A big thank you to everyone who submitted a scada review response. For this year’s scada review we are happy to welcome newcomer SCADAgroup, to welcome back GE Fanuc and to feature the usual suspects of Wonderware, Adroit, Citect, Rockwell and Siemens.
Having read the responses to our questionnaire and asked questions of the reviewers, SIs and suppliers, I would like to share my thoughts on the South African scada environment reflected by these responses.
Scada selection
In motivating a scada project users need to have a good idea of the return on investment that the project offers. To calculate this, the costs need to be known, major elements of which are man-hours for the project lifecycle, licensing lifecycle investment and support costs.
In terms of man-hours per tag the responses span from as high as 1,06 to as low as 0,02. That is a massive 50:1 ratio and while the scope, location and complexity of a project will clearly impact on this ratio, the speed of application of a particular package should be a key factor in software selection.
Depending on the degree of pre-engineering that is performed before software selection, licensing lifecycle investment can also be a risk factor. If the licensing is based on some metric such as I/O count, tag count or display count then users must perform a considerable amount of engineering before being able to determine the required investment level. If the licensing basis is more complex in terms of module, driver and interconnectivity licences then which modules and drivers need to be costed at feasibility stage?
Technology and risk management
Web Services technology has come of age and promises to deliver more up-to-date and relevant plant information to more users and yet it is being ignored by the majority of end-users. Why would this be?
While many systems have their own plant networks for communications, most are connected to enterprise business network at one or more points. In some instances firewalls have been employed for intrusion protection, no-one seems to have adopted intrusion detection.
Few respondents laid claim to the following system design and engineering practices:
* The rigorous application of full-load and failure mode testing.
* The application of formalised configuration and data backup regimes.
* The adoption of internationally recognised alarm management practices.
The lack of these adds unnecessary risk in installed systems and we look forward to bringing readers more information on ways in which to protect their plant systems and valuable data in future issues.
Notes:
1. Some reviewer responses have been edited due to space considerations.
2. The order of appearance of reviews is based on the order in which they were received.
3. A 'No' response to a question does not necessarily mean that the scada system lacks that feature; only that the feature was not implemented in the subject project.
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