutton controllers and not using DCC to throw them, the diagram on the package using the Snap Relay is exactly how you will wire it. If you look at how the turnout works, you can see how the frog needs to be wired. Notice tha tthe two moving rails will touch one or the other straight rails at the entrance of the turnout. Whichever rail is being touched is the one that needs to connect to the frog. It's pretty obvious when you look at the switch and follow along which path the train will take.
yeah you are right, however i am going to be controlling the turnout through dcc, a digitrax ds64 is being used as my stationary decoder and it does allready have a cd unit buit in so it should be abel to provide enough power with out damaging the turnout switch. so im assuming that the turnout will have to be wired differently than the diagram however to me it seems as though it would still work because the ds64 is just sending power to the switch and the snap switch is doing the work through its contacts ( reversing polarity back and fourth to the frog). dont mistake me i could be dead wrong just trying to learn. any thoughts? thanks
There's no difference wiring the contacts for frog power. It doesn't matter what source of power makes the switch motor and snap relay move, the contacts on the snap relay are independent of the input - they are just like a toggle switch.
I have a DCC powered N-scale layout with Peco turnouts and Tortoise switch machines. Use insulted frogs !! N or HO DCC layouts --- powdered or eletrified frogs must be insultaed beyond the frog - and you need to be careful how to hook up power to the turnout. Also, you need to 'power route' the frog ... provide a way to change the electrical polarity to the frog when you throw the switch from normal to diverging (I use the auxillary contacts on the Tortoise machines). If you use insulated frog type turnouts, you do NOT have to do this - much simpler ! Almost all N-scale locos now, and I assume HO locos have multi-axle or multi-truck electrical pickups so the very short insulated area of an insulated frog is no longer a problem. HO or N -- for DCC - go with insulated frog -- trust me -- is much more user friendly ! Good luck !
fwrightCapt. GrimekWith power routed (live UNinsulated frogs) turn outs you can shut down the power on a yard track by throwing the turnout switch. This will keep sound locos unpowered and quiet and better for their DCC powered motors. What I'm trying to find out is whether or not there are other uses for power routed turn outs? I'm having a hard time decided whether to include them in places other than the yards and if so, why It's an advantage. Thoughts? Thanks. The advantage of power routing was to reduce the number of block toggles in DC block wiring. Letting the turnout control the power to a spur saved a toggle switch that would otherwise be needed to turn the spur off or select which throttle powered the spur. The assumption in power routing is that throwing the turnout against the spur will always happen when you want to shut the power off to the spur. And that you will never want power to the spur when the turnout is thrown against it. The reasons for throwing a turnout may not always be the same as for turning power on/off on a spur, but with power routing you are locked into both happening at the same time.
If you have a double ended yard, power routing switches will give you shorts when one end of a track is thrown for the track and the other end isn't. Worse, if the switches are thrown in the right pattern, power will feed down one track, through the switch at the other end, and back into the next track, causing an engine parked there to suddenly spring to life and run (or even worse, shove a long train) through a switch that's against it (obviously, this can only happen in DC, not DCC, unless the engine parked there is still assigned to a throttle that's running a train somewhere else on the layout).
David S