Patent ID: 8086175

Claim:
A field device search system comprising: a plurality of field devices, installed in a plant, having a wireless transmitting/receiving capability, and an information terminal having a receiving capability to receive radio waves from the plurality of field devices, wherein the information terminal includes a radio wave receiver, a CPU, a display part, a memory, and a member for identifying one of the plurality of field devices, the memory comprising machine executable instructions stored in a computer readable medium, comprising, a device position checker that checks a position information of the information terminal; a radio wave sensitivity checker that checks a sensitivity of radio waves of the plurality of field devices; a position order logger that logs travel information of the information terminal; a route operator that determines a search route to one of the plurality of field devices; and a position guide viewer and a radio wave sensitivity viewer, wherein as an operator of the information terminal advances in the plant in accordance with the display part, the radio waves of the field device to receive maintenance appear at a maximum level.