P.C.M. is an abbreviation for Positive Close Mode. It is a mode which can be selected to close a gate up against an end stop. In this mode the gate will slow down normally; then continue to run until it strikes a physical end stop. If there is no end stop the gate will continue to run for approximately 350mm and then stop. Its main use is to ensure that a gate is always closed to an exact position so that, say, a magnetic limit switch will make reliable contact.
WARNING: Care must be exercised in this mode because the gate will not reverse from the instant that the gate starts its slow down ramp till it is fully closed. Thus any object in this region of the gate travel will be trapped. It is highly recommended that infra red beams are fitted if this mode is selected. The IR beams are effective up to the point that the gate stops.