Selecting Position Sensors in High Vibration Environments – the Do’s and Don’ts

Machines that are subject to harsh or prolonged vibration present challenges for many components – none more so than position and speed sensors. This article lists 10 simple rules for design engineers when selecting position and speed sensors that must cope with shock or vibration.

There are many examples of harsh shock and vibration environments: off-road vehicles, airborne avionics and mining equipment. There are also some less obvious examples such as pumps and refrigeration plant, where the vibration is less extreme but persists over many years. Of course, characteristics will vary from application to application but generally all environments with vibration or shock can present significant problems for electrical control systems, particularly position and speed sensors.

The imaginary hacker

Under recent economic conditions, it is understandable that a control-system cyber-security audit is not the top priority for many plant operators. Less staff due to layoffs and deferred maintenance can present a clear, tangible threat to operations. Too often, “the imaginary hacker,” discussed in many papers and blogs, is often considered as a non-credible threat. No matter how many blogs, magazine articles and white papers are written, a real credible threat to a refinery or petrochemical facility from some vague person or organization seems “imaginary” to those controlling plant budgets.

Web-enabling Your PLC

Enough has been written during the past couple years to convince most plant managers of the benefits of connecting plant floor equipment and processes to the Internet or Intranet.  So, now that we’re all convinced of the benefits of web-enabled automation, what pieces and parts are required to put this technology to work?  The basic parts required for web-based data acquisition and control are:

•  an interface to the machine or process to be monitored or controlled via the web (network) connection;
• a web server to make the desired display and/or control pages available to the remote browser or client; and
• a data service or interface to handle exchanging data between the local machine/process (server) and the remote system (client).