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DC wiring but future-proofed for DCC


Norm81

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I'm in the process of building a shunting plank, 5' x 18" which only has a peco double slip and three points, all insulfrog.

 

I want to wire it for DC but be able to change to DCC at a later date, so checking my understandings are correct:

  • Dropper from every piece of track.
  • Snip the wires on the underside of the peco points which link across from the switchblades to the sections after the frog?
  • Feed the sections after the frogs using the switches on the point motors (as if they were electrofrog) and isolate them from the attached track sections.
  • Make the whole layout live.
  • Put isolating sections (i.e. a break in what would be the DCC bus) anywhere I want a loco to stand.

The reason I'm sticking with insulfrog is I've already got them from years ago. I plan on using tortoise point motors.

 

The aim here is to have a working DC layout that can be very quickly converted to DCC - at least without pulling track up!

 

I'm not sure this is in the right place and I've had a look around but am still struggling for answers so apologies if this is a repeat question or in the wrong forum!

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The whole layout doesn't need to be live. How I would do it is I would rig choco blocks with your droppers on one side, and the other side connected to the control panel for now. Then, if you decide to go to DCC, you can either 1. Turn on all the section switches & leave them on, or 2. rewire the droppers to a bus wire. You may find that you need to redo some of it to allow the DCC unit to overload properly.

 

It's good practice to feed the rails on any turnout, rather than relying on the tabs. I'd wire the turnouts like they were electrofrog, with IRJ's at the V's & wiring to match. The more work I do on them, the more sound that system seems to be to ensure best contact. (I'm not saying that the tabs alone won't work, but that it might not be the best idea...)

 

James

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My shunting plank is a classic Inglenook and has live frog points. The wiring is so simple as it is only run on a one loco in steam at any time and it feeds the headshunt.

 

If you think where do I need power in the DC world you can't go too far wrong for future DCC. You only need extra feeds if you intend to park a loco (with say lights and sound on) in a siding with the point against it.

 

My main layout is still really using the DC wiring and I ought to add extra feeds for when points are against a loco. You can make the wiring as simple or complex as you want.

 

One suggestion for DC or DCC is always feed the track with the same wires. I use 4 pair (8 wires) as this gives me white (with a coloured mark) and same coloured wire as one pair. All white wires go to rear rail colours front.

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Thanks for the replies, i'll certainly be treating the points as if they were electrofrog.

 

It's an inglenook with an added station, so I effectively only really need two feeds, one for the road in from the fiddle yard and one for the inglenook headshunt. Two locos in steam is the max at any one time. Will have to get myself a layout topic up once the woodworking is done.

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The easisest way is to wire it for cab control with 2 wires (+ve and -ve ) going to each section that you want to isolate. Then all you would need to do is to common those feeds in your control panel to take the DCC feed. Otherwise I think it sounds fine.

 

Jamie

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When using a dcc controller, with a larger current capability than the original, typically <1A, analogue controller, it is important to check that you still have the 'anticipated' protection in place from a short-circuit, or near-short circuit!

Therefore, if replacing it with a low-current 'starter' DCC controller, with only 1A ouptut: no probable difference, but if it is capable of 3-5Amps [or more!] , then the following should be checked....

1/ Is your existing wiring capable of supplying the maximum current, continuously, and without introducing a noticeable voltage drop, at any part of the layout: aim for about 1V drop between no load and full load, in the extreme case.

2/ ABOVE the Maxiumum current, there is the risk of a short-circuit occuring ANYWHERE on the layout: check that this will trip the safety protection of the chosen controller - the so-called CoinTest. Again, the more powerful the DCC Central Unit/Booster, the more current can run normally, and will do during a 'short': so wiring resistance MUST be lower, to match.

This is one reason why 'specific' wiring answers cannot be given as to suitable cable - because it depends on the Controller Output CAPABILITY and the size of the layout / length of busses involved.

YOUR WORST CASE scenario is a continuous fault current around the maximum from the controller - ie still acceptable and not causing a protective shutdown: eg 3A in a faulty frog-switch.

(As an example I experienced some years ago: one reason why I monitor current and voltage from the controller [some display this by LEDs or LCD panel].

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Thanks for the replies, i'll certainly be treating the points as if they were electrofrog.

 

I cannot see any justification for this false economy. Insulfrog points really have no place on any layout IMO. This is even worse on a shunting plank where you are likely to be using 0-4-0 loco or have a desire for slow running. Insulfrog points have no advantages worthy of their purchase. Replace them and sell them on to some other unsuspecting problem seeker.

 

Once you have live points and wire them correctly then there is very little to do but introduce section switches where you wish to park a loco in DC.

 

There is absolutely no difference in wiring a DCC or DC layout - especially for a short plank - other than those section switches. On a correctly wired DC layout all you should need to do is throw the section switches and swap in the controller and you have a perfectly functioning DCC layout.

 

The myth that there is some special requirements has been brought about by poor and inadequately wired DC.

 

You have gone to the trouble of purchasing a reliable 1st class turnout motor don't waste them on insulfrog points.

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I cannot see any justification for this false economy. Insulfrog points really have no place on any layout IMO. This is even worse on a shunting plank where you are likely to be using 0-4-0 loco or have a desire for slow running. Insulfrog points have no advantages worthy of their purchase. Replace them and sell them on to some other unsuspecting problem seeker.

 

Once you have live points and wire them correctly then there is very little to do but introduce section switches where you wish to park a loco in DC.

 

There is absolutely no difference in wiring a DCC or DC layout - especially for a short plank - other than those section switches. On a correctly wired DC layout all you should need to do is throw the section switches and swap in the controller and you have a perfectly functioning DCC layout.

 

The myth that there is some special requirements has been brought about by poor and inadequately wired DC.

 

You have gone to the trouble of purchasing a reliable 1st class turnout motor don't waste them on insulfrog points.

I can't argue with your logic, as I was tending towards the same solution but trying to figure how to lose the least money selling the insulfrog ones. I might aswell go code 75 and do the same with the lengths of peco flexi I've got too.

 

I thought the difference between DC and DCC was that DCC needed a bus with droppers from each track section all wired up, wheras DC needs a feed to the toe end of every point and isolating sections. Maybe that's for bigger layouts though not a relatively compact one. Wonder if there's a "DCC for dummies" book!

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I thought the difference between DC and DCC was that DCC needed a bus with droppers from each track section all wired up, wheras DC needs a feed to the toe end of every point and isolating sections. Maybe that's for bigger layouts though not a relatively compact one. Wonder if there's a "DCC for dummies" book!

 

Not really. That is the Peco way of wiring a DC layout. I have always wired DC with a bus feeding every track rather than taking the view of least wire and most risk. It is a bit like some people have always trusted the switch rail of Peco/Hornby points to make perfect electrical contact/continuity forever. I don't. I have always used a bus with droppers from the rails at frequent intervals, with the only nod to a difference being the introduction of switches. On large layouts with multiple boards and even multiple control panels things can get much more complex for both DC and DCC.

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