Rev limit hook-up?

[poopstang]

I'm trying to hook up the digital rev limiter on the HI-6S.

The directions specifically say, to activate the rev limiter functions connect the digital input(yellow/white wire) to a normally-open switch supplied with 12V?

Then your suppose to be able to adjust rev limit between 3,100-9,900 rpm on the rotary switches on the unit?

My question is about the normally-open switch? Does that mean when the car is off it's open and when it's running it's closed?