Wiring N Gauge Electrofrog Points

[IanWV]

I am currently wiring my n gauge layout on which I've used Peco streamline Code 55 track with electrofrog points and Cobalt ADS 2fx decoders.

 

Wiring the power supply to track went well. Everything worked with no shorts so I believe that I've placed insulating connectors and track feeds in the right places. The point operation also works well too....all the points operate as planned again with no problems shorting.

 

HOWEVER, for each of the points I have soldered a drop wire from the frog and connected it to the central input on the frog power section of the decoder. I have then run a wire from each of the live and return terminals on the decoder.....but when I attach them to the bus wire I get a short.....sometimes! There seems no rhyme nor reason to why this happens sometimes and not at others, and this is driving me nuts.

 

Any obvious answers? Have I done anything fundamentally wrong?

 

Ian

[dhjgreen]

You have modified the points for external frog switching, otherwise the blade switching will cause the shorts?

[PaulCheffus]

You have modified the points for external frog switching, otherwise the blade switching will cause the shorts?

Hi

 

There is absolutely no need to modify Peco code 55 points they work perfectly well straight from the box.

 

To the OP have you added insulated rail joins to the ends of the frog rails?

 

Cheers

 

Paul

Edited November 12, 2016 by PaulCheffus

[IanWV]

Hi

There is absolutely no need to modify Peco code 55 points they work perfectly well straight from the box.

To the OP have you added insulated rail joins to the ends of the frog rails?

Cheers

Paul

Thanks Paul, yes, have used insulated rail joints throughout on all frogs, I even sent a plan to Peco technical bureau who came back with detailed advice too. My understanding too was that there was no need to modify points.

 

As I say no problem with DCC power to tracks which I assume means insulated joiners are in right places???

 

Ian

[roundhouse]

All mine have been modified after the tie bars started melting on a number of Peco turnouts in the fiddleyard. I think it was the SEEP solenoids built in switch changing polarity a millisecond or two before or after the blades switched but not tripping the DCC

 

It seems that many don't have this problem but it's certainly made a difference on Banbury and Santa Barbara.

[dhjgreen]

Hi

There is absolutely no need to modify Peco code 55 points they work perfectly well straight from the box.

To the OP have you added insulated rail joins to the ends of the frog rails?

Cheers

Paul

You are quite correct, however the OP has added external frog switching to the points which will conflict with the automatic switching by the blades. That is my point, if you want to use extenal frog switching you then need to modify the points. Some people like to do this in the view that it improves reliability (I express no opinion).

[PaulCheffus]

You are quite correct, however the OP has added external frog switching to the points which will conflict with the automatic switching by the blades. That is my point, if you want to use extenal frog switching you then need to modify the points. Some people like to do this in the view that it improves reliability (I express no opinion).

Hi

 

No you don't. I have sixty Peco code 55 points all with frog switching which are not modified in anyway.

 

Cheers

 

Paul

[PaulCheffus]

Thanks Paul, yes, have used insulated rail joints throughout on all frogs, I even sent a plan to Peco technical bureau who came back with detailed advice too. My understanding too was that there was no need to modify points.

As I say no problem with DCC power to tracks which I assume means insulated joiners are in right places???

Ian

Hi

 

There is no real difference between wiring for DC and DCC other than possibly the thickness of the bus wires. People have in the past just disconnected their DC controller and connected their DCC system.

 

If the insulated rail joiners are in the correct place for DC then they will be right for DCC. I think your issue relates to the switch on the seep point motor as the contacts may not be far enough apart for the smaller throw on n gauge points. Personally I use the Peco point motors with their microswitches.

 

Cheers

 

Paul

[lilchris]

I am using N-Gauge code 55 and I have not modified the points apart from connecting the frog to the Switch on my Cobalt motors and supplying a feed to the toe end of the point. I did initially start with Peco motors and switches but found them un-reliable, that is why I changed to the Cobalts. They are more reliable than relying on blade contact that is certain.

[Izzy]

As the OP is using decoders with the cobalts, maybe, just maybe, there is a conflict between the cobalts and the points as regards point/frog settings since the question seems to involve initial setting up rather than this happening in actual use, if I understand the original post correctly. Could it be that the point sits one way, but the cobalt/decoder is set the other. Does that make any sense? Could that be the issue? It's just a thought as I don't use DCC for point control myself but reading the post the frog feed seems to be connected to the decoder and not directly to the cobalt.

