主权项 |
1. A positioner receiving a supply of an electric current through a pair of electric wires from a higher-level system to generate its own operating power supply from the electric current that is supplied, and controlling a degree of opening of a regulator valve in accordance with a value of the supplied electric current, the positioner comprising:
at least one control sensor measuring a physical quantity used in controlling the degree of opening of the regulator valve; at least one non-control sensor measuring a physical quantity used in other than controlling the degree of opening of the regulator valve; a power supply controller controlling the at least one control sensor and the at least one non-control sensor as sensors to which power may be supplied, excluding an opening sensor detecting the degree of opening of the regulator valve, the power supply controller controlling whether or not power is supplied to each individual sensor to which power may be supplied, so that a plurality of sensors to which power may be supplied do not operate simultaneously, and reading in, as power supply statuses, measured values from the sensors to which power may be supplied, wherein: the at least one control sensor and the at least one non-control sensor include a specific control sensor as a reference sensor; a cycle time for the supply of power to each individual sensor to which power may be supplied is set based on the cycle time for the supply of power to the reference sensor; and the cycle time for the supply of power to each individual sensor is set individually for each as a function of the cycle time for the supply of power to the reference sensor. |