Arduino build with custom PCBs

[Copperhead Motorsports Park]

Hopefully no hard feelings. I wish you well with the track and your plans for it. I just tend to go a bit more conservative with my wiring. That's just my 40 + years of engineering and slot racing lesson learned coming through.

Nope, none at all. I did consider some of your advice. I actually shorted out the rails on a lane. Fuse blew. Relay is fine. I don't know how well it would fare with multiple shorts, but not having had one (other than that deliberate test) in the years of racing, I figure I should be okay.