sparking/electrical problem with Peco points

snipped-for-privacy@gppsoftware.com wrote:


Sure, but I place the isolating fishplates where-ever they should logically go, which is not neccessarily on the turnout.
Greg.P.
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snipped-for-privacy@gppsoftware.com wrote:

Ok, ok, pedantics - if the poster didn't have an interest in the hobby he wouldn't have a problem!

It wasn't!
then I assume DC is

Why is the short momentary?
This is one of the problems people blame DCC for because it has a

Yeah yeah, we weren't discussing DCC.

Those are the ones - they are on all HO turnouts that I've looked closely at.
and they certainly don't always misbehave without them.
True, but they are put there for the purpose of maintaining contact when the turnouts get a little dirty, as all turnouts on operating layouts do. You've got about 6 months trouble free operation from new without them.
So how

Yes, but the turnouts only work reliably until the sides of the point blade and stock rail tarnish sufficiently to impede current flow. Put a tiny speck of dust between the two and you get current jumping the tink gap causing sparks.
The turnouts will work without them, but I

Well, from my point of view you've just destroyed one of the best features of Peco turnouts, the automatic current switching.

No!!! If the problem is a miswired live frog turnout then the short will be more than momentary.

Not entirely - the turnout is probably a dead frog turnout and the symptom of sparking is in all likelyhood the cause if it is a dead frog turnout.

Certainly. However, we don't neccessarily have a short. In fact we probably haven't got a short.
however, if the problem is a short, evidently the turnout

Very true, but so far we haven't got a short - you made that up.
- a case for checking wheel standards and back-to-backs.

Agreed, but Peco have covered that point by adding sliding sprung contacts.
All switching should be done

Agreed, but Peco have covered that point by adding sliding sprung contacts, fragile ones admittedly but otherwise reliable over long periods of operation.
And

No - the dead frog and current passing between stock rail and point blade matches the description whereas a direct short does not.
the only way to stop it is

That will NOT fix the problem of damaged point blade contacts, assuming that is the problem. That alteration only provides extra expense and disruption.

Agreed :-)
Regards, Greg.P.
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Greg,

Because Elliot described a spark as being observed - which is what happens when a passing short occurs. If it was a long term short (which it wasn't) then the controller would cut out.

Evidently you've only seen code 100 turnouts. None of the code 75 turnouts have them - I know this for a fact because my present layout is full of code 75 in the visible area and has 16 code 100 in the fiddle yard. And Nor do the 009 IIRC. Don't know about code 83. One could argue that all of the 16.5mm gauge turnouts are HO!

the turnouts get a little dirty, as all turnouts on operating layouts do. You've got about 6 months trouble free operation from new without them.
Which is what I said! But as I also said, Peco don't put them on all of their turnouts - have a look at their other ranges.

blade and stock rail tarnish sufficiently to impede current flow.
Which is also what I said!

tiny speck of dust between the two and you get current jumping the tink
gap causing sparks.
Can't say I've ever seen this unless an HF track 'cleaner' is connected.

features of Peco turnouts, the automatic current switching.
Since I mostly use live frogs, I always have switches involved and in my DC days, I always separately fed sidings as isolating sections....which made conversion of the layout to DCC a lot quicker. Relying on turnouts to switch sidings on/off in my view is not good practice. Most layouts I have seen doing this have ended up having electrical problems, especially when live frogs were also in use. Don't forget, even the tabs are not perfect either - I've had several of them fail in the past - that is why I use live frog now (among other reasons).

Greg, do you actually have experience of wiring live frog turnouts ? My layout is full of them, so I know what I'm talking about. If a live frog is not wired properly, it is possible to run out-of-gauge/B2B wheels through the gap between the switch blades and stock rails and get a momentary short, observed by a spark. I have seen this on so many club layouts that I have forgotten how many times I've seen it! I can assure you that as the train passes, it is a momentary short and it certainly isn't enough to trip the cut out on a DC controller. In fact, I have heard people describe it in exactly the same terms as Elliot has done.

symptom of sparking is in all likelyhood the cause if it is a dead frog
turnout.
Sparking is not a cause. It is the result of an electrical fault.

got a short.
We've either got a short or lost contact. Not sure that we have enough info as yet to confirm one way or the other, but a dead-frog does tend to suggest a lost contact.

