Sensors, Actuators

Sensors, Actuators March 1, 1998

Keeping the Pressure On Pressure Instrumentation

This is the first installment of a five-part series on Process Sensing. Smart sensors will appear in May. Others include temperature sensing (June), flow measurement (September), and level sensing (November).Temperature may be the most measured process variable, but pressure sensing devices may be the most ubiquitous.

By Dick Johnson, CONTROL ENGINEERING
Sensors, Actuators March 1, 1998

New Technology for Moisture Measurement

Berkshire, U.K.— The 4112 Dew Point and Temperature Transmitter measures moisture in processes where it has been previously impossible to do so because of temperature limits, contaminants, and harsh environments. The sensingelement combines a moisture sensor and platinum RTD at the probe tip and is designed to operate continuously at temperatures up to 165 °C.

By Staff
Sensors, Actuators February 1, 1998

Scanneriess Wet-End Web Measurement

Cupertino, Calif. —SpectraFoil is a full-sheet measurement sensor for the wet end of the paper machine and the FullWeb Advanced Systems Technology (FAST) control package. Rather than employ a scanner, the sensor provides instantaneous cross-direction (CD) and machine-direction (MD) water weight measurements.

By Staff
Sensors, Actuators January 1, 1998

Intelligent Valve Positioner

Foxboro, Mass.—Foxboro's I/A Series Intelligent Positioner is said to extend the benefit of the I/A Series system to the valve, fully "closing" the intelligent control loop. The device communicates setpoints to the valve as a direct digital signal, without the imprecision of analog transmission and without the cost or complexity of separate multiplexers.

By Staff
Sensors, Actuators January 1, 1998

Fisher-Rosemount, ARCO-Alaska Installing Foundation Fieldbus on Oil Rigs

Fisher-Rosemount recently contracted with ARCO-Alaska Inc. to install the world's first F OUNDATION Fieldbus on an oil production site at ARCO's West Sak facility on Alaska's North Slope. Expected to begin this past December, the project's initial phase includes 50 oil wells.

By Staff
Sensors, Actuators January 1, 1998

New Ultrasonic Flowmeter Handles Custody Transfer Applications

Krohne's new multichannel ultrasonic flowmeter is accurate and reliable enough to be used for the first time in custody transfer applications. The petroleum industry demands this type of application, but has traditionally had to use turbine meters, which are costly and require cleaning and calibration.

By Staff
Sensors, Actuators January 1, 1998

Shutdown Actuator

San Carlos, Calif.— ESD Series actuator is a highspeed electric device that can open or close valves in response to emergency signals within 0.7 sec. The device can respond to signals for various sensors including seismometers, toxic gas, flowmeters, pressure gages, and temperature monitors. Features low maintenance operation and a battery-backup (Ni-Cd) system .

By Staff
Sensors, Actuators June 1, 1997

Diagnostic capabilities accelerated with DeviceNet and PC Control

BUS OF THE MONTH: DeviceNet

By Control Engineering Staff
Sensors, Actuators September 1, 1996

Sampled Control, Better Results With Less Data

Control Engineering classic: In this article, the consequences of performing feedback control with sampled rather than continuous data are examined.

By Vance J. VanDoren, CONTROL ENGINEERING