Talk:SCADA

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[1]Something completely different: I noticed that in fact all external links point to commercial websites and can be seen as advertisements or commercial links. It is safe to assume this is not allowed or should not be allowed. Ramkay's link ( www.m-indya.com/scada/ further down on this page ) is the only one I can see as useful for this article --HaPi 13:29, 15 April 2007 (UTC)

Hi HaPi, Do you think we should add this link in the external links? --Ramkay

Nope. I don't think the m-indya.com link should be added. (Requestion 06:12, 30 April 2007 (UTC))
See [1] and [2] for reasons why adding the m-indya.com link is a bad idea. (Requestion 21:24, 30 April 2007 (UTC))

Correct Gadz, I noticed it and I didn't change it. Probably the differences between PLCs and RTUs are becoming less clear in time? I think Communications between centres ("SCADA" or "DCS") becoming faster and simpler, protocols like ICCP, make the difference between scada or dcs less important and -indeed- the whole thing could as well be called Control Systems. --HaPi 20:51, 10 July 2006 (UTC)

oh, by the way, I removed all links that can easily be found by googling. I humbly apologise if by doing so I hurt someone's business, if I removed a link from a sponsor of this site I'll put it back personally. --HaPi 20:51, 10 July 2006 (UTC)

Also , the article seems to merge the definitions of SCADA and DCS. Traditionally SCADA consisted of RTUs and Master Stations over Geographically Distributed areas. It was defined as a Supervisory Control And Data Aquisition system which included both RTUs, Master Stations and the communications networks in between. These days a few Marketing gurus from companies like Wonderware and Citect have branded the HMI's as SCADA.

PLCs were more associated with DCS systems and were closed loop systems. Feedback from field IO was expected to be immediate where SCADA was traditionally expected to log field changes and send them back in bursts (though not always the case).

Today Control Systems combine the technologies from SCADA systems, DCS systems and internet technologies to form all sorts of hybrid solutions that have more do to with engineering control system solutions and less about the technical definitions that gave birth to these technologies.

In essence SCADA ain't SCADA anymore. It would be better to call them all Control Systems.

Gadz


Modbus is not a SCADA product, it is a communication protocol like Proflibus. Wonderware is a better example of a SCADA product

  (Gary84 said -- Wonderware is more of an HMI product)
I think Gadz and Gary84 are missing a few details: SCADA is a design philosophy, not a product. You don't go to a store and buy a piece of SCADA. Toward that end, ModbusRTU is a protocol. It can be part of a SCADA system if it is used that way. The whole thrust of a SCADA sytem is that one is supposed to use Supervisory commands and data. Thus, control loops are not meant to be closed through a SCADA system. They're meant to go no further than the RTU. Upon loss of communications, the RTU is intended to continue working with its control loops and perhaps to execute some sort of local control strategy to keep product moving or perhaps to safely shut down. Also, I agree with Gary84, Wonderware is an HMI, an element of a SCADA system, not a "SCADA product". Scadateer (talk) 17:24, 9 May 2008 (UTC)


Contents

[edit] *Nice* work

I've just inlinked this page from NOC; please let me say that this article, while on a topic that's a touch esoteric, is *very* well written. In today's environment, I'm not sure you'd wanna feature it (no sense giving the Bad Guys<tm> any extra ideas, but still... Nice job, all. --Baylink 07:02, 30 Jan 2005 (UTC)

[edit] Possible copyright infringement?

Look at this page: http://ref.web.cern.ch/ref/CERN/CNL/2000/003/scada/

Please apply the {{copyright}} template to the article if a copyright may be infringed. -- Fingers-of-Pyrex 22:31, 2005 May 15 (UTC)

There's also parts copied straight out of http://www.divergentcontrologic.com/SCADAMain.htm. The rules are "Wikipedia content can be copied, modified, and redistributed so long as the new version grants the same freedoms to others and acknowledges the authors of the Wikipedia article used (a direct link back to the article satisfies our author credit requirement)." As far as I know this article doesn't give any credit back to the author. I suggest putting this article up for speedy deletion. Rejnal 03:33, 31 January 2006 (UTC)

Copyvio? [3]. John Vandenberg 13:40, 23 June 2007 (UTC)

[edit] Glib ?

In Manufacturing SCADA usage is driven by cost saving achieved through automation. Most SCADA packages can deal with many different controllers so perhaps just quote Control Industrial Processes such as Civil Engineering; Trafic Lights/Mass Transit; Process Control (Automation of Manufacturing)etc. Again in Manufacturing SCADA systems are used to bring together several autononimous controllers (perhaps from different manufacturers)and present the process information to operators in a concise standard manner; independantly of the controllers own interface. Use of TCP/IP as a communication link is on par with the use of RS232, RS485 links or optic fibre. Also note that OPC is fast making SCADA front ends easier to implement across open systems; again the underlying communication architecture is irrelevant.

[edit] Clarity of definition

I came to this page because I've never heard of SCADA before. I'd like to finish reading the first couple sections and have some idea of what is SCADA and what isn't SCADA. All computers are control systems. All computers do communications. All computers have inputs and outputs. What special and unique features are required to earn the SCADA moniker?

Is it the fact a set of industrial and/or scientific tools are involved? Could email software be considerd SCADA? Could an SNMP controller? What about a home network using X10 devices?

Ebyrob 01:41, 2 March 2006 (UTC)

I agree. Reading this, I felt like I was reading about Ice: "Ice is cold. Ice floats. Ice has fourteen phases:... Ice can be an insulator, in the following ways..." and the article never got around to mentioning that ice was the solid phases of water. The article says a very great deal about SCADA, but not much about the definition of SCADA. --TreyHarris 12:42, 22 March 2006 (UTC)
I've rewritten the opening paragraph. I hope this fixes the problems you have understanding what a real SCADA system is. Scadateer (talk) 17:24, 9 May 2008 (UTC)

[edit] External links

All those links make the