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QUOTE (Brian @ 13 Feb 2008, 22:14) <{POST_SNAPBACK}>Hi
Radial means not returning back to the place where the supply was inputted (Which is what a ring does) or in other words it starts at the supply and ends somewhere else. You an also have a radial that's 'T' feed. i.e. from supply to roughly the centre of the two main bus wires which then radiate out around the layout in roughly equal lenghts.

I have used a 2.5mm solid copper insulated wire (ex mains power point cable) as a bus on my layout (in radial format) with 16/02mm droppers coming off the bus and then connecting onto solid wire droppers from the rails above. These are made from some 1.0mm bare copper earth wire. But you can solder the 16/02mm wire directly onto the rails if wished.

Hi Guys,

I was also going to follow domestic electrical 'best practice' and install my DCC Bus as a ring main but thanks to Brian, who incidentally has many years of model railway experience and is also an ex BR signalling engineer kindly explained to me as follows why it should be wired as a Radial.

If you have a DCC ring main and you send a signal/instruction to a loco which is on a section of track which is connected say 1/3rd of the way round the DCC ring main the signal will actually travel in both directions around the ring main and will arrive firstly along the shortest route between the controller and the loco.

However, milliseconds later, the signal will arrive again along the longer route between controller and loco.

The loco will therefore receive the same signal twice which can, apparently, cause its little brain to become confused and may result in unpredictable consequences. Hence you should use a DCC Radial Bus to ensure that the signal/instruction only arrives once at the loco.

Brian, I hope I have done justice to the explanation you gave me.


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