Dcc bus power requirements

[Smithy589]

Good day,

as the TT:120 is a new scale and along with it also electrical power requirements do we have any figures in relation to what these are. E.g. how much current each loco draws when running?

i am looking to design a layout that has approx 80 m of track and was wondering what the power requirements would be for say each loco.  There is also the issue of coach lighting to consider with the flying Scotsman setup.   
 

I have seen the DCC Concepts alpha box which works as a Dcc booster rated at 5 Amps.  Am I right in thinking that this will provide the layout with the required current when it needs to draw it to operate the various “bits and pieces”

Any help/ thoughts / guidance appreciated.

thanks in advance

regards 

Colin

[ntpntpntp]

The length of track is kind of irrelevant.    How many locos will be running at the same time, how many others + lit coaches will be sitting active on the layout?  Sound locos add to the power draw.

The motors in the locos are reasonably efficient from what I can tell, though I only have a couple in TT (hundreds in N).  When servicing locos I expect to observe around 100 - 150mA when running light, some modern coreless motors being even less. 

I like to allow plenty of headroom and reckon on something like 500mA per running train in the smaller scales (N, TT, 00) which is probably double the actual draw in a lot of cases.    I'm sure a 5 amp booster is usually sufficient for most people's home layouts.  If you really will need more power then separate the layout into power districts each with its own booster. 

Try and keep other power drains such as lighting accessories on a completely separate AC or DC bus, there's no need to waste DCC track power on them. 

[Charlie 66]

6 hours ago, Smithy589 said:

Good day,

as the TT:120 is a new scale and along with it also electrical power requirements do we have any figures in relation to what these are. E.g. how much current each loco draws when running?

i am looking to design a layout that has approx 80 m of track and was wondering what the power requirements would be for say each loco.  There is also the issue of coach lighting to consider with the flying Scotsman setup.   
 

I have seen the DCC Concepts alpha box which works as a Dcc booster rated at 5 Amps.  Am I right in thinking that this will provide the layout with the required current when it needs to draw it to operate the various “bits and pieces”

Any help/ thoughts / guidance appreciated.

thanks in advance

regards 

Colin

Hi Smithy,

I'm a newbie and I know there are plenty of very knowledgeable modellers out there who can get technical for you.  For what it's worth, I've got about 55m of TT gauge track and am using an Elite running 5 loco's plus 34 point motors and associated LED signals off micro switches with no issues for me.  I am using a separate bus circuit for all accessories (Street lights etc).  Going up to 80m I'd definitely create at least 3 power zones - which also helps against shorts.

[96RAF]

You can split the layout into as many power districts as you like but if most of your locos congregate in one district you have defeated the system. The prime idea of power districts is load spreading, so you need to think more along the lines of which layout working areas need to be separate load districts by dint of track traffic density. Secondary is being able to have isolated sections to aid fault finding, but realistically once you get the layout wired up and commissioned into running, there should never be any need for such problem solving.

[Fishmanoz]

My rule of thumb - you don’t need a booster until your layout fills both car spots in your double garage.  Although that is an OO comment.

Using a Hornby controller with their 4 Amp supply will likely run 10-12 trains at the same time and meet your needs without a booster.

However, you can future-proof it by wiring it up in 2 districts with separate buses then, in the first instance, wire both districts together to the one controller and see how you go.  If you find later you are running out of power, separate the buses and power the second with a booster.