 

cheers,

 

Izzy

[PaulCheffus]

Hi

 

Looking at the design of the cobalt its quite possible that the throw of the motor when attached to a n gauge point is not sufficient to clear the internal switch contacts. That maybe the cause of the issue here and modifying the points is not going to fix that as the polarity will still be incorrect when the loco hits the points.

 

I had similar problems with the servo driven points on my 2mm layout. The points on this layout are built with the frog completely isolated due to the small clearances between the switch rail and the stock rails. I found that I had to very carefully adjust the microswitches on each motor to ensure they switched correctly. When I build my next 2mm layout I will not be directly driving the points but using an omega loop between the servo and the point to overcome this issue.

 

Cheers

 

Paul

[Nigelcliffe]

I am currently wiring my n gauge layout on which I've used Peco streamline Code 55 track with electrofrog points and Cobalt ADS 2fx decoders.

 

Wiring the power supply to track went well. Everything worked with no shorts so I believe that I've placed insulating connectors and track feeds in the right places. The point operation also works well too....all the points operate as planned again with no problems shorting.

 

HOWEVER, for each of the points I have soldered a drop wire from the frog and connected it to the central input on the frog power section of the decoder. I have then run a wire from each of the live and return terminals on the decoder.....but when I attach them to the bus wire I get a short.....sometimes! There seems no rhyme nor reason to why this happens sometimes and not at others, and this is driving me nuts.

 

Any obvious answers? Have I done anything fundamentally wrong?

 

Ian

 

I think there is a fundamental error. 

 

 

If the Peco point is used, without modification, then it is also designed to NOT have a frog feed.  The frog is powered from the blades, which is how Peco intended it to work.

 

If a frog feed is added, then there is a potential short path:   if the switch for the frog moves at a different speed to the blades, then a short can occur (*).  Clearly if the frog feed switch is the wrong way round, then there will always be a short.    

If the switch "breaks" as the blade starts to move away from the fixed rail, stays "no connection" during most of the blade movement, and then "makes" as the blade reaches the other fixed rail, then things will work.  Which, I think, is why some people find the arrangement does work.    Or, perhaps their system is robust against the shorts which clear rapidly as the blade and switch move (though it will be causing arcing on the backs of the blades). 

 

So, what I think is happening, is that there is a difference in switching speed between the turnout motor and the polarity switch in the ADS 2FX decoder.  So, sometimes the blade hasn't quite moved at the same time as the frog switch changes.  Result a short circuit.  

 

 

Solution is to either find a different hardware which switches at a different speed (those with switches attached to the movement of the motor are more likely to work "in time" with blade movement).   Or, to modify the electrofrog turnouts so they are like classical hand-made turnouts:  the frog is isolated from the blades, and the blades are hard-wired to their respective fixed rails.   Or, to not attempt to power the frog with its own feed, and use the turnouts as Peco intended.  

 

 

 

(* oddly, this is a case where Frog Juicer solutions will work fine, because they will automatically swap with the blade contact.  But, I still maintain that there are better solutions than adopting Frog Juicers  ). 

 

 

- Nigel

[Mark Pelham]

I think there is a fundamental error. 

 

 

If the Peco point is used, without modification, then it is also designed to NOT have a frog feed.  The frog is powered from the blades, which is how Peco intended it to work.

 

If a frog feed is added, then there is a potential short path:   if the switch for the frog moves at a different speed to the blades, then a short can occur (*).  Clearly if the frog feed switch is the wrong way round, then there will always be a short.    

If the switch "breaks" as the blade starts to move away from the fixed rail, stays "no connection" during most of the blade movement, and then "makes" as the blade reaches the other fixed rail, then things will work.  Which, I think, is why some people find the arrangement does work.    Or, perhaps their system is robust against the shorts which clear rapidly as the blade and switch move (though it will be causing arcing on the backs of the blades). 

 

So, what I think is happening, is that there is a difference in switching speed between the turnout motor and the polarity switch in the ADS 2FX decoder.  So, sometimes the blade hasn't quite moved at the same time as the frog switch changes.  Result a short circuit.  

 

 

Solution is to either find a different hardware which switches at a different speed (those with switches attached to the movement of the motor are more likely to work "in time" with blade movement).   Or, to modify the electrofrog turnouts so they are like classical hand-made turnouts:  the frog is isolated from the blades, and the blades are hard-wired to their respective fixed rails.   Or, to not attempt to power the frog with its own feed, and use the turnouts as Peco intended.  

 

 

 

(* oddly, this is a case where Frog Juicer solutions will work fine, because they will automatically swap with the blade contact.  But, I still maintain that there are better solutions than adopting Frog Juicers  ). 

