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Track and Turnouts, regardless of make, don't care whether
you use DCC or DC. If a turnout works on a DC layout it'll
work just as well with DCC. The DCC system and the loco
decoders are your concern, nothing else matters to run
a DCC layout. Both DC and DCC require a smooth even
electrical conductivity. That means, you must keep your
track and the power pickup wheels of your locos clean.

Don
 

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Discussion Starter #3
Track and Turnouts, regardless of make, don't care whether
you use DCC or DC. If a turnout works on a DC layout it'll
work just as well with DCC. The DCC system and the loco
decoders are your concern, nothing else matters to run
a DCC layout. Both DC and DCC require a smooth even
electrical conductivity. That means, you must keep your
track and the power pickup wheels of your locos clean.

Don
ok, thank you. I just finished reading articles about electro frog and insul frogs and modifying turnouts and it sure seemed like there was a difference in turnouts. But maybe that is old news. So you are saying no difference at all we can buy any turnouts and be good to go with DCC, that is happy news, thank you.
 

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Spacecomp

A word of clarity might be in order.

You have read about ELECTROFROG and INSULFROG turnouts.

ELECTROFROG turnouts have a powered METAL frog. It is used
by layouts with some very small locos or locos that lack all wheel
power pickup. Most modern locos do not require them. The phase
(polarity) of the frog changes with the points. Thus, you must
place INSULATED joiners in both of the Frog rails to avoid
short circuits. Some makers use the term 'DCC compatible'
when describing these. It is pure nonsensical hype.

INSULFROG turnouts have a plastic frog. They are the most
commonly used type of turnout. They do not require insulated
joiners. But most are 'power routing'. That means when the
points are set to straight the power to the divert rails are cut.
Some use this feature on spurs used to 'store' unused locos.
Others, however, want 'always on' power so they add track drops
to the DCC bus for both frog rails.

The general recommendation for most layouts is to use
INSULFROG type of turnouts.


Don
 

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ok, thank you. I just finished reading articles about electro frog and insul frogs and modifying turnouts and it sure seemed like there was a difference in turnouts. But maybe that is old news. So you are saying no difference at all we can buy any turnouts and be good to go with DCC, that is happy news, thank you.
spacomp;

This may be some not so happy news. You were right the first time. There are physical/electrical differences in turnouts.

On your question about Kato Turnouts:
I don't use Kato Unitrack, or Kato turnouts, so I don't know for certain if they are OK with DCC or not. I did a little checking online. From what I can see in the rather small photos, The Kato turnouts have metal frogs which appear to be electrically, and physically, connected to both of the point rails. It does not look like there are insulated gaps around the frog. This is common practice in "power routing" turnouts. That type of turnout typically has opposite electrical polarities between each point rail, and its neighboring stock rail. If those guesses on my part are true, then the "DCC compatible/friendly" configuration would not be built into a Kato turnout, and would be difficult to add. That doesn't mean you couldn't use Kato turnouts with DCC. It may mean occasional short circuits between the point and stock rails though.

As for Peco turnouts, Peco's new Unifrog turnouts have the DCC friendly option built in. They come wired as Insulfrogs, but have a composite frog (part metal, part plastic) that is isolated, The Electrofrogs would need the modification you saw in the video, the Insulfrogs probably won't need modification.

Though I like, and respect, DonR, and we agree on many things, he and I are somewhat on opposite sides of this particular issue. It's not quite as simple as Don says. He's correct that any turnout can work with either DC or DCC, but more accurately, any turnout may be modified to work with DCC. They all work with DC without modification, and just to complicate matters, all can be used with DCC, but you may have some intermittent short circuits unless the turnouts are modified, depending on which turnout! (Now ain't that just clear as mud!)
It's a complex issue, and often the opinions are stated in an overly simple manner, like "Any turnout will work with DC or DCC.

The articles you read probably dealt with modifying the Peco Electrofrogs, to something called the DCC compatible/friendly configuration. (I don't think an Insulfrog would need any modification, maybe jumpers from the point to stock rail?)
Now right from the get go, there has been lots of conflicting, and sometimes inaccurate, information put out in commercial advertising, and in opinions expressed here, and on other forums about this subject.
Most of the conflict is a matter of degree, and how opinions are presented, rather than some hard and fast, drastic difference of fact between the two schools of thought.

So what is the real difference between a "DCC friendly" turnout, and any other turnout?
The DCC friendly turnout typically has an "isolated" metal frog. This means the frog is electrically insulated from all the other rails on the turnout. The other feature of the DCC friendly configuration is that the two moving point rails, are electrically insulated from one another, and each of the point rails is electrically jumpered to the non-moving stock rail next to it. I build my own turnouts this way. Isolated metal frog, point rails insulated from each other, and each individual point rail jumpered to its neighboring stock rail.

All of these specifications relate to a possible short circuit. Many turnouts have their point rails and the stock rails right next to them of opposite electrical polarities. A metal wheel might short the point rail to the stock rail, briefly.
If that happens on a traditional DC controlled layout, the operator might not even notice, because the slow-acting circuit breaker in a DC power pack, wouldn't have time enough to react to that brief a short circuit.

On a DCC layout though, things are different.
In order to protect themselves from damage, DCC controllers have very fast-acting circuit breakers. The same brief short circuit that didn't bother the DC power pack can shut down the DCC controller.
This is the idea behind the DCC friendly configuration, and thus "DCC friendly/compatible" turnout advertising.
If that same wheel, shorted the same rails, on a DCC friendly turnout, nothing would happen. The train would simply pass smoothly through the turnout, because the point and stock rails are the same electrical polarity, hence this short circuit is impossible.

The metal frog can either be powered or not, your choice. As Don pointed out, in his second response, powering a metal frog helps locomotives with few power pickups get across the frog and on through the turnout smoothly. Electrically the frog acts like any other piece of rail, and feeds power up to the locomotive.
Locomotives with all-wheel pickup can pass smoothly through a turnout with a "dead frog" that is either a metal frog not connected to any power, or a plastic frog, like the Peco "Insulfrog" turnouts, and Atlas "Snap Switch" turnouts have.
Speaking of Atlas Snap Switch turnout, I've recently been upgrading some for my grandson's layout. I notice that they "accidentally" have some of the DCC friendly features built in. (The Atlas and Peco designs predate the widespread use of DCC) The two point rails are insulated from one another, and the adjacent point, and stock, rails are jumpered to each other. All that's missing is the metal frog, and that's optional anyway. All these same things are true of a Peco Insulfrog too. So, in a way, they are "DCC friendly" turnouts too, right out of the box.

Traction Fan 🙂
 

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Discussion Starter #7
thanks. Boy, this is one answer I am going to have to read through a couple of times :)

I think I understand though.
 

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thanks. Boy, this is one answer I am going to have to read through a couple of times :)

I think I understand though.
spacomp;

Yes, it can be confusing all right. There are really some simple choices though.

1) You can do as Don suggested, and just use any turnout you want, without any electrical modification. If all the wheels on your railroad are in gauge, and whatever brand turnout you choose has flangeways that meet the NMRA gauge specs. Then you probably won't see the short circuit very often.
The catch here, (and the reason those videos, and I, recommend making electrical modifications) is this unfortunate fact. With the exception of Micro Engineering turnouts, every commercial turnout I've ever used * has flangeways that are too wide to meet the gauge's specs. Fortunately this is quite easy to fix, (in fact it's one of the upgrades I'm doing on my grandson's Atlas snap switch turnouts now.) The file below, "Improving Atlas turnouts" explains, starting on page eight, how this can be checked with an NMRA gauge and fixed with styrene shims glued into the flangeways. The main point of adding these shims is to prevent derailments, but a side benefit is that the properly gauged wheels and flangeways tend to keep those metal wheels from getting into a position where they could short the point and stock rails.

[ * I don't know whether the Kato turnouts you asked about Have flangeways that are too wide, or not, because I don't use Kato turnouts. ]

2) Since you may be modifying turnouts mechanically (by adding those shims) why not make the electrical modifications at the same time? None of the modifications, either mechanical, or electrical, is difficult at all.

3) You could choose to use turnouts that come DCC friendly/compatible right out of the box. Micro Engineering turnouts have the full DCC friendly configuration factory installed. They also don't have too wide flangeways. In fact, their flangeways are a tiny bit too narrow. A single pass with a Dremel tool, or some light filing will widen them to meet specs.
As mentioned, Peco Unifrog turnouts are also simple to wire as DCC friendly. In fact the only "wiring" involved is to connect the frog feeder wire that comes already on the turnout, to a "frog juicer" commercial circuit board.
Atlas code 55 N-scale turnouts also come with the DCC friendly configuration. There are probably others as well. These are just the ones I have used.

Sorry if I've given you a headache! 😕

Traction Fan 🙂
 

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Man, this all seems quite complicated! I just switched from DC to DCC and have had no trouble with the Kato turnouts. They have a metal frog and are power routing, but the polarity of the frog is determined by the stuff inside the turnout housing, not the contact by the point rail to the stock rail like in Peco Electro Frog.
 

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Man, this all seems quite complicated! I just switched from DC to DCC and have had no trouble with the Kato turnouts. They have a metal frog and are power routing, but the polarity of the frog is determined by the stuff inside the turnout housing, not the contact by the point rail to the stock rail like in Peco Electro Frog.
dd1228;

Thank you for the information. As I mentioned, I don't use Kato turnouts, so what little I know about them is gathered online, usually in small bits and pieces. Have you verified the polarity change in the frog with a meter?
I suspect you have just filled in one of the blanks in my limited information about Kato turnouts. In an online repair video, I got to see the inside of a Kato turnout. It had a set of electrical contacts that operated when the points were thrown. I was not sure whether they were used for frog polarity, or for some other purpose, like signals or control panel indicator lights. From what you say, they are most likely used to change the polarity of both the frog and the points attached to it. This would be a different way of making a turnout "DCC compatible" since the point rail and stock rail would be the same polarity. I'd appreciate it if you, or another Kato turnout user, would test this theory with a meter, and let me know the results.

Thanks;

Traction Fan :)
 
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