Yokogawa Electric Corporation

Dresser, Inc.

Yoji Saito

Kazuhiro Hashizumi

Alex J Legere

Hongli Du

Hirofumi Takahashi

Masanori Noguchi

Isao Uchida

Satoru Ochiai

Koji Demachi

Takashi Nishijima

Toshiki Ogawa

Masaaki Nikkuni

Seiichiro Takahashi

Tetsuo Hoshi

Toshiro Tomita

The present invention provides a field device whereby the device's additional information can be transmitted wirelessly without the need for battery replacement or external wiring. The present invention also provides a field device whereby the firmware of a wireless module in the field device can be developed at minimum cost and whereby it can be made easy to link the firmware to applications, such as an asset management system, on the host system side. The field device in accordance with the present invention is installed in a plant, factory, or the like, connected to a higher-order distributed control system through a signal line, configured to input or output 4-20 mA signals, and comprised of:

Field device and method for transferring the field device's signals

A signal relay device, a communication network system and an operation system include: a standardized logic interface conversion unit for judging a control system type or a device type and converting a signal to a signal appropriate for a communication network; or a device side logic interface conversion unit for converting a signal from the communication network to a signal appropriate for the control system type or the device type. An operation monitoring station includes a an advanced control block for the control system or the device and transmits a control signal to the communication network.

Signal relay device, communication network system and operation system

Process control systems may include one or more diagnostic systems and/or processes. In particular implementations, a diagnostic system and process for a field instrument may include the ability to divide a signal input range into a plurality of zones with respect to an input axis or a time axis, measure input response characteristics for a zone with the field instrument, and store measurement data points for the zone in memory of the field instrument. The diagnostic system and process may also include the ability to transmit the measurement data points for the zone to a host application and, while transmitting the measurement data points for the zone, measure input response characteristics for a second zone with the field instrument.

Off-line diagnosis system

A memory updating system for a field device involves a fieldbus, one or more field devices that incorporate a nonvolatile memory and are connected to the fieldbus, a host system that is directly or indirectly connected to the fieldbus and transmits an updating instruction and updating data to one of the field devices in order to update the nonvolatile memory of the field device, and a current control circuit that controls a current provided from the fieldbus. The current control circuit increases the current provided from the fieldbus to a value greater than a normal value before the field device erases data stored in the nonvolatile memory, and returns the current provided from the fieldbus to the normal value after the field device completes the erasing of the data stored in the nonvolatile memory.

Memory updating system for field device

A valve positioner and current-to-pneumatic converter having a reduced number of components and increased current allocation to a current-to-pneumatic conversion module therein, wherein current signals containing set point information are applied to a digital computation circuit through input terminals which carries out control computation to control valve openings so that each valve opening agrees with each corresponding set point; and a current-to-pneumatic conversion module converts the control outputs from the digital computation circuit into pneumatic signals; and further comprising a power voltage generator that generates an internal power voltage from the current signal; a variable impedance circuit connected in series to the power voltage generator and in parallel to the current-to-pneumatic conversion module; and an impedance control circuit that controls the impedance of the variable impedance circuit.

Valve positioner and current-to-pneumatic converter

Growing community of inventors

Musashino, Japan

Yoji Saito