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Dcc layout wiring help required for bus and dropper system

8735 Views 37 Replies 8 Participants Last post by  harkins77
Hi guys I was wondering if someone can give me some help using the bus and droppers wiring system for my new plan.

I'm struggling where to isolate and put power feeds for the layout

Below is the plan I have and I'm wondering if someone could help me please.

http://www.modelrailforum.com/forums/uploa...71_60_32319.jpg

Ok so another thing I'm not exactly sure of if I run a bus wire do the 2 ends of each wire i.e. + and - do they connect together to form a loop before going to my powercab system? Or does the end of the + and - wire end just before it meets up with the start of the wiring ?

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No loop required, position the controller central (ish) and then run the bus out from there.

Richard Johnson has some perfect tag strips for dropper to bus connection complete with a nice wire stripper for in line stripping (not just ends) that will make this a breeze. I have them and they are great, tag strips and strippers (wire strippers that is
)

The other point is , are you going to use some form of power management to divide the layout into blocks such that a short on one part of the layout doesn't shut down the rest? If so you end up with a bus for each of these power districts. Looking at your layout you may want a couple of power districts perhap each of the three loops perhaps?

What DCC system are you using?

QUOTE (harkins77 @ 16 Jul 2008, 06:30) <{POST_SNAPBACK}>Hi guys I was wondering if someone can give me some help using the bus and droppers wiring system for my new plan.

I'm struggling where to isolate and put power feeds for the layout

Below is the plan I have and I'm wondering if someone could help me please.

http://www.modelrailforum.com/forums/uploa...71_60_32319.jpg

Ok so another thing I'm not exactly sure of if I run a bus wire do the 2 ends of each wire i.e. + and - do they connect together to form a loop before going to my powercab system? Or does the end of the + and - wire end just before it meets up with the start of the wiring ?
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QUOTE (harkins77 @ 16 Jul 2008, 06:30) <{POST_SNAPBACK}>Hi guys I was wondering if someone can give me some help using the bus and droppers wiring system for my new plan.

I'm struggling where to isolate and put power feeds for the layout

Below is the plan I have and I'm wondering if someone could help me please.

http://www.modelrailforum.com/forums/uploa...71_60_32319.jpg

Ok so another thing I'm not exactly sure of if I run a bus wire do the 2 ends of each wire i.e. + and - do they connect together to form a loop before going to my powercab system? Or does the end of the + and - wire end just before it meets up with the start of the wiring ?

***Hi

Basically the bus should have the control system roughly central and form a T shape. It should not form a loop.

Wire for bus 32/.2 and droppers appx half that.

Isolation: One siding for programming track, then anywhere you might want to turn off for operational reasons. Apart from that, only absolutely needed where / if needed by the type of pointwork you have chosen.

Its not strictly necessary but you should perhaps plan to make the layout in say 4 isolatable electrical sections. They can be simply geographical ie north/east/west/south or trak related ie station, yard, left half of loops, right half of loops. That will allow you to turn them off in the case of a problem so you can at least localise the area of problem.

regards

Richard
DCCconcepts
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Thanks for the replies guys. I'm still a little in the dark what you mean by a t shape though Richard. I just can't picture what you are meaning in my head. A diagram would be helpfull in what you mean though.

The system I am using lancashire is the nce powercab system to power the layout.

Looking at a previous diagram that Brian did for me for my last attempt at a dcc layout shows me where to place the powerfeeds and also where to place the isolating sections. I have included below the drawing that brian did for my last layout which was easy enough to understand for a sticko like me.

Sorry but I forgot to mention as well that it is kato track for the majority of the new layout with some peco flexitrack for the sidings lines.

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Hi All
From what I understand of The "T" shape
pick a central point for the wiring from the power cab and run your Bus wires Left and right from there
to your droppers from the track
Hope this helps
Regards Zmil
QUOTE (zmil @ 16 Jul 2008, 18:59) <{POST_SNAPBACK}>Hi All
From what I understand of The "T" shape
pick a central point for the wiring from the power cab and run your Bus wires Left and right from there
to your droppers from the track
Hope this helps
Regards Zmil

***Yep.... spot on

Richard
DCCconcepts
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So you mean something like this?

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Yes, thats exactly right

Richard
So with regards to the isolating joiners where would I put each of them then to stop any chance of an overload or is there no need for them?
QUOTE (harkins77 @ 17 Jul 2008, 03:23) <{POST_SNAPBACK}>So with regards to the isolating joiners where would I put each of them then to stop any chance of an overload or is there no need for them?

*** If you mean an overload as in too much current drawn by running loco's then its not an issue. If you mean to isolate the various parts of the layout so you can install local short circuit protection or turn places off at will then that choice is yours.

See post # 3 of this thread.

I'm not sure what else you want in the way of info.

