Dave Harrold


Energy, Power April 26, 2016

Control system power and grounding forensic exam aids reliability

Before replacing an aging control system, the engineer willing to conduct a forensic examination increases the odds the new system will perform reliably. See power and grounding tips.

By Dave Harrold
Info Management October 1, 2005

Utility Leverages MES for Compliance

Ontario, Canada's drinking water regulation (part of the country's Safe Drinking Water Act) was enacted to ensure that water intended for human consumption is free of disease-causing organisms or unsafe concentrations of toxic chemicals or radioactive substances. The regulation also stipulates that drinking water should be aesthetically acceptable and palatable—taste, odor, turbidity, and...

By Dave Harrold
Asset Management September 1, 2005

6 Asset Management Myths

Most companies agree asset optimization is a good thing; many strive to optimize each and every asset—or at least achieve a broad level of optimization across all assets. The problem is you can't optimize something until you first are able to measure and manage (control) it. Through this process we get the concept of asset management.

By Dave Harrold
Machine Safety April 1, 2005

Process Safety What are the Odds?

Within process plants, layers of protection (LOP) include relief valves, rupture disks, dikes, and a safety-instrumented system (SIS). SISs are specially engineered solutions that are continuously online and expected to instantaneously take action to mitigate any detected unsafe process events. But with weeks, months, or even years between unsafe events, what can be done to minimize the probabi...

By Dave Harrold
Industrial Networking January 1, 2005

Avoid electrical ground loops

Ground loops (also referred to as "noise") in an electrical system result from unwanted current that flows in a conductor connecting two points that are supposed to be at the same electrical potential, but aren't. When this condition occurs in instrumentation loops, adding electrical current or voltage to, or subtracting it from, the instrument signal is often detrimental to control system perf...

By Dave Harrold
Ethernet August 1, 2004

Intelligent Data Access = Profitable Operations

Deployment of standards-based, digital fieldbus networks has been steadily replacing combinations of proprietary local- and remote-I/O networks over the past decade, ushering in the plant floor information age, where flattened, streamlined organizations, offer the potential for everyone in the corporation to better understand the details of what does and doesn't make things work.

By Dave Harrold
DCS, SCADA, Controllers May 1, 2004

Historian Holds Key to Performance

Originally configured to gather a few hundred critical parameters across a 1,000-acre plant and display results on seven operator interface terminals, Aughinish Alumina's OSIsoft PI (pronounced pie) historian software now serves as the operational data repository for more than 25,000 measurements; interfaces with other applications; and provides results to operators, management, and laboratory ...

By Dave Harrold
Process Instrumentation and Sensors April 1, 2004

Innovation Transfer

Over the past two decades, significant socio-economic changes have occurred to impact how the life-science industry discovers, develops, and delivers new products. Most significant among these changes are: For the by life-sciences industry the direct consequences of these include skyrocketing R&D costs, especially in the discovery and development of more complex molecules and subsequently m...

By Dave Harrold
Mechatronics and Motion Control March 1, 2004

Are You Satisfied?

Determining which control and automation companies provide the best products and services is a lot like trying to "win big" in Las Vegas. Just when you think you have a system that's working, something (or everything) changes and the house wins it all back—and then some. In the world of control and automation, circumstances that often change, or at least influence, the quality and availab...

By Dave Harrold
I/O Systems, I/O Modules March 1, 2004

Preparation Pays Off

Anyone who has painted a room or a house, hung wallpaper or tile, or planted flowers or a vegetable garden understands the importance of preparation. Unless the surface or soil is properly prepared, the most expensive paint, wallpaper, or plants won't yield the desired results. The same is true with control and automation systems.

By Dave Harrold
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