Elliot presented a situation which to me and a few others on this list had all the hallmarks of a short. It may be, it may not be. My experience has been that sparking is usually a result of shorting because the voltages and currents we are dealing with are not enough to cause significant sparking unless the track is really dirty. The fact that Elliot described the short as appearing on the tips of switch blades was really a tell-tail. I suppose we do need a confirmation as to whether the spark occurs between the stock rail and switch rail when they are touching or when they are not touching ie being bridged by a wheel.

contacts.
I think I didn't explain properly. I meant that my personal opinion is that turnouts should not be used as the means of isolating sidings. Sidings should be separately fed using an isolating section so as not to rely on the turnout or its switching. The tabs are really irrelevant - I don't wire isolating sections because of the relibility of turnouts - I do it because (especially with live frog) switching turnouts invariably causes shorts due to unexpected circuits being made - I've seen too many clubs fall into that trap. Of course, with DCC, I don't have any of these issues. I simply power every section of track all the time and make sure my turnouts are not back-fed via the use of insulated joints - life is so much easier!

that is the problem.
True - insulated joint won't fix that problem. Probably should use a meter to get an idea of the currents involved.

Really, all of these problems can be resolved by using sound electrical wiring principals and practices in the first place. The trouble is, electrical systems are considered by many as some unnecessary evil and added as an afterthought instead of a properly intergated part of a layout and installed at track laying time. I don't have any of these problems on my layout.
Suggest we wait for input from Elliot.
Graham Plowman
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snipped-for-privacy@gppsoftware.com wrote:

Without going back to the initial post to check the precise original wording, I think "sparking" was described - this could be either shorting or current across a poor connection. As it was a dead frog turnout being described ...

I use both Code 75 and code 100, the Code 100 for the last 30 years.
None of the code 75

You got me there - I guess I just assumed there were contacts on my Code 75s. <ouch> And Nor do the 009 IIRC.
I only own a couple of those.

Of course they are - Peco 16.5mm gauge track has always been HO. If you Poms want to run incorrectly scaled models on it then that's entirely your own business. ;-)

So far I've only bought Code 75 turnouts when I've needed them, so I haven't studied them on the bench.

If you've got a loco drawing half an amp sitting on the track beyond the points and powered through the point/stockrail connection with dirty contact faces then of course you are going to get sparking - go check your layout!

Why?
which made conversion of the layout to DCC a lot quicker.
Why would you do that?

Why?
Most layouts I have seen doing this have ended up having

Why? The switching of the live frog is separate from the switching of the points.

I haven't had one fail in 30 years - other than from poor ballasting or fingerpoking, for which reason I will no longer buy secondhand Peco turnouts.

Yes, but I have no experience of miswired live frogs. Perhaps I run my locos slower than you but the reason I've moved to live frogs is to get locos across them at scale shunting speeds without stalling. (0-4-0Ts, 2-4-0s etc)
My

True, but neither of us is sure what we are discussing. ;-)

I agree - the bit I'm arguing is your assumption that live frog turnouts are involved when Elliot specifically said he thought the turnouts were dead frog.

I said "... symptom of sparking ..."

I'm interested here for my own purposes! I've been using the isolating feature of Peco turnouts for the last 28 years without problems. Admittedly that's 6 or so layouts and few if any turnouts would have lasted that long.

Why? Using the Peco isolating feature along with other subterfuges has almost allowed me to eliminate isolating switches entirely.
The tabs are really irrelevant
I disagree based on my experiences.

I agree - I have very few electrical problems, and those mostly stem from turnout failure.

I imagine we've frightened him off! =8^)
Regards, Greg.P.
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Greg,

points and powered through the point/stockrail connection with dirty contact faces then of course you are going to get sparking - go check your layout!
This is a problem I just don't have because I don't rely on switch blades as the switching mechanism for exactly the sparking reason.

