mpo55Danfoss MP 55 Differential Pressure switches delay of relay 90 sec. 060B017291 Adjustment Cut out for falling pressure. Ambient temperature -40 - 60 °C. Ambient temperature -40 - 140 °F. Ammonia application No. Approval CCC, CE,The MP55 Melting Point System measures melting point and slip melting point automatically in the range from room temperature to 300°C. Save time by measuring up to 3 melting point