New to n guage

[ntpntpntp]

Disabling DC support in a decoder is often to avoid "runaways" where interruptions in the DCC signal detected by the decoder can cause it erroneously to assume it's on DC and hence ignore commands.  It's usually a requirement to disable DC support if you use "Brake on DC" for automated signal stops, or if you fit any sort of power buffer. 

Other than that, disabling DC support has no effect on running properties, though it does mean the decoder firmware has one less thing to monitor for.

[Sprintex]

I was just typing a similar response and you beat me to it


Paul

[njee20]

I find all my Digitrax equipped locos run away when there's a short if I have DC enabled, so I always disable it.