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Discussion Starter · #1 ·
I'm getting a bit confused about how to connect electrofrog turnouts in to a DCC layout at the simplest level. If I've understood things correctly, all one needs to do is to insulate the two rails that form the frog from the rest of the turnout. And by doing so, aren't you effectively creating an insulated frog?

I've tried reading the Wiring for DCC site, and to be honest, I have a feeling that it's overcomplicating things.

Thanks,

Dave.
 

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I don't have a drawing of how the electricity flows in a two way point for each of its settings but I do have one for a 3 way asymmetric one, which I offer here just in case it helps. It is colour coded, so maybe it will.

The point with electrofrog points is that there is a lot more metal to provide contact with the loco wheels so you have a much better chance of maintaining contact and more often. The downside is that you need to switch the polarity of the frog. As delivered, Peco points do this using the point blades. Over time this can become unreliable so some people prefer to use a micro switch controlled by the point motor. For the 3 way assymetric point, as far as I know, you don't have a choice, you have to use switches which is why I created this drawing for my own use.

Print it out, ignore one of the crossings completely and it you stare at it for long enough, the penny may drop.

Enough rambling from me, here's the pic:-
Slope Font Parallel Circuit component Pattern

David
 

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Discussion Starter · #3 ·
David,

Thanks for the reply
.

That's quite some diagram! I'll have to have a really good look to see if I can figure it all out.

However, let's assume that it's operating in an ideal situation, and the contact of the point blades don't become less reliable, is what I said true, i.e. at the simplest level, all you need to do is isolate the frog rails from the rest of the track? I'm not disagreeing with you, in fact I've read several sites that describe what you have, but I've also read a couple of sites that say that you don't need to do extra work on the points. Just trying to get to the bottom of it all
.

Thanks,

Dave.
 

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Hi digitaldave.
My site my offer some guidance on points? It's a bit long, so look through then read it and you may understand.
Here's the link....Points and all about them
As DWB has said, Live frog or Electrofrog as Peco call them, is really about the ability to be able to run locos really slowly over the frog part of the point without the loco stalling on a insulated frog (crossing).
All the best and good luck
 

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There are fudges and fixes possible, but the best approach is to get it right...

You need to isolate the frog, electrified it seperately through a feed switched in connection with the lie of the point blades/route and dispense with the contact between the switch rails and the stock rails.

On modern Peco electrofrog points you will find two little links underneath the point blades. For DCC these must be broken with a small screwdriver. This then leaves the frog completely isolated , and the point blades divided in two electrically. You bond the section of the point blades
AWAY from the frog to the adjacent stock rail (outside running rail) so it is perminently fed from this rail , and therefore live at the same polarity. This ensures there can be no short circuit between point blade and stock rail. To bond across , the normal trick it to take a short length of bared and twisted wire and solder it across the two rails underneath

The frog is now completely isolated - but on Peco you will find there is a length of wire underneath , soldered to the frog. This should be connected to a switch, to which are connected a feed to each traction bus bar (conventionally red and black). Peco sell a suitable switch that fits on top of their point motors ; Tortoise point motors have a switch built inside and apprpriate contacts outside. In both cases the manufacturers instruction leaflet explains what you are supposed to do

This means the polarity of the frog will now be switched automatically by the operation of the point motor.

This is the normal way handbuilt pointwork is wired , and definitely best practice for DC though you can get away without it on DC

QUOTE but I've also read a couple of sites that say that you don't need to do extra work on the points

Er yes..... This generally means someone is bodging their wiring in such a way as to disable/render ineffective the short circuit protection in the command station.

For obvious reasons this approach - "If your points cause shorts that would trip the short circuit protection , wire your layout so the short circuit protection doesn't work any more. Then shorts won't stop your layout..." is highly undesirable. I'm not even going to hint how you disable short circuit protection......
 

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QUOTE I'm getting a bit confused about how to connect electrofrog turnouts in to a DCC layout at the simplest level

At a basic level (provided your prepared to possibly lift and modify later) you can lay Peco Electrofrogs straight out of the box with an insulated joiner on the two inner most tracks that exiting the frog. OK it's not a perfect solution, and as turnouts wear they might play up a bit. Peco turnouts are DCC friendly, so if you want to get started with the minimum of fuss just lay out of the box. On my original DCC layout I had over 120 Peco turnouts and 8 double slips, used as I bought them out of the box with no modification, and there were very few problems with five years of intensive use. I recall one turnout that needed replacement which is an excellent record. Adding polarity switching will add £5.00 for the switch to the cost of every turnout. At these prices you can afford to ignore polarity switching for a bit and buy a few more turnouts. I must add that my two current layouts under various stages of construction will feature polarity switching.
 

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I read all the above with great interest.

I've built 3 or 4 railways in the last 18 years in n and OO all with electrofrog points. I'm no technician but did work out enough to wire feeds to them all from the sharp end, and put insulated joiners on all four rails at the other end. I didn't do anything else and relied on the point blade to conduct electricity through to the frog.

This worked with only very occasional failures, and in the case of the n gauge railway 30+ sets of points worked like this for 17 years, and were still working when I dismantled it last summer. I was proposing to reuse some of the points on the next railway.

So now I'm feeling rather foolish and concerned. Was I just lucky? I'm a bit daunted at the modifications set out on the website linked above. I think I'd need to see this in real life somewhere. Anyone live in East Anglia?
 

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Discussion Starter · #10 ·
Jonathan,

From what I've managed to glean from my reading around, the setup you have been using is the simplest option, and will work. However, I believe that the modifications that others have mentioned are designed to increase the reliability. But I believe that the modifications do not need to be done. I'm sure someone will correct me if I'm wrong, but that's how I see it from what I've been reading.

Regards,

Dave.
 

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>But I believe that the modifications do not need to be done
You are quite correct - there is no need to them to be done.

In my case I have been influenced by the experience of having a duff connection on a set of points that had been unused and left in the attic air for about 10 years. The dodgy connection drove me nuts, so I have decided to take all possible precautions as I lay new track. It's a personal choice.

David
 

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QUOTE On modern Peco electrofrog points you will find two little links underneath the point blades. For DCC these must be broken with a small screwdriver. This then leaves the frog completely isolated , and the point blades divided in two electrically. You bond the section of the point blades
I believe this only applies to Peco code 75 points. I haven't seen a code 100 point with this feature as yet!
DWB is quite correct, you don't need to do anything to live frog points other than ensure the two frog exit rails are insulated at some place after the frog (Normally and most easily done in the rail joint immediately after the point).
You can rely solely on the switch blades making contact to the stock rails to feed power into the frog. However this can eventually lead to poor electrical connections and its far better to use a micro switch driven by the point motor to supplement the power to the frog and ensure reliable frog power supplies. Further works such as cutting the closure rails etc or removing the factory fitted link (Code 75 points) and commoning the adjacent switch and stock rails is a further enhancement, but again not really necessary if you don't wish to do it.
 

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QUOTE its far better to use a micro switch driven by the point motor to supplement the power to the frog and ensure reliable frog power supplies. Further works such as cutting the closure rails etc or removing the factory fitted link (Code 75 points) and commoning the adjacent switch and stock rails is a further enhancement

I have a suspicion, unfounded, that if you use a micro switch to control the frog polarity and do not remove the link, you run the danger of momentary shorts between the power rails, as it is probably nigh on impossible to guarantee that the switch blade and the micro switch will change simultaneously. This is not a problem for DC operations, but on DCC it might be long enough to trip the short circuit detection. I am acting on the precautionary principle of removing the links and bonding the switch blade rails to the outer edges when I install micro switches along with the point motors.

David
 

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QUOTE (digitaldave @ 11 May 2007, 04:09) <{POST_SNAPBACK}>Jonathan,

From what I've managed to glean from my reading around, the setup you have been using is the simplest option, and will work. However, I believe that the modifications that others have mentioned are designed to increase the reliability. But I believe that the modifications do not need to be done. I'm sure someone will correct me if I'm wrong, but that's how I see it from what I've been reading.

Regards,

Dave.

Jonathan,

You most definately NEED to make the modifications indicated on our page http://mrol.gppsoftware.com/livefrogwiring.asp (Thanks Chirkwood for posting it).
If you want to avoid all possible opportunities for shorting, the above link describes the ONLY way to wire live frog turnouts. It is the same technique used on hand-made track and applies equally to code 75 and code 100. The difference is that with code 100, you need to cut rails whereas on code 75, it is done for you.
I acknowlegde that it is not so easy to implement in smaller scales such as N and Z.

There are many people who go around 'dumbing down' live frog turnouts and saying that you don't need to wire them properly. DONT'T BELIEVE THEM! THEY ARE WRONG! They will all tell you that they get periodic problems! That proves the point - it doesn't work reliably if you don't do it properly!
If you don't break the switch rails and bond the switch blades to the stock rails, you will get shorting between the stock rails and switch blades. This becomes particularly noticeable in DCC with its superior short protection.

Some people will say that gauging wheels means they don't have problems. That maybe so, but it is better to fix the problem which is creating the possibility of a short (ie turnout wiring) than using a solution which is wide open to a problem and is guaranteed to fail at some point in time.

Graham Plowman
 

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QUOTE (dwb @ 11 May 2007, 07:36) <{POST_SNAPBACK}>I have a suspicion, unfounded, that if you use a micro switch to control the frog polarity and do not remove the link, you run the danger of momentary shorts between the power rails, as it is probably nigh on impossible to guarantee that the switch blade and the micro switch will change simultaneously. This is not a problem for DC operations, but on DCC it might be long enough to trip the short circuit detection. I am acting on the precautionary principle of removing the links and bonding the switch blade rails to the outer edges when I install micro switches along with the point motors.

David

dwb,

Your are exactly correct on all points above. Your approach is the correct way to go!

Graham Plowman
 

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Graham & I may not agree on some aspects of DC vs DCC but I will agree with him on the modifications to points not only for DCC but DC as well.


Relying on blade contact for power routing may work all the time for you but Sod's law (or whatever you want to call it) will say the first time you show your layout to someone else, power will fail beyond a point or two.

Yes, it does take a bit of time & a bit more wiring but the hobby is just that, a hobby, no need to be in a hurry to get it finished; enjoy all the facets of building your Railway empire.
 

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QUOTE I'm getting a bit confused about how to connect electrofrog turnouts in to a DCC layout at the simplest level. If I've understood things correctly, all one needs to do is to insulate the two rails that form the frog from the rest of the turnout. And by doing so, aren't you effectively creating an insulated frog?

While I agree with everyone with regard to polarity switching. Digitaldave just wanted the simplest method, and in that regard he can simply rely on the turnout blade and lay his Peco Electrofrog turnouts straight out of the box. I repeat Peco turnouts are DCC friendly. I think the most important thing for folks just starting out in DCC is to get something running as quickly as possible. It's normally no big deal to lift turnouts and do the modification at a later stages before you ballast.
 

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QUOTE Digitaldave just wanted the simplest method, and in that regard he can simply rely on the turnout blade and lay his Peco Electrofrog turnouts straight out of the box

Here Here MMAD
Pity some have to go off at tangents and possibly confuse/frighten/ bewilder the novice!

QUOTE There are many people who go around 'dumbing down' live frog turnouts and saying that you don't need to wire them properly. DONT'T BELIEVE THEM! THEY ARE WRONG! They will all tell you that they get periodic problems! That proves the point - it doesn't work reliably if you don't do it properly

I don't think anyone has said this??? What has been stated, to a novice, is Its not essential. the points WILL work without any modifications straight from the box! What has been said is.... 'TO IMPROVE PERFORMANCE' then do..... etc.

Cutting the closure rails on a code 100 point and fitting some form of insulated insert into the slit to prevent the two haves of rails touching again and then cutting away a piece of underside webbing and soldering on two wires linking the adjacent switch and stock rails isn't one of the easiest jobs for a novice to undertake! Simple frog switching from a point motor operated switch is perhaps a little easier but still a little advanced for a novice!

I think were agreeing on the final choice of preferred working, but remember the original question came from someone who's own words were "I'm getting a bit confused about how to connect electrofrog turnouts in to a DCC layout at the simplest level."
 

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I am building a layout that has been 20 years in the planning .When I reached the point where I needed to wire the layout I was totally confused how to proceed.Through this forum I have received much advice ,in particular from Graham Plowman & Brian Lambert
They encouraged me to do it THE right way.Having hardly ever used a soldering iron I am now something of an expert after spending several weeks modifying and wiring turnouts. My initial test running has shown no problems with "shorting".My advice is if I can do this so can anyone , so if you can spare the time have a go it's not as daunting as it first appears
Keith
 

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QUOTE (Brian @ 11 May 2007, 23:12) <{POST_SNAPBACK}>Here Here MMAD
Pity some have to go off at tangents and possibly confuse/frighten/ bewilder the novice!
I don't think anyone has said this??? What has been stated, to a novice, is Its not essential. the points WILL work without any modifications straight from the box! What has been said is.... 'TO IMPROVE PERFORMANCE' then do..... etc.

Cutting the closure rails on a code 100 point and fitting some form of insulated insert into the slit to prevent the two haves of rails touching again and then cutting away a piece of underside webbing and soldering on two wires linking the adjacent switch and stock rails isn't one of the easiest jobs for a novice to undertake! Simple frog switching from a point motor operated switch is perhaps a little easier but still a little advanced for a novice!

I think were agreeing on the final choice of preferred working, but remember the original question came from someone who's own words were "I'm getting a bit confused about how to connect electrofrog turnouts in to a DCC layout at the simplest level."


All the time I give people the best possible advice so that they can get total reliability, we get people coming along saying 'oh, he's only a novice, it doesn't matter, he just wants to get things running' and then we get this nonsense about confusing, frightening people off, bewildering and making things to hard for them!

What right do we have to assume their relative capabilities ? Why should a 'novice' be given advice which is anything less than the best ? Aren't they entitled to get it right first time ? Aren't they entitled to learn the correct ways and be helped ?

There are already two messages in this thread which demonstrate eactly the point I was making about 'dumbing down'! In my opinion, a 'novice' should be given the same best possible advice as anyone else so that they can get the best reliability from their investment in the hobby. It is not up to us to provide them with a compromised solution based on the assumption that things need to be dumbed down to suite their abilities. Don't assume that they can't learn!

Graham Plowman
 
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