|Sat, 22 Mar 1997 22:19:25 +1100 (EST)|
|< firstname.lastname@example.org (William Tarlinton)>|
Sends of the IT industry. This is probably because most SCADA systems actually perform an extremely useful and important role without a huge amount of fuss and bother for long periods of time (i.e low profile IT). Unlike many computer based systems these days that look fantastic, cost a fortune to maintain, get thrown out every couple of years and waste more time and resources than they save (i.e high profile IT). Be wary of this type of sentiment in your organisation. Good luck with your research, I'm sorry I can't point you to any literature on the subject. There are of course consultants and market research people out there, and if you don't have sufficient in-house expertise, this might be something you should consider. Please ask for opinions (and give a some of your own) on some more specific issues as you proceed. I for one would be interested in your decision making process. Regards
Bill Tarlinton Veridian Pty Ltd
|Sun, 23 Mar 1997 10:20:44 +0200|
|< "Michael J Whitwam" email@example.com>|
Hi Joe Bills advice is well written and sound. I too have been involved in SCADA as both customer and supplier, and would like to add the following. When writing the SCADA specification, write it from the point of WHAT ARE YOUR OBJECTIVES, ie. what do you want out of the system. DO NOT tell your potential suppliers "how to suck eggs". Let them do the design, that's what you're paying them for. Getting to clever in a tender spec usually only creates loop holes for the supplier. Here's a classic example. We went to tender for a PLC system that would handle x no of analogues, with a certain accuracy and resolution, isolation etc... The tender was won by a large vendor. We placed the order as per the vendor's offer. Guess what, the system did not work. The vendor had misinterpreted the specs of his own product, and had to supply 2 additional racks free. No technical debate, our tender was simple but explicit. We asked for a SYSTEM. If we had been clever and added a whole lot of detail as to how the job should be done, the vendor would probably have gotten away with it. This does not mean however that you should be ignorant. You should be able to evaluate a vendors offer, even though you let him put it together.
Regards Mike Whitwam Wise Technologies (Pty) Ltd WEB Site - http://www.wisetech.co.za ----------
|Sun, 30 Mar 1997 22:05:01 +0000|
|< "John Cooke, P. Eng." JCooke@planet.eon.net>|
Interesting remarks on SCADA systems. My background has been in SCADA/EMS systems since 1971 (the days of electomechanical one on one tone signalling systems where one RTU talked to one MTU) while mostly working for a 250,000 customer based electric utitility with a peak load of approx. 1GW, with coal and natural gas generation units from 90MW to 375MW which includes some 240KV and lower transmission and distribution facilities from 25KV and down. Although a book could be written on SCADA (sometimes referred to as EMS systems), you may want to consider that costs in Canadian dollars run from $100,000 for simple systems to $6,000,000 for complex systems. If you don't have the microwave, fibre or rf communication infrastructure in place or the necessary building complex or UPS systems, throw in another $2,000,000 ++++ depending on your geography and distance locations!! A system I installed in 1975 came to just under $12,000,000 including hardware, software, some carrier communications, buildings, project management costs, training, overheads and financing requirements. The complex systems usually have significant costs associated with intelligent RTU's, use of advanced application software, project management costs and customized testing procedures needed to verify specifications. The type of communications protocol used to link between various interprovincial and interstate SCADA/EMS (Energy Management Systems) can become very challenging also. The latest being ICCP (Interuitility Control Centre Protocol) now being investigated by the PRovince of Alberta between four major utilities and between provinces all in the name of high speed, real time data e.g. all analogs/critical alarms annunicated in less than 2 seconds skew rate. A concept being followed by some companies to elimanate the conflicts that exist between vendors and users in wheel-barrow SCADA systems are negotiated agreements rather than the traditional tender-short list- bid-questions/answers -contract route with head to head negotiations/arbitration between project managers. Some of the advanced applications that can get really expensive PROVIDED you have the redundancy and amount of analog telemetry are: state estimatation real time load flow economic dispatch var and voltage security constrained dispatch training simulation GBIS or AM/FM real time connectivity graphics transient stability real time analysis operator dispatch/training consoles .................ec. I could go on but a list of some vendors you could investigate that have credibility but variable costs in the EMS arena are: ABB Valmet ESCA and many more European based vendors/utilities such as EDF, Siemens. Their appears also to be substantial trending for larger EMS systems towards DEC, Sun and HP for standardized hardware platforms but my preference for some time based on a proven track record is DEC.
John Cooke, P. Eng. Improvement Team Project Manager Phone 448-3206 Cel 940-2176 Fax 448-3250 (area code 403) EPCOR Utilities Inc., 8743-58 Ave., Edmonton, Alberta, T6E 5W4 firstname.lastname@example.org OR email@example.com CANADA