Wiring the Tracks

Most books seem to suggest using the inner rail of complete circuits as the 'common' connection and that this will usually be the 'negative'. On an end-to-end layout it probably doesn't matter much, provided you are consistant.

I belive model locos are wired to a standard so that all will move consistently one way if placed on a track facing one way and with the same polarity of voltage applied to the track. But I cannot remember (or find out!) what that convention is.

Regards,
John Webb

Hiya,

I always put a complete loop in under the board first ten ake spurs of it for my track connections. Make sure the loop is of thicker wire than the spurs tho!!! It alows the power to be the same all across the layout then. I also put loops in for all my lighting circuits ( i normally use a 6 volt and a 12v lighting circuit so my LED circuit is totally seperate to the Grain of wheat circuit. as for which side is plus or minus i always just mark one side as + or - and stick with that. Never seem to have had any problems so far..................................

Nikki

QUOTE I know this seems like a daft question but is there a side of the track that is always minus and the other plus!!

well..yes and no.

'yes' in that one must ensure both sides are insulated from each other, otherwise one builds a very large toaster.

but 'no' in that, given the above it really doesn't matter.

If you cannot get 'on' with the direction the controller moves the loco when set 'forwards'....ie the loco doesn't go in the direction you are happy with, given the 'set' of the controller....simply reverse its output wires.

regarding the manufacturers, and a convention for the wiring of a loco chassis, what none of them want is for you to try and double-head with differing makers products...to end up with a tug-of-war!
It's bad enough simply choosing locos with a matched performance......or maybe an A4 Mallard WILL be happy double headed with a Jinty..?

Just to say - i didnt mention the fact that i only make dcc layouts, so if you wanted to do it analouge then thats all sections................... Then you should run the negative on a loop but the positive will have to go to switches for sections etc ................ There is a great book on model railway electronics - i cant remeber who wrote it but its got a blue cover.... will try and find out for you...........................

Nikki

Thankyou all for taking the time to answer I think now that I have the idea!! Just keep everything the same on each track side!!!

Many thanks again

Kind regards

Paul

For which rail is positive:-

From the NMRA standards ( to which I think all manufacturers follow)
http://www.nmra.org/standards/sandrp/pdf/s-9.pdf

Direction control by polarity reversing shall be provided. Positive potential applied to the right hand rail shall
produce forward motion. (3)
(3) The term "right hand rail" as used herein means the rail to the right of the observer standing between the rails
with their back to the front of the locomotive.

There is a great book on model railway electronics - i cant remeber who wrote it but its got a blue cover.... will try and find out for you...........................
Is it the complete book of model railway electronics by Roger Amos?

Yes,

I think that might be the right book!!! Im sure that rings bells somewhere !!!!!!

Nikki

Hi - I am new to this also but I agree with previous posts. As long as you don't create a short circuit all will be well. It doesn't reallly matter whether positive (or -ve) is 'left' or 'right'; if the trains don't go the direction you want them to go in simply switch the wires round at the controller. Remember to use insulating connectors between circuits and make sure that the polarities of different circuits are the same.