Object-oriented HMI system

One of the most common classes of software packages used in automation projects is the human-machine interface or HMI. These packages provide users with the ability to monitor and supervise a control system through a configurable platform. This avoids the need for fixed control panels with dedicated control function interface devices, which present a significant expense in initial device ...

01/01/2000


One of the most common classes of software packages used in automation projects is the human-machine interface or HMI. These packages provide users with the ability to monitor and supervise a control system through a configurable platform. This avoids the need for fixed control panels with dedicated control function interface devices, which present a significant expense in initial device purchase, wiring, and maintenance.

When implementing a project where a new HMI is to be installed, users have three basic categories of systems from which to choose. These include dedicated hardware/software solutions, vendor-specific software solutions, or generic Microsoft Windows-based packages.

Lookout from National Instruments (Austin, Tex.) is a generic, Windows-based HMI system that runs in either the Windows 3.1, 98, or NT environments. It supports many common control networks and has built-in drivers for many of these communication networks. In addition, it allows multiple networks to be active at the same time, even to the point of sharing a communications port. This latter point is important if communication is required using multiple protocols over radio or other limited availability modes.

To implement graphics configuration, Lookout has a large library of standard static- and dynamic-display objects that can be selected by point-and-click. The dynamic-display objects are easy to define by pop-up windows that also aid in editing the objects. A major advantage of this system is once a control object such as a tank level is defined, it can be used in multiple contexts (numeric display, trend, bar display, etc.). Because the system revolves around control objects, database maintenance is greatly simplified.

While the package has a "Snap to Grid" function that aids in object alignment, graphic configuration would be simpler if a zoom function were available. Another problem that can arise during configuration is that Lookout does not support selection of a set of objects for group relocation; the user can only select one object or all objects.

In run mode there is no scrolling within a graphic control window. The software allows multiple panels (windows) to be opened simultaneoulsy but does not support resizing. Thus the objects in a reduced window remain full size forcing the cutoff of portions of the display. As no scroll function exists, the operator must go back to full window size to see these portions of the display. This aids in viewing alarm windows but limits the usability of the multiple window feature."

Because networking and DDE (Dynamic Data Exchange) are important to the application, Lookout supports several standard networks since it runs under Microsoft Windows. Built-in DDE support allows Lookout to share input and output values with other Windows-based packages.

This review is based upon the evaluation package for Lookout for Win32, Version 3.8 (Build 10). Current release for this package is 4.0. A full-function evaluation copy for the current release is available on the developer's web site.

For more information on Lookout, visit www.controleng.com/freeinfo .


Author Information

Contributing Editor, Tracy J. Coates P.E. is a consulting engineer at PCE Engineering, Johnson City, Tenn.




No comments
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by...
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Robotic safety, collaboration, standards; DCS migration tips; IT/OT convergence; 2017 Control Engineering Salary and Career Survey
Integrated mobility; Artificial intelligence; Predictive motion control; Sensors and control system inputs; Asset Management; Cybersecurity
Big Data and IIoT value; Monitoring Big Data; Robotics safety standards and programming; Learning about PID
Featured articles highlight technologies that enable the Industrial Internet of Things, IIoT-related products and strategies to get data more easily to the user.
This article collection contains several articles on how automation and controls are helping human-machine interface (HMI) hardware and software advance.
This digital report will explore several aspects of how IIoT will transform manufacturing in the coming years.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

Mobility as the means to offshore innovation; Preventing another Deepwater Horizon; ROVs as subsea robots; SCADA and the radio spectrum
Future of oil and gas projects; Reservoir models; The importance of SCADA to oil and gas
Big Data and bigger solutions; Tablet technologies; SCADA developments
Automation Engineer; Wood Group
System Integrator; Cross Integrated Systems Group
Jose S. Vasquez, Jr.
Fire & Life Safety Engineer; Technip USA Inc.
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me