The lights draw whatever you design for. The decoder is
rated for 100 mA on each of the 4 light outputs. Thus, a sin-
gle decoder could draw as much as ½ amp (100 mA for the
decoder and sound and 4 x 100 mA lights). However, with 10
mA LEDs on all four outputs, I’d expected the nominal maxi-
mum draw to be about 0.1 amp (100 mA). Testing confirmed
this, with the nominal current consumption with the default
volume settings to be about 50 mA without any lights active.
SoundTraxx recommends one decoder for every 3 or 4 cars “for
the optimal experience”. This could have a 20-car train drawing
close to an amp: 7 SoundCars without lights drawing 100 mA
each and a couple of locos drawing 100 mA each. Realistically,
I think a through freight will have each car drawing about 50
mA. However, it is something to think about when considering
layout design and fleet operations.
