"And it doesn't get much simpler than a pair of switch contacts interrupting power to the motor starter coil."
I really hope you mean interupting the signal to the hydraulic valve(s). Controlling a hydraulic system by turning the pump on and off isn't a reliable method of maintaining position or control. Use two adjustable stops on the threaded shaft. Set the prox switch to generate the stop signals at each end of desired travel, and use the shaft stops to hit hard stops to limit travel in case of end of travel switch failure.
Set the hydraulic relief valve to lift when the motor driven frame hits the hard stop.
LarryC
[This message has been edited by LarryC (edited 06-26-2006).]
