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Hi

I am at last on with my dcc layout and before purchasing or doing any wiring would like to know what size of wire to use for the power bus and droppers, advice has been anything from household mains wire for the power bus to handle up to 20amps down to 0.02mm sold in most railway shops for general wiring, the same for dropper wires.

I would rather be covered and dont want to turn it on and all the wires turn a nice shade of red ....... lol

Also i presume copper core is a better conductor for a signal in dcc, should it be multistrand or single core ?

Suggestions of a supplier would be welcomed, the cost is not an issue as it i want it to be right first time.

The layout covers two boards in an L shape 6ft X 2 6" one way onto 6ft x 2ft, with two levels would an NCE procab be ok to supply all needs for the track without a booster, as all accesories /points are covered with a Gaugemaster D or DS controller.

upnick.
 

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Hi Upnick,

I bought a DCC Bus System from Express Models and the wire sizes are as follows :-

1. Main Bus Wire - 16 x 0.2mm stranded copper.
2. Track connection/dropper wire - 7 x 0.2mm stranded copper.

These wire sizes are the same as those recommended by Brian Lambert on his web site.

Trust this helps.

Expat.
 

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Just another modeller
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Hi

Trevors advice is fine for a layout of the size you are building.... On the other hand if it was much larger I'd rate Brians recommendations as too light for best performance under all conditions.

Conversely those who you mentioned in passing recommended that light weight of wire you mentioned just do not know what they are talking about for either a DC or DCC layout - it is simply too fine and under any load at all you will have voltage drop if used for any length at all...!

Just to explain, the wire size isn't to handle high current, it is to guarantee no voltage drop under load.

My usual recommendation for a smaller layout is the same as 10 amp mains wire in copper diameter, same copper diameter as 15 amp mains wire for a medium layout and same copper as 20 amp for a larger one.

Generally stranded wire is easier for most to work with.

Practicality rules when it comes to having to solder wire to rail tidily - So smakker sizes are helpful - anyway, droppers can actually be quite small, providing they are short - if kept below 300mm then wire thats sold as "medium hookup wire" is about right.

Kind regards

Richard
DCCconcepts
 

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Just to clear up a point..... (Sorry Expat) My web site recommends 1.5mm or better still 2.5mm wire for the main DCC bus on a medium to large layout.
Larger layouts would need a bigger gauge of bus wire, up to 4.0mm. However, then it's really time to start fitting power districts and boosters!

I recommend 16/02mm wire for connection between the main DCC bus wires and the track or to the dropper from the track.

7/02mm is recommended for most other applications such as lighting, point operation and indication circuits returning to any control panel etc.


QUOTE From the bus, there will be many connections between it and the running rails to ensure reliable data transfer into the rails and hence onto the loco's wheels and the decoders. I advocate a DCC bus being made of at least 1.5mm2 or better still 2.5mm2 wire as used in domestic wiring cables. I don't like flex for the bus, though this can be used if preferred, and may be especially useful on portable layouts!
 

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QUOTE (Expat @ 10 Mar 2008, 12:03) <{POST_SNAPBACK}>Hi Upnick,

I bought a DCC Bus System from Express Models and the wire sizes are as follows :-

1. Main Bus Wire - 16 x 0.2mm stranded copper.
2. Track connection/dropper wire - 7 x 0.2mm stranded copper.

These wire sizes are the same as those recommended by Brian Lambert on his web site.

Trust this helps.

Expat.

I contacted Express Models a few months ago and enquired what size their DCC bus wire was. Their reply was its 30/025mm
Trevor, you may wish to recheck what you have been supplied with?

Email as recieved from Express Models..
QUOTE The power bus cable is 30 / 0.25mm. 21amp.
Outside diameter 3.3mm. Conductor cross section area 1.5mm squ. mm.

Kind regards

Rob
EXPRESS MODELS
 

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Hi Guys,

Sorry. My mistake. Getting mixed up with the DC Bus for Lighting.

Have just got home and, having checked the Express Models kit can confirm that the Main DCC Bus Wire is, as Express Models state, 30 x 0.25mm and the droppers are 7 x 0.2mm.

Just out of interest, what size should the wire be for the 16v AC Power Bus for point motors ??? I was planning on using the same as for the lighting i.e. 16 x 0.2mm supply bus with the individual returns to the mimic panel in 7 x 0.2mm.

Expat.
 

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Brian,

Personal apologies to you.

I was having lunch in the office and having a look at MRF. I should have checked your web site before misquoting you instead of relying on my obviously defective memory.

Expat.
 

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Hi Expat
Appoligies not needed at all.
I just wanted to ensure both yourself and anyonelse reading the topic understood the actual item and to confirm the Bus wire gauge you were planning on using etc.
I hope BB know of this lunchtime surfing?


16/02mm is rated at 3.0amps and would be ideal for a 16v ac bus as I doubt if your 16v ac transformer is rated that high? It can also be used singly or doubled up to make a common return wire for everything that's non DCC operated. (Doubling up the 16/02mm if its needed, saves buying in lenghts of 24/02mm or 32/02mm specially)

7/02mm is a good choice for the indication circuits coming back to the panel.

All the best and take care


Brian
 
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