DCC Bus wiring

[TonyG]

Hi All

Need some help with which bus wire to use. Layout is small branch line end to end 17' long. My system is digitrax super chief 8amp and their rather large power supply. I know its overkill but it is all I could get at the time. nobody had the 5amp in stock. My question is which wire to use for main bus 32/02 and 16/02 for the droppers. I will only be using 2 locos at anyone time no sound at the moment but at some point I will. Can someone verify this system is ok or do I need to upgrade the wire. Your assistance will be most appreciated. This layout is O gauge and all locos have canon motors

 

Tony

Edited December 7, 2017 by TonyG

[Nigelcliffe]

You need wire and joints which are adequate to always shut down the system in the event of a short, anywhere.   With more current, the wiring requirements get more onerous. 

 

I'd suggest that you use the wire proposed, but also add a power district breaker to the system to limit the current going out along the bus (and to the layout) to something more sensible - perhaps nearer 3A or 4A.   Then your wiring is less critical.  

 

 

- Nigel

[amdaley]

Hi All

Need some help with which bus wire to use. Layout is small branch line end to end 17' long. My system is digitrax super chief 8amp and their rather large power supply. I know its overkill but it is all I could get at the time. nobody had the 5amp in stock. My question is which wire to use for main bus 32/02 and 16/02 for the droppers. I will only be using 2 locos at anyone time no sound at the moment but at some point I will. Can someone verify this system is ok or do I need to upgrade the wire. Your assistance will be most appreciated. This layout is O gauge and all locos have canon motors

 

Tony

 

Hi Tony.

 

I would suggest that you upgrade the main bus wire to 50/0.25 which is 14 awg.

32/0.2 is only 18 awg which is really to small for O gauge.

Use the 32/0.2 for droppers.

Use plenty of droppers as you can never have to many.

Also make sure that any wiring connections you make are capable of taking the full amps that your system is putting out.

 

I would also use a circuit breaker so that in the event of a short you don't get the full 8 amps going through the short.

If you later decide to put more locos on the layout or upgrade to sound then you can adjust the circuit breaker to allow larger amps through to the track.

 

In the event of a short your system must shut down immediately.

If your wiring is inadequate then your system won't see the short & that can lead to serious trouble.

 

Tony.

[RAF96]

My main bus pair are ex 2.5mm2 mains cable. Droppers are 1mm ditto.

 

This will handle any amount of model railway current with spare without voltage drop over considerable length.

 

Rob

[hobbyhorse]

I've used 32/0.2 for the bus and 22/0.2 for the droppers, also using the Digitrax system.

Had no problems with it.

Edited December 6, 2017 by hobbyhorse