Because in DC days, if there was a loco already in a siding, it would spring to life when a turnout was changed unless it was separately isolated.

Because in the conversion from DC to DCC I simply connected the isolating section to the main bus and this made the siding live all the time, regardless of the turnout position and because of the insulated joints, the live frogs were already correctly protected against back feeding.

Unreliable switch blade contacts. In DC, everything springs to live in the siding when you change the turnout

The switch is usually attached to the turnout. The point I was making was that I don't believe sidings should spring to life when a turnout is changed otherwise in DC, everything in the siding springs to life. In DCC it just isn't an issue.

fingerpoking, for which reason I will no longer buy secondhand Peco turnouts.
I have.

Hmmm. But in other e-mails you ask the question about breaking the switch rails and connecting the switch blades to the stock rails. You even said you don't break the switch rails. So you do have experience of incorrectly wired live frog turnouts!

frogs is to get locos across them at scale shunting speeds without stalling. (0-4-0Ts, 2-4-0s etc)
Absolutely agree and I do the same.

Yes, but in DC you end up having this constrained operation where you have to keep locos away from each other if you don't have isolating sections and rely on turnouts to isolate them.
Graham Plowman
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On 22 Mar 2006 14:18:28 -0800, snipped-for-privacy@gppsoftware.com wrote:

This just shows bad planning, why set up the route into a siding you don't intend to run into? If you do intend to run into it then the loco will 'spring to life' when you switch the section on, so you have still the problem. Tracks where multiple locos need access need subdividing in DC setups whether the primary isolation is by the point switching or by section switches.And, as you identified, eliminating this situation is one of the joys of DCC. I eliminated the entire 20 switch panel for my small loco yard. Keith
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Keith,

don't intend to run into?
This is a simplistic view. If one has a number of sidings splaying out, in order to set the route to the required sidings, you will go through a process of selecting all the turnouts one by one to set your route. This means that it is possible to liven up sidings accidentally while setting the required route since most people will not be able to set all turnouts at exactly the same time unless they have an advanced control system. If there is no isolation, then locos can spring to life accidentally.

loco will 'spring to life' when you switch the section on, so you have still the problem.
The general rule should be to switch everything off and only switch it on when it is required. Then the changing of turnouts has no affect on activiating locos accidentally.

whether the primary isolation is by the point switching or by section switches.And, as you identified, eliminating this situation is one of the joys of DCC. I eliminated the entire 20 switch panel for my small loco yard.
Absolutely. I eliminated the need for a panel and 40 relays under DCC.
Graham
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snipped-for-privacy@gppsoftware.com wrote:

If we have a throat track with sidings running off it then the turnout settings must lead to one of the sidings. The "No siding" setting occurs when the 'main line to sidings' turnout is set for the main line. One doesn't change _that_ turnout until the rest of the route is set!!! No problem!

I eliminated around 40 block switches by using the turnout track switching function.

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snipped-for-privacy@gppsoftware.com wrote:

If you use route powering wiring methods like Peco turnouts have built in, (insulfrog or electrofrog) and provide power to the first turnout, and then power the next turnout from the frog (where appropriate) of the preceding turnout only one siding can be powered at a time, the one selected, irrespective of the position of individual switches.

There is no problem you describe because the power routing method described above only allows power to the selected track route. One reason we often see DC layouts with more than necessary switches is because popular low cost Atlas turnouts are not wired for electrical route selection and this less than ideal method is describes in many US publications about layout wiring.

If I converted my layout to DCC It would not have eliminated any relays. However all of the relays could be replaced with alternative technologies, using DCC or DC.
Terry Flynn
http://angelfire.com/clone/rail/index.html
HO wagon weight and locomotive tractive effort estimates
DC control circuit diagrams
HO scale track and wheel standards
Any scale track standard and wheel spread sheet
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Terry,

in, (insulfrog or electrofrog) and provide power to the first turnout, and then power the next turnout from the frog (where appropriate) of the preceding turnout only one siding can be powered at a time, the one
selected, irrespective of the position of individual switches.
Yes, that is true. But as I keep repeating myself, if one has a splay of sidings and some have locos in them, without isolating sections you are going to have a problem. There is going to be a time when turnouts are being changed and during that process, something springs to life when it shouldn't.
I can't put it any simpler for you guys to understand!
Graham Plowman
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snipped-for-privacy@gppsoftware.com wrote:

