Help with DC wiring

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alex3410
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Help with DC wiring

Postby alex3410 » Sat Sep 22, 2018 2:43 pm

Hey guys,

i wanted to run this one past you all as my mindset is very DCC :lol:

Anyway a friend of the family has set up this layout for their son, they are having issues with locos not making it all of the way around the loops and suspect power issues - they have asked where they should be placing the power wires?

Any thoughts would be appreciated

it really does make me appreciate DCC :lol:
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Bufferstop
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Re: Help with DC wiring

Postby Bufferstop » Sat Sep 22, 2018 5:54 pm

If they are insulfrog points almost anywhere will do. If they are electro frog, at the simplest, just the same as DCC. Fit IRJs on the V rails unless you want the track beyond the point to be point switched. So a circle of track, with a passing loop, would be fed from somewhere on the circle and each of the rails at the centre of the passing loop would be powered from one point or the other. If you have a single siding, just a single IRJ in the V rail on the main to prevent a short circuit when the point is set to the siding.
From your photo they all appear to be settrack, so the only IRJs needed are on the crossovers assuming there are two controllers. I'd feed each loop with two feeds, one at the left and one at the right on each loop.
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Mountain
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Re: Help with DC wiring

Postby Mountain » Sat Sep 22, 2018 7:39 pm

I was looking at the picture and admiring the design but unfortunately I have seen a small issue which is related to the track and not the electrical side of things. The double track at the top left side of the layout. It looks like the two rails are too close to each other. This can be rectified by taking out the curved point and using normal curves, then adding a standard left hand point where the first straight section is, and then using the curved point in the area of the sidings.
I dont want to stand in the way of progress, but addressing this issue now will prevent issues later if it makes sense. Other then that the plan is a good one. I like the sidings that come off the diamond crossing. They look very good, and so do the platforms etc.
Enjoying 7mm narrow gauge.

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Emettman
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Re: Help with DC wiring

Postby Emettman » Sat Sep 22, 2018 9:38 pm

Assuming two controllers, the simplest wiring is simply 1 two-wire feed to each oval. At the left-hand end just above the curved point would be convenient.
No insulating joiners are necessary.

The other reasons for failing to complete and oval would be loose fishplates at rail joints or point blades failing to make good electrical contact.
The latter can be permanently solved by wiring the points to non-isolating mode, but that will need more wire, switches and isolating rail joiners to restore the isolating function.

Chris.
"It's his madness that keeps him sane."

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Mountain
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Re: Help with DC wiring

Postby Mountain » Sun Sep 23, 2018 12:14 am

The only place recommended to place IRJ's are at the crossover between the two ovals of track. The reason for this is where one may have a double controller which is not suitable for common return wiring, and though this may not be common return it may have a similar effect.
Dont get me wrong, in the past I never used IRJ's in between the two points at such a crossover and never had an issue but my controllers all were single controllers with their own transformers, so I wouldn't get a problem in this way. (This was before I learnt how to wire a layout the cab control method, and later rewiring of my last layout due to a major track plan change led me to also adopt common return wiring to the cab control wiring method which enabled me to free up a pole on each section switch, which I used for panel bulb display purposes).
Enjoying 7mm narrow gauge.

Mike Parkes
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Re: Help with DC wiring

Postby Mike Parkes » Sun Sep 23, 2018 10:20 am

Ideally the feed in the inner circuit should be between the point to the goods yard and the station area and the feed on the outer circuit between the crossovers and the station point (ie both to the left side of the layout as photoed). The crossover and goods yard point will if set wrong cause a dead section on the inner loop, and the crossovers and station points the same on the outer loop which is probably a good safety feature. Never had much luck with the setback diamond crossing and short wheelbase locos so it might be better that the two sidings accessed by the diamond are accessed by a LH point instead from the inner circuit and the crossover relocated to the left of that point. Also the curve to the right side looks like the tracks may be too close together.

Suzie
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Re: Help with DC wiring

Postby Suzie » Mon Sep 24, 2018 1:35 am

Assuming that you have two controllers then feed to the left as people above have said. Because there is a crossover controllers suitable for common return wiring will be required.

There is a need for an insulated joiner or isolating track in the outer rail of the inner track above the feed (perhaps at the left of the top station) so that the crossover can be used without the two controllers being connected at once. The crossover will be powered by the outer controller when in use while the inner controller will continue to operate the inner 3-road goods yard if required.

The tracks being too close together is caused by using 3rd radius on the inner (the outer part of the curved point) and second radius on the outer (the curved part of the straight points). The curved point is really not working well where it has been positioned, especially if the inner circuit is primarily 1st radius. It would work much better if placed at the transition between curved and straight at the bottom where it would create a transition curve.

Curved points work really well to create a 3rd radius loop outside of second radius and they would do very well on the outer station loop at the top to remove the sudden straight bit of the straight points that are currently in use.

Suzie x

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alex3410
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Re: Help with DC wiring

Postby alex3410 » Thu Sep 27, 2018 9:07 am

Thank you guys, i really appreciate you taking the time to help out.

i will pass on the comments :)


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