Patent ID: 8872486
Filing Date: 2014-10-28
Classification: G01R,G05B,G08C

Abstract:
1. A field instrument comprising: a current value adjustor adjusting, according to a measurement value, the value of current flowing through a two-wire transmission path; a first power supply unit generating a first power supply from the current flowing though said transmission path; a second power supply unit receiving a supply of power from the first power supply unit and generating a second power supply; a processing unit receiving a supply of power from the second power supply unit and carrying out a predetermined processing operation; a current control element provided on a supply path of current flowing from said first power supply unit toward said second power supply unit; and a load circuit provided on a branch flow path of current flowing from said first power supply unit toward said second power supply unit, wherein one end of the branch flow path, which is connected to the first power supply unit, is connected to one end of the load circuit, and another end of the branch flow path, which is connected to the second power supply unit, is connected to another end of the load circuit, wherein the branch path having the load circuit branches out form the supply path and runs separately from and in parallel to the supply path between the first power supply and the second power supply, and serves as a secondary path to the supply path, wherein said processing unit comprises a current control element controller controlling the element status of said current control element as necessary and causing the current flowing through said supply path and toward said second power supply unit to branch to said branch flow path in the amount required to operate said load circuit, and wherein said processing unit comprises a controller enabling control of an element state of said current control element in a case when said processing unit determines that it does not have an effect on the processing operation of said processing unit to cause the current, which flows through said supply path from said first power supply toward said second power supply, to branch out to said branch flow path.