Most of it is simple logic and personal choice of which parts you want to separate electically for your own operational wants and needs. The basics of this are only changed by the nature of the points you choose to use..... and their need for any isolation is in their instructions.

Please ask if there's something I've not covered here, but DO have a go at this yourself first as its important to go through the procedure of thinking it through yourself as thats the only way to learn.

From memory you now use an NCE powerCab???? if so there is a good clear example of breaking a layout into power districts etc in the manual.

Richard
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yeah that's right richard and also with me using Kato unitrack the points have directional power according to the website that sells them at least.

"All points are self-isolating (Just like Peco), #4 points (#20-220/221) also have full power routing capability." And these are the points that I have.
Ok so before I take the plunge and place my dropper wires to the tracks so then all I need to do is get my bus wire to connect them to. I have done a diagram for where I think I need to place the isolated joiners and also where to wire the dropper wires to.

Please could someone take a look and see if I have got everything covered and tell me if I am going to run into any problems.

Just to cover the basics again.

I'm using the nce powerpro system. The track is Kato Unitrack and the points are self isolating with auto power routing on them.

I have also included the key to the left of the layout to explain what everything stands for as well.

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QUOTE (harkins77 @ 21 Jul 2008, 07:26) <{POST_SNAPBACK}>Ok so before I take the plunge and place my dropper wires to the tracks so then all I need to do is get my bus wire to connect them to. I have done a diagram for where I think I need to place the isolated joiners and also where to wire the dropper wires to.

Please could someone take a look and see if I have got everything covered and tell me if I am going to run into any problems.

Just to cover the basics again.

I'm using the nce powerpro system. The track is Kato Unitrack and the points are self isolating with auto power routing on them.

I have also included the key to the left of the layout to explain what everything stands for as well.

***HI

It looks fine as is

Richard
DCCconcepts
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ok thanks for that Richard. I'm going to make a start on installing the droppers today. I should if everything goes ok have all the droppers in place by the time it comes to going to work tonight.
Ok so the droppers and isolating sections are now in place.

Started at 11.30am this morning and just finished at 16.35pm.

So just have to wait to get the main bus wires hopefully on Friday and then hopefully I should be up and running assuming that I have done everything right.

I have checked checked and checked 2 more times to make sure I have covered everything so there isn't anything I have missed. (trust me to say that I probably have overlooked something now I have said I have checked everything something is bound to go slightly wrong but that's all the fun of this hobby.)
right I've had my first testing of at least 1 line on the layout and apart from a little light cleaning of the track it went very well. I only connected up one of the droppers to the nce system just to test the middle line and am really chuffed with myself as it actually works...lol.

Thanks to all who have helped me so far and I look forward to fitting the bus wires and then having the whole layout to run around on.
QUOTE (harkins77 @ 23 Jul 2008, 01:37) <{POST_SNAPBACK}>right I've had my first testing of at least 1 line on the layout and apart from a little light cleaning of the track it went very well. I only connected up one of the droppers to the nce system just to test the middle line and am really chuffed with myself as it actually works...lol.

Thanks to all who have helped me so far and I look forward to fitting the bus wires and then having the whole layout to run around on.

***We all knew you'd get it right - only you were doubtful :) :). Be confident and go for it!

Richard
Just out of curiosity about the bus wire Richard I have been told that if I don't get the right gauge wire for the main bus wire I could suffer some kind of electrical problem. Now I'm using 7/0.2 wire for the droppers from the tracks and I have taken on board what you have said about what wire I need for the 32/0.2 wire for the bus wire should I have any problems using those 2 kinds of wire together?
QUOTE (harkins77 @ 23 Jul 2008, 23:02) <{POST_SNAPBACK}>Just out of curiosity about the bus wire Richard I have been told that if I don't get the right gauge wire for the main bus wire I could suffer some kind of electrical problem. Now I'm using 7/0.2 wire for the droppers from the tracks and I have taken on board what you have said about what wire I need for the 32/0.2 wire for the bus wire should I have any problems using those 2 kinds of wire together?

***Hi

With a smallish layout you'll be fine. the 32/02 is good for the bus and the 7/02 a wee bit finer than I'd recommend for droppers but keep them less than 300mm length max for each wire and just do it - it'll work fine.

the issue is well misunderstood, especially by those who run off to find charts of wire resistance :) :)

On larger layouts where when the bus is long loading is high voltage will always drop - not just because of normal cable resistance but also because of the inductance caused when two wires under load are close together and carrying a waveform, they create inductance which will add to the cable resistance significantly.

for your layout, it won't be an issue, so just be confident and solder away!!

Richard
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ok thanks for that Richard.

For connecting the droppers to the main bus would you recommend wrapping the dropper wires round the main bus wire and then soldering them together or just wrap the droppers onto the bus wire and then wrap it in tape just in case there is a problem later
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