I have been wiring and operating DC layouts using the above method for about 30 years and never have had the problem you described unless the operator selects the wrong route. A problem that cannot be eliminated with any simple system. The only difference is with your panel you need to throw 2 switches to get a model going for a particular track, I use only one. Simpler to make and use, similar to many prototypes, and less chance of forgetting to throw the extra switch.
Terry Flynn
http://angelfire.com/clone/rail/index.html
HO wagon weight and locomotive tractive effort estimates
DC control circuit diagrams
HO scale track and wheel standards
Any scale track standard and wheel spread sheet
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Keith wrote:

I have never needed a panel with 20 switches on any of my DC layouts purely dedicated to switching power. Using route power selection, the way Peco wire their turnouts out of the box is one way of doing this which simplifies control panels. However as many have indicated in this thread under gauge wheels can cause a momentary short between the point and stock rail on electrofrog turnouts. The other problem with the out of the box wiring is it is possible to get a momentary short circuit if you feed power into the frog with a switch separate from the point motor. Usually this is not a problem if you use point motors with mechanically linked change over electrical contacts. There are 2 solutions, correctly gauge your wheels, or rewiring the turnout often described as DCC friendly wiring, though this wiring method has been around since DC 2 rail has been used. I have been wiring turnouts this way for over 20 years. It allows the point blade location and throw to be closer to scale without electrical shorting problems. I have visited and operated a number of layouts that have used Peco turnouts. Some use Peco point motors and accessory switches, others use Tortoise stall motors. No modification to the Peco turnout wiring was done on these layouts and no shorting was observed indicating Peco out of the box does not need electrical modification.
Terry Flynn
http://angelfire.com/clone/rail/index.html
HO wagon weight and locomotive tractive effort estimates
DC control circuit diagrams
HO scale track and wheel standards
Any scale track standard and wheel spread sheet
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Terry,

way Peco wire their turnouts out of the box is one way of doing this which simplifies control panels.
Yes, ONE way, but it isn't without its problems and it compromises the operation of a layout.

thread under gauge wheels can cause a momentary short between the point
and stock rail on electrofrog turnouts.
So now that we acknowledge the problem, why don't we wire to avoid it ? When there is so much information available on how to resolve this problem properly, why do people continue to deny the problem and repeatedly fill groups like this with messages about the problem ?

of the box wiring is it is possible to get a momentary short circuit if
you feed power into the frog with a switch separate from the point motor. Usually this is not a problem if you use point motors with mechanically linked change over electrical contacts. There are 2 solutions, correctly gauge your wheels, or
Agreed.

described as DCC friendly wiring, though this wiring method has been around since DC 2 rail has been used. I have been wiring turnouts this way for over 20 years. It allows the point blade location and throw to be closer to scale without electrical shorting problems.
Absolutely. There is no such thing as 'DCC friendly'. It is simply the proper way to wire a turnout and is the way anyone who has been hand building track has been doing it for several decades. It avoids all possible problems of shorting, out-of-gauge wheels etc using sound electrical wiring principals.

turnouts. Some use Peco point motors and accessory switches, others use
Tortoise stall motors. No modification to the Peco turnout wiring was done on these layouts and no shorting was observed indicating Peco out of the box does not need electrical modification.
That may well be because they are dead-frog turnouts. I don't think I have ever seen a layout with live frog turnouts incorrectly wired which hasn't had some kind of electrical shorting problem.
With DCC you simply can't get away with dodgy wiring methods: it forces you to solve the problems and wire properly otherwise the cut out keeps cutting out.
Graham Plowman
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snipped-for-privacy@gppsoftware.com wrote:

The Peco Electrofrog Turnouts out of the box work electrically because the point throw is way over scale to avoid shorting, therefore they are correctly wired if you run the correctly gauged wheels through them (around 14.4mm). Old Triang Hornby wheels would probably give trouble though. The NSW AMRA layout uses numerous Electrofrog Peco Turnouts, which have not been rewired (turn up to the open day and see for yourself). It's a non prototype specific layout and members run all sorts of wheels on this layout without electrical problems. I have actually seen more shorting from the frog area of Peco Insulfrog turnouts. Another reason to avoid Peco Insulfrog turnouts. Graham, there is more than one to wire live frog turnouts, the method you and I use is the better way to go but it is not necessary to convert Peco turnouts if you use DC and if your models are of recent manufacture they are OK for DCC as well.
Terry Flynn
http://angelfire.com/clone/rail/index.html
HO wagon weight and locomotive tractive effort estimates
DC control circuit diagrams
HO scale track and wheel standards
Any scale track standard and wheel spread sheet
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snipped-for-privacy@gppsoftware.com wrote:

OK, so you are overlooking the obvious in your supositions as to Elliot's problem.

It will do exactly the same thing if you turn on the isolating switch!

Sure, but I was asking why you would want to convert to DCC! ;-)

I've already stated i've gone thirty years without that problem - when does it start?

That surely is the whole point of changing the turnout! (or do you randomly change turnouts just for the hell of it?)

Sure, and I've had a number (5-6) Peco turnouts fail because the overcenter spring cut it's way through the adjacent sleeper. Should I be retrofitting cast iron sleepers???

I don't break the switchrail bonders and I don't have an electrical problem - what am I doing wrong??? =8^O

That is the exception to my 'no switches' block wiring. It's an awful lot cheaper than buying a DCC controller and a hundred decoders!!!
Greg.P.
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Greg,

No, I am always aware of it as an issue.

No! If a loco is parked somewhere, you switch off the isolating section. That way, if any turnouts are changed while another loco is moving, there is no risk of other locos springing to life.

I think you mean't 'wasn't'. But since you write the above, where do you want me to start ? In DC you drive the track and anything which is on it, moves. In DCC, you drive an individual loco, that loco and no other loco, irrespective of what else is on the track. This in itself is a huge benefit. All the time you are relying on turnouts to isolate locos, you have to compromise your operation in order to keep locos away from each other. Personally, I prefer a much more reallistic operation where the control system does not impose such limitations and that is one of the many reasons I use DCC. Isolation of sidings in DCC is really not recommended because loco/train lights go off as does sound (accptable in a fiddle yard, but not on the scenic section of a layout) - DCC has a constant track voltage present.

Well you are lucky. I've seen it on numerous club layouts and my very early attempts - it is fairly common.

(or do you randomly change turnouts just for the hell of it?)
Yes, you do want the siding to liven up, but what about the loco sitting at the far end of the siding - a very common operating practice ? Using your approach that loco will always spring to life...but then of course, you don't put a loco at the end of the siding in the first place because your control system compromises your operating methods so you don't do it. But this issue is resolvable in DC by using an isolating section. That way you can have two locos in the same siding and at the same time, it can stop locos springing to life when turnouts are changed. No, I don't change turnouts randomly - I use a fully computer controlled and fully interlocked system with IECC panel route setting: http://www.gppsoftware.com/ssi But don't forget, while you and I might have high standards of operation, a lot of people/clubs do not - have a look at any exhibition. Because they don't have isolating sections, they change turnouts one by one until they get the route the want. In the mean time, the odd loco may have sprung to life.

problem - what am I doing wrong??? =8^O
Well let's put it this way, your wiring isn't properly protecting from shorts. It would only need one out-of-gauge wheel set or wide wheel tread to cause shorts all round your layout on every live frog turnout.

lot cheaper than buying a DCC controller and a hundred decoders!!!
So what is 'no switches block wiring' ? Complete areas wired to one controller ? Personally, I prefer the simplicity of wiring and far more reallistic operation afforded by DCC. To my mind, all the time I spent originally wiring my layout for DC, together with all the switch gear and wire was dead money. Now the layout is wired for DCC all of the switchgear has disappeared as has 2/3 of the wiring - the cost of all the gear should have been invested in something useful like decoders in the first place and cost-wise, I would have been level!
Graham Plowman
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snipped-for-privacy@gppsoftware.com wrote:

And yet you offered advice towards a fix that have no positive effect on that situation.