 

 

- Nigel

 

I can agree with Nigel, having had first hand experience of this on a third party layout. The owner had purchased the Traintronics DCC turnout motor; very similar in principle to the Cobalt DCC motors.

 

The biggest problem arises when you use the track bus to power the turnout motors in that a short on the track bus prevents the motor from throwing back to clear the short.

 

Either way, as Nigel says, if the switch blades are powering the frog, as well as an external switch; if the switch blades move to the opposite stock rail before the frog switch contact changes over, you get a short circuit. Similarly if the frog contact changes over before the switch blades start to move, you get the same.

 

In your configuration, to avoid a short you are relying on the switch blades breaking contact with the first stock rail, the external switch changing over, then the switch blades making contact with the other stock rail.

 

Cheers,

 

Mark

[IanWV]

Thanks for all the help, particularly the last two comments which rally make sense.

 

I think that what you're saying is that trying to send power from the decoder to the live electrofrog runs a high risk of shorting because of the timing of the switching vs the timing of the blade movement.

 

Do I read that the only solution is to do without the frog polarity wiring and really on switch blade contact?

 

If so, any hints on how to improve this contact.....some of my points seem very prone to pore contact.

 

Thanks,

 

Ian

[Nigelcliffe]

Thanks for all the help, particularly the last two comments which rally make sense.

 

I think that what you're saying is that trying to send power from the decoder to the live electrofrog runs a high risk of shorting because of the timing of the switching vs the timing of the blade movement.

 

Do I read that the only solution is to do without the frog polarity wiring and really on switch blade contact?

 

 

Not the only way,  I gave several solutions: 

1 - don't use frog polarity wiring and rely on blade contact  (which means cleaning the blades so they make good contact, including any little tabs at the bottom of blades which might contact below the rail.  If you can't clean them, its possible that contact cleaner spray may help). 

2 - modify the turnouts so they are wired as a classical hand-built live frog, separating the blade from the frog area, and then connecting the blade to the fixed rails

3 - electronics and use frog juicers  (I don't like them, but this case they will work).   Or the cheaper device which I think Gaugemaster have recently launched which does the same thing, but uses cheaper relay switching. 

4 - fit frog crossing switches which are synchronised with blade movement. 

 

And I can think of a few more:

 

Logically from my answer, there is 5 - some circuit which determines the turnout is about to move (from the decoder instruction), so disconnects the frog, and then re-makes the frog circuit after the blades have had time to move properly. 

 

6 -  if you have a separate bus feed available which only feeds the frog switches, then fit that with a power cut-out unit which will trip at a short, and then self-reset.   So, during any turnout blade movement, you risk all frogs on the layout going "dead" due to the cut-out tripping, but that should only be for a second or so whilst the blade moves on one turnout. 

 

And, there's always 7 - throw away the Peco turnouts and build better ones :-)

[lilchris]

Like I said in my previous post, I am using live frog points with no mods apart from a wire to the frog which goes to one of the inbuilt switches on the Cobalt motor they have been very reliable in operation with no problems with timing. I am on dcc but my point motors are controlled from a panel on a separate feed supply. I do have one Cobalt IP digital motor which can be controlled by dcc or by a push to make switch and that point frog is wired the same way with no problems whatsoever.

 

Here is a pic of how my points are wired

Edited November 17, 2016 by lilchris

[dhjgreen]

Like I said in my previous post, I am using live frog points with no mods apart from a wire to the frog which goes to one of the inbuilt switches on the Cobalt motor they have been very reliable in operation with no problems with timing. I am on dcc but my point motors are controlled from a panel on a separate feed supply. I do have one Cobalt IP digital motor which can be controlled by dcc or by a push to make switch and that point frog is wired the same way with no problems whatsoever.

 

Here is a pic of how my points are wired

DSCF4762 640x480.JPG

A number of people advocating this approach seem to be missing the point that the OP is having a problem with shorting. Your good luck with getting away with double wiring is not really helpful to him.

[PaulCheffus]

A number of people advocating this approach seem to be missing the point that the OP is having a problem with shorting. Your good luck with getting away with double wiring is not really helpful to him.

Hi

 

However it proves that the system can be made to work.

 

Cheers

 

Paul

[2mil Graham]

Hi

I had a similar problem recently - unmodified Peco points with feeds to Cobalt motors. Only some of the points produced a short-circuit, and only in one direction.

As others have suggested, I suspected the blade movement was out of sync with the point motor switch. Removing the springs in the points solved the problem.

