THE MAINTENANCE SUPERVISOR WAS TROUBLESHOOTING A NEW INSTALLATION OF A BAG PLACER MECHANISM ON A BAG FILLING MACHINE MAKING ADJUSTMENTS TO LIMIT SWITCHES AND RELAYS DURING INSTALLATION OF THE EQUIPMENT. AS HE MANUALLY REMOVED A FILLED BAG FROM THE BAGGER SPOUT, THE BAG PLACER UNEXPECTEDLY MOVED AND STRUCK THE SUPERVISOR ON THE ARM CAUSING A MINOR BACK STRAIN.