Don't put it on your steering wheel! It is too easy to have an accident with it. As to a safety circuit, there are controls in a delay box for that. I was paranoid about switch bounce in mine so I programmed a big delay to avoid the transbrake re-energizing for several seconds. The problem with that was that I would need to re-energize it now and then at the starting line and I would be stuck. I took the delay out, and no problems. Mine is mounted on a pedestal built off of my shift platform. The button is in the middle and the delay box is on the top. I used the large button. I also used a three step. One for burnout RPM, one for Stage RPM and one for the high RPM limit.
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