It's not a problem to me as my turnouts are switched from end-point to mainline in sequence.

Anywhere you like, but I think we had better change the subject line :-)

Great - just like British and European prototypes!
In DCC,

It's also slotcar toy like.
All the

Podssibly, but it's not a huge compromise and certainly not as great as some of the DCC compromises. (in specific circumstances)

It's the reason I don't use DCC.

Yes, I know that - so does PWM DC.

Incompetency! It would be even worse with Code 75 track!

That's one of my DC system limitations - if I want to park a loco I need to be able to isolate it in a loco sized (switchable) block. Block switches are cheaper than decoders and have a longer lifespan.

Only if I'm stupid enough to link an in use controller that specific track block.
with but then

Huhh??? Of course I place locos on the track - it's specially designed to be electrified on a system compatible with my locos!
But this issue is resolvable in DC by using an

Sure, and on a short siding the electrical switching is done through the facility inherent in the Peco turnouts, the facility you claim must be eliminated!
That way you can have two locos in the same siding

Do you always leave your controllers set at full speed when you're not using them??? My circuitry is arranged so that only the route required is connected to whichever controller is linked to it. There is the point of the Peco turnout switching system, only the route selected is electrified.

As do I - with the exception of "IECC" which is an unknown abreviation to me.

Please!
The image of chimpanzees banging at typewriters to imitate Shakespeare spring to mind!

Why would I have out of gauge wheelsets??? My wheels have coned treads - I remember puzzling over a Kleinbahn brand shunter that did activate parked locos as it crossed live frogs - my standards aren't high, but they are standards! ;-)

My aim was to eliminate ALL block switches and controller selection switches from my control panel - I can't quite get there but I'm close. No, each controller is linked only to it's required route.

Sure, but realisim in operation was why I reverted to DC block control.

Certainly but instead you spend vastly more on DCC componentry - I'm poor so I have to live with my own system.

The maths didn't work for me - layout wise, and the DCC loco control didn't work for me in regard to signalling and staging yard wise.
Those are the breaks!
Regards, Greg.P.
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Greg,

that situation.
What is that supposed to mean ? Are you telling me I don't know what I am talking about ? Believe it or not, some people choose to observe and learn from the mistakes of others and implement a solution that resolves all of those issues. Yes, I made those mistakes in my early days. I don't have them on my layout now because I wire things up properly. Just because I don't have them on my layout doesn't mean I don't know what I am talking about or have never seen the problems being discussed!

mainline in sequence.
And so are mine, but don't forget, other people don't necessary have this kind of setup. And also don't forget that it is possible to get intermittent shorts while all those turnouts are changing in one go if they are not wired correctly. While a DC controller may tollerate it, the proper protection a DCC unit affords wouldn't tollerate it. That is another subject which I don't propose to go into here, but you are probably not aware of it if it does exist and I am not proposing that we investigate the possibility either.

No! If you put multiple slot cars on the track, they all go together because the track is being driven, not the individual cars.

some of the DCC compromises. (in specific circumstances)
Some of us happen to believe that the above is a huge compromise which we are not prepared to accept. Some of us also believe that the 'bowl of pasta' wiring under a DC layout is also a compromise we are not prepared to accept. I am not aware of DCC 'compromises'. What are they ?

So you don't want a more realistic level of operation ? How odd!

No! PWM DC (AFAIK) is only present on the track when the throttle is powering a loco. When the loco is stationary, there is no power on the track. In DCC the power is on the track at all times at full voltage, regardless of whether any locos are running. It's not the same thing.

Ah! Now were are getting somewhere! Yes, your DC system has a limitation and that is compromising the way you operate the layout. Point proven!

Anti-DCC scaremongering nonsense!

track block.
Point proven again! Your operating method is compromised by the traction control system.

to be electrified on a system compatible with my locos!
I think you have misunderstood. The example I provided was that you have a siding into which you are driving a train. I stated that you would have a problem if there was already a loco sitting at the end of that siding - that it would spring to life once the turnout was changed. What I then said was that without an isolating section, this is an activity you wouldn't do because it doesn't work - your operation is compromised by the control system.

I think we have a misunderstanding here. Yes, Peco turnouts can isolate sidings but that is not what an isolating section is. An isolating section is a separate length of track which is switched on/off using a switch (or relay) on a control panel. It is independent of the switching of a turnout. If a turnout livens up a siding, it does not (normally) affect the isolating section.

entirely on sidings being switched by turnouts and has no isolating sections. I cannot understand how any DC layout can provide any level of reallistic or practical operation without isolating sections. The facility you understand as me claiming to eliminate is that I believe that sidings should have isolating sections in them. This means that the switching of the turnout has no effect on the siding itself which is under the control of the isolating switch. It is really difficult to operate a layout at an exhibition without this functionality! Where I say it can all be eliminated is under DCC control because in that system, all running lines are live at all times and are not switched by turnouts, well they can be, but they don't need to be.

using them???
No, of course not, but consider shunting in sidings. A loco is on the move and you change turnouts. There is a risk that any loco already in one of the sidings can spring to life if those sidings do not have isolating sections. This means that the operation is being compromised by the control system.

whichever controller is linked to it.
This is what my computer control did in my DC days but I still had numerous isolating sections to enable some for of reallistic operation. Have a look at http://mrol.gppsoftware.com for pictures of my layout. So if you don't break switch rails on live frogs, how do you prevent unexpected feeds leaking around the layout ?

selected is electrified.
Yes, but as I keep saying, is does not resolve the issues of locos already sitting at the end of a siding - which you conceded above is a limitation of your system. It's not a limitation that I am personally prepared to accept.

to me.
IECC is 'Integrated Electronic Control Centre'. The software I use replicates the British prototype RailTrack IECC standards for computer control panels.

spring to mind!
I have certainly seen it happen on other people's layouts!

shunter that did activate parked locos as it crossed live frogs - my standards aren't high, but they are standards! ;-)
That really depends on what standards you are using and how strongly you implement them. Many Hornby locos for example, of their older products, have very wide wheel treads which can cause shorts between switch blades and stock rails. Not only that, they are out-of-gauge as well, compounding the problem. The only way to really resolve this issue is to replace the wheels, whch for a lot of people, is no mean task. Usually what happens is that they attach plastic shims to the turnouts to stop the sparking, but it is really a band-aid solution. In fact your statement of a loco activiating parked locos as it crossed live frogs is a classic clue. This is one of the many problems which can occur if switch rails are not electrically broken. The link I provided solves that problem.

switches from my control panel - I can't quite get there but I'm close.
No, each controller is linked only to it's required route.
This sounds a little bit like how my original DC setup was wired. The computer controlled relays to connect controllers to blocks where locos were running - cab control. This is OK on a running line, but it is inadequate in sidings where isolating sections are required. I really cannot see how a DC layout can get away with no isolating sections at all. The operation must be seriously compromised in some way.

But if you use DCC you can still operate a block controlled system and your wiring is very much simpler in the process. Don't get caught up in the urban myth that block control requires DC wiring!

No, only in decoders for locos. I don't power turnouts via the DCC.

didn't work for me in regard to signalling and staging yard wise.
I understand the maths but I don't understand why signalling would be a problem under DCC - it certainly isn't for me.
Regards
Graham Plowman
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No, Greg, not from you.
--
Jane
OO in the garden http://www.yddraiggoch.demon.co.uk/railway/railway.html
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wrote:

Graham has said it precisely. If the under blade contact spring plate is weakened then all current passes via the blade tip. Loco passage and / or stock will inevitably work the bladeand cause small sparks as the blade parts from the fixed rail ( being inductive can be quite noticeable.) Apart from stroking the conductor spring plate back into shape ( as one did with the old type 3000 PO relay blades) there is not much else to do. If the conductor plates are too weakened then it is a case of replacement for the point.
Peter A Montarlot
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