I imagine there are different styles of power routhing. All I have used are old style Shinohara/Walthers power routing turnouts with solid metal frogs.
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With these turnouts, the frog, points, closure rails, and all rails through the frog will have the same polatity, based on which stock rail the points are in contact with.
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The route the points are aligned with will have both positive and negative, so the locomotive will run. on the other route, both rails will either both be positive or both be negative, so the locomotive will not run.
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This does not work well with DCC because even tracks where a locomotive is stopped, it should still have power.
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The easiest way to make DCC work with power routing solid metal frogs was to gap both rails just beyond the frog and run jumper wires to keep all rails powered. Then, Walthers/Shinohara released the “DCC Friendly” turnouts which are not power routing.
Early turnouts that were scratch made were generally power routing because it was difficult to insulate the frog. Thus the current passed to the frog through whichever point rail was in contact with the stock rail.
Power had to be fed from the point end of the turnout because, yes, the two rails of the non-selected route were the same polarity, thus would cause a short. In any case where two power routing turnouts faced each other “frog-to-frog” you had to have an insulated gap somewhere between them.
Power routing turnout points are electrically common whereas all-live turnout points are insulated from each other.
The upper turnout is power routing (solid metal tie-bar) and below is an all-live (AKA DCC “Friendly”) insulated tie bar.
After plastic insulated frogs came along (Atlas Snap Switch) the All Live turnout was a popular choice because you could snap them into place and not be concerned with any special wiring “rules”.
Kevin’s picture says it all. The route not selected has both rails the same polarity, so nothing moves past the turnout.
The normal use of these feature depends on the other trackage.
On a main line, you would put a gap somewhere past the frog. And then feed that next section seperately. If the gap is far enough past the frog, this turns into collision protection. A train approaching from the frog end would hit the dead spot if the turnout is not aligned to that route…
A dead end siding needs no gap past the frog, when the trunout is aligned to the siding , it is powered, aligned to the main, the siding is dead.
Pretty simple actually.
All the turnouts on my first layout were TruScale all rail turnouts with these features - learned all this when I was 10…
I only dabble with the electronics aspect of the hobby, and Kevin’s picture depicts my understanding of the power routing turnout.
Power routing turnout’s, IMO, are primarily useful on DC layouts. An example that I understand is when two trains are approaching a passing siding from the opposite directions, one train can park on the siding when the power is routed to the siding. Then the turnouts are thrown back to the main line where the other train can pass and the parked train doesn’t move because the power is not routed to the siding. Then as the second train moves on (probably to another DC block), the turnouts are thrown back to the siding, which powers it, and the train moves on.
I’m sure there are other useful applications of such a turnout, but I tend to run one train on the layout so having every track powered doesn’t cause issues. Its something I’ve really never had to deal with.
Because I don’t use PECO turnouts, and don’t have any on hand to test, and don’t want to rely on old product info or memories from years ago, I have stayed out of the Richard/PECO/power routing conversation for the most part.
Not to mention that I don’t use DCC, despite my knowledge of how it works, I will leave that conversation to those who have the latest PECO track in hand.
Personally, I have never cared for their sprung throwbar or their electrical approaches.
But original old school DC power routing with turnouts made completely from rail work like Kevin’s diagr
Plenty of people have previously posted that they use old Shinohara turnouts with DCC. Back in the day I powered the frogs of those with Rix Rack switch machines and DC track power. The frog rails were connected with insulating rail joiners. The diverging route was powered by a separate toggle switch, not the position of the points.
I still have a handful of the Rix machines and a couple of the turnouts, though they were damaged in the salvage process. Maybe one of the turnouts is still usable. I never liked the snap ot the Rix.
I’m not meaning to be critical here, but I can sense some of Ed’s frustration with those who don’t have “old school” DC experiance.
I realize many of you just don’t care how we did it “back in the dark ages”, but Paul Mallery’s two books on wiring would be a good place for many to learn some valueable basics…
And I know many of you think I’m nuts with my DC and relays…but my trains can’t run red signals, I have ATC, and it was free…
The entire route power goes through the routing turnout as in my drawing below?
In the case of a Peco Insulfrog SL-8352 (my drawing above) the full route current would flow through the point rail connection to the stock rail? The SL-8352 (new out of the package) does not have the point contact that slides under the stock rail meaning that the connection of the point rail against the stock rail is passing the entire route current?
EDIT:
Just wanted to let everyone know I have 68 years old school HO DC knowledge. I just didn’t understand the reasoning for Power Routing or why the point rails needed to carry the full current.
That is the same thing. Almost. It’s always just the two center rails tha tmeet at the frog that switch polarity or get cut off, since the curved stock rail comign from the points is all one peice of rail, and the straight stock rail from the poitn side is one peice of rail. Those rails are always conencted to some feed somewhere.
The only difference in what happens to the two diverging rails past the frog depends on how the rest of the turnotu is constructed. If the two poitn rails are insualted form one another, as in the Insulfrog, and there are no internal jumpers between the stock r
I guess I have to admit I have used a form of “Power Routing”. Back when I first got into HO (1951) I hand laid all my track and built my turnouts from the antiquated steel (iron) rails so all of my frogs were soldered “Power Routing” but only for a couple of inches to the gap (didn’t have insolated joiners back then). I don’t remember even using joiners until the first brass flex track arrived on the scene around 1958 or so.
Generally, the all live turnout has an isolated frog, sometimes made of plastic so there is no reason to try to power it. Other all-live designs have a metal frog but is electrically isolated from the stock or closure rails so an additional method of bringing current to the frog is an option. Some modelers with long wheelbase locomotives or short frogs may never need to supply power to the frog.
Itherwise, the frog may be powered but the frog polarity has to change to match the polarity of the closure rail thus the use of auxiliary electrical devices (SPDT switch or "frog juicer) to change the frog polarity.
Randy is correct that some power routing turnouts do not have the point rails joined as my photo implies. The Shinohara brand does join the point rails electrically. Walthers also added confusion to the field by coining that “DCC Friendly” term to indicate an all-live turnout.
seems that “power routing” and “dcc friendly” share features.
i thought DCC friendly turnouts avoid the possibility of a short between the unused points rail and stock rail by an out of gage wheel.
A common approach is to isolate the points rails from the frog and power them from the adjacent stock rail. Powering the frog must use some other mechanism
unpowering the unused points rail is an alternate approach and it looks like the approach taken by Peco if the frog rails are not externally powered.
Not all manufacturers internally wire turnouts the same. There are no turnout wiring “police”.
In the old days, there were no totally isolated frogs. The all rail metal frog was electrically and mechanically part of the closure rails, the points and the frog rails past the frog.
And yes, the open point rail and the stock rail were opposite polarity.
Again see Kevin’s drawing, I don’t do computer drawings…
Then ATLAS (and others) made plastic frogs and jumped the wiring under the frog, keeping the two points/closure rails, and the frog rails past the frog, isolated from each other. There by eliminating power routing, and the need for gaps after the frog.
Then ATLAS (and others) totally isolated a metal frog, kept the jumpers, and created the option to power the unpowered metal frog.
Then others (like PECO) included jumpers, that can be removed to make the turnout behave in various different ways, and build both metal frog and plastic frog versions of same.
Think about it, draw a picture If you scratch built a single turnout completely from metal rail and installed it in a simple loop of track, and hooked up a simple DC power pack, as soon as you threw the switch to the diverging route you would have a short circuit.
You would be connecting the left rail to the right rail.
when i build turnouts, the point/closure rails and frog are electrically connected. I don’t connect the frog rails to the adjacent rails (gap). I rely on the point rail contact with the stock rail (not so reliable).
while not “DCC friendly”, i’d consider this power routing (as well as routing power to the frog) and works fine with DCC.
seems that a spur could be power routed by either NOT powering a rail or making both spur rails the same polarity (and voltage).
seems there are various ways these features (i.e. “power routing”, “DCC friendly”) can be implemented, so these terms are ambiguous.
