Software tools come to control
15 Jan 2000
Following on from above, Mitsubishi is not the first control vendor to address that grey area between the DCS and the PLC, between process and machine control. Moore Products' APACS system, for example, has been on the market for five years now, and it has recently been enhanced with APACS ProcessSuite (361).
ProcessSuite is a Windows NT-based software package that basically bundles several software tools into the already powerful APACS system. The integrated suite consists of the IEC 1131-based `4-mation' controller configuration software (which is at the heart of APACS' unified DCS/PLC capabilities); Wonderware's InTouch operator interface software; the Scout Internet-based viewing tool; the IndustrialSQL server; and several specific configuration utilities.
* If there is one thing that characterises process control it is arguably the ubiquitous PID loop. Most PID controllers, however, are only tuned over a small process range. `But what happens when the process value moves to another part of the range?' asks Richard Barraclough, who also gives the answer, `the process may oscillate or responses become too sluggish.' His solution is the ExperTune Characteriser (362), a software package that linearises the process (based on empirical results produced by stepping the controller manually through its range) enabling the controller to be optimally tuned across the entire operating range.
* It's not just PID loop settings that can seem out of date, of course. Instrument loop diagrams - not to mention any other engineering documentation - can lag woefully behind the `as-built' condition of a plant. But now that could be a thing of the past thanks to PiSYS, a plant information system that uses a data-centred approach to the production of plant documentation, instead of having to rely on original CAD and P&ID drawings. Already in use at over 100 sites in South Africa, PiSYS is available from Industrial Product Solutions (363).