 

Graham

[lilchris]

Perhaps I should have added I did remove the spring on the points fitted with Cobalts has reccomended by the manufactorer, adding the wire to the frog is not double wiring it supplies a feed to the frog direct so you do not have to rely on contact with the switch blade. You could do has Nigel says and cut the link on the switch blades and connect them to the next rail as per oo gauge, but if you are not carefull you could destroy the point because they are so small. My points on my fiddle yard for instance are insulfrog code 80 points from a old layout, I constantly have to keep cleaning the switch blades. 

[Nigelcliffe]

Perhaps I should have added I did remove the spring on the points fitted with Cobalts has reccomended by the manufactorer, adding the wire to the frog is not double wiring it supplies a feed to the frog direct so you do not have to rely on contact with the switch blade.

 

Yes it is "double wiring", or more accurately, "a potential short circuit".    Only if the switch movement in the Cobalt is in line with the movement of the blades on the turnout is the short avoided.   Fortunately, with most motors, the switch is aligned with the motor movement, so the short doesn't occur.  But the potential for a short is still present.   In practise many modellers never find the short happening, so its probably a workable solution.    

[lilchris]

Thank you Nigel for your input, I understand what you are saying about a potential short, but at the end of the day Peco Slips and Diamond crossings come pre-wired that way when you buy them new, so how are you supposed to wire those.  Like you say has long as you use a reliable switching there is not a problem, I initially used Peco motors and switches and they were un-reliable switching, that is why I changed to Cobalt motors and they have proved reliable.

By the way when I used the peco motors and switches, after finding them un relaible I started to use a Hex Frog juicer to work the frogs and was told that was the wrong way to do it but it worked fine,  I eventually changed to using  the Cobalt motor switches for most of my points.

Edited November 21, 2016 by lilchris

[Nigelcliffe]

Thank you Nigel for your input, I understand what you are saying about a potential short, but at the end of the day Peco Slips and Diamond crossings come pre-wired that way when you buy them new, so how are you supposed to wire those.

I don't have examples of either to check the continuity through all rails without external switches.

However, the diamond with live-frog cannot be switched by blade movement because there are no blades. So, with a live frog, Peco would have to provide wires for an external switching arrangement, and would also have to provide gaps in the rails to insulate the frog from the fixed rails (or the diamond would be a complete short when it was installed). The slip would appear to be similar to the diamond, there is no way to pre-wire them for all combinations using just blade switching.

So, in this case, it appears that the ordinary turnout is the "odd ball", where Peco have realised that they can by-pass the electrical gap between blade and crossing, and then use the blade to switch the frog power. The blades moves a long way when open, so back of an N wheel that's within specification cannot short to the open blade.  This removes the need for external electrical switches.  From Peco's perspective, this makes the product a lot simpler to install for the average modeller.   

But, it relies on the blades being clean (which is often not the case after track ballasting and painting) and the turnout not being slightly twisted in installation (which can stop the blade contacting), so many modellers don't find this blade switching to be reliable. 

Hence we get to either "taking a chance" on the blade and external switch being synchronised in movement, or "hacking the turnouts" by creating extra insulation gaps and adding blade bonding wires. 

[ColinK]

Restarting this topic. A friend has started building his first layout and has asked me to help with the wiring. While I know how to wire up 00 gauge, his layout is N gauge of which I have little experience. He is going to use Peco electrofrog points and DC power.

 

So, do we just lay the points as they come out of the box and not use any form of frog polarity switching?

 

Or do the N gauge points have to be modified (as I've done on my OO layout) and frog polarity switching added.

 

I do know the importance of only feeding power from the toe end. The points will be manually worked by rodding. It is a home layout with no plans for exhibiting it.

[PaulCheffus]

Restarting this topic. A friend has started building his first layout and has asked me to help with the wiring. While I know how to wire up 00 gauge, his layout is N gauge of which I have little experience. He is going to use Peco electrofrog points and DC power.

 

So, do we just lay the points as they come out of the box and not use any form of frog polarity switching?

 

Or do the N gauge points have to be modified (as I've done on my OO layout) and frog polarity switching added.

 

I do know the importance of only feeding power from the toe end. The points will be manually worked by rodding. It is a home layout with no plans for exhibiting it.

Hi

 

I've never modified any of my sixty Peco N gauge points and also use frog polarity switching without issue on a layout that is now twelve years old. Points are controlled by Peco PL10 point motors with PL15 microswitches for the frog switching.

 

Cheers

 

Paul