Inspired innovators live on in their enduring discoveries. Such is especially true for John G. Ziegler, 88, the father of modern process control loop tuning, who died Dec. 9, 1997, at his retirement home in Scottsdale, Ariz.A literal cornerstone of the control field, Mr.
The southern tip of California's Marin county is separated from the city of San Francisco by the most famous mile-long strip of steel and concrete in the world. Yet, within a 10-minute walk of the Golden Gate's Marin terminus begins a county-wide network of California Wildlife Service signs warning against mountain lion attacks.
Foxborough, Mass.— GraphWorX32 is an virtual ActiveX container for HMI/SCADA applications. The scalable software is a fully compliant OLE for Process Control (OPC) application and is a new development using Microsoft technology. GraphWorX32 uses Visual Basic for Applications (VBA) 5.0 scripting language to create reports, recipes, and perform calculations based upon event-driven requests.
More users, system integrators, and manufacturers of control hardware and software are realizing the benefits of digital networks at the sensor, device, and fieldbus levels.In this kickoff of the "Year of the Network" series, Control Engineering asked leaders associated with 12 major industrial networks to reveal growth projections, ideal applications, views on standards, and future out...
BUS OF THE MONTH: WorldFIP
Boeing Explores Development of ‘Smart’ Transducer Bus Lee Eccles of Boeing Commercial Airplane Co. began his presentation in the ‘Use of Automation to Enhance Productivity in the Aerospace Industry’ by asking the question ‘why bother?’ In structural sensing and testing of airplane wings and fuselages at Boeing, a lot of effort goes into simply setting up the test. Structures for destructive testing of a wing or testing flight-control actuators require huge setup times.
BUS OF THE MONTH: LonWorks
Conveying understandable process information to an operator requires more than dazzling HMI graphics in real time.
The National Electrical Code (NEC) defines a ground as ‘a conducting connection, whether intentional or accidental, between an electrical circuit or equipment and the earth, or to some conducting body that serves in place of the earth.’ A ground loop can be defined as any objectionable current flowing in a circuit’s ground or return path. Here is a short guide that will help identify possible sources of ground loops in your electrical systems and how to solve them. The simplest ground loop involves connection between two different earth grounds as shown in the top figure. With earth ground #1 at one potential, and earth ground #2 at a different potential, a ground loop current will flow in the loop as indicated.
BUS OF THE MONTH: DeviceNet