Common ground for sensors?

[Jared Russell]

Hi,

In wiring up all the sensors we're using this year, I was wondering if we could save some cable and use a common ground (and for that matter, common +5V line too - provided that we can prove that the maximum total current drain on the line is less than what it is rated for).

Anybody know if FIRST allows this (my guess is yes, just wanted to be sure).

[Al Skierkiewicz]

Jared,
You can use a common power point (a 20 amp breaker) as long as you don't have a ton of sensors on it. A big ball of wire attached to one lonely breaker is going to attract the attention of the inspectors. Grounds are the same but I recommend you run parallel wires from the sensors back to some common point. A custom circuit board is great for this. Even if there is nothing else on it, it can provide a convenient (and reliable) spot to terminate the power and grounds and it can be insulated inside a nice plastic box.