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May
28

Deminar #4: On-line Process Control Lab Access and Use

On-line Process Control Lab Access and Use Deminar

I invite you to play the Recorded Deminar and download the presentation slides.

The single, cascade, and feedforward loop labs are representative of 99% of the industrial processes if you scale the process gains, lags, and delays so that the controller gain setting is approximately the same and integrated errors are multiplied by a correction factor that is ratio of the actual to modeled process reset time setting. The main exception is exceptionally fast processes (e.g. liquid pressure and compressor surge) where the PID module execution time must be less than 500ms.

Note that the process control lab interface uses the term “delay” for “dead time” (time after an input change to the start of the output response) and “lag” for “time constant” (time from the start of the output response to 63% of the final value of the output for self-regulating processes). Note also that process Lag 2 should be set to match the largest time constant in the process. For integrating processes, the integrating process gain has units of %/sec/% or 1/sec and is the ratio of the process gain to process Lag 2. For runaway processes, process Lag 2 is a positive feedback time constant.

The access within companies to this new website and online process control labs may be blocked. You may need to request your Corporate IT security folks to permit access and a remote desktop connection. Also please be aware the registration details and credentials (connection address, username, and password) for the remote desktop connection may end up in your junk E-mail folder since the registration message is from a new website and may be viewed as unsolicited.