Gas air compressor help

admin

I don't know if this is the place for this or not, but I need help with a gas motor powered generator used for outdoor fab work. I need to know how to wire the starter mechanism, so when the air gets low it will automatically start the compressor to build air then shutdown when it's finished. If I hook the starter solenoid up to the pressure switch, what senses the motor firing to disengage the starter. What would you hook up to shut the unit down when it is finished airing up. It has a mode on it now that if you leave it idling the motor will kick to high RPM to build air, then idle back down, but I don't like the noise of it idling for long periods of time when not in use. It must be possible because emergency generators operate like this.
Reply:I think similar arrangements have been built using an intake manifold vacuum switch to sense if the engine is up to running speed or not. I think that either old Buicks or stop and go delivery trucks may have had a feature on this order to restart an engine. You will need a few control devices. An air pressure switch to trigger the  stop engine relay. Also you’ll want to limit cranking time, and delay reengagement of the starter after a no start crank. Maybe an oil pressure interlock to ensure that an already running engine doesn’t get cranked because of an air pressure loss. You could probably build a simple circuit using delay relays. With electronics you have many more options. Look into a cheap programmable device called a “stamp microcontroller”. Build one for me, I want the power washer to shut down after 2 minutes of no use, restart when the trigger is pulled.
Reply:Thanks for the help. I think I will look into the electronics side.
Reply:Might be able to retrofit a cheap remote car starter to do that.  ...well maybe a cheap one won't to the trick, but most have a 'ignition pulse' sence ( to prove engine running, and not grind starter if running )Some have inputs that can be supplied a signal to start and stop the car, operate outputs.Check car stereo and/or accessory shops, they might have one laying around that is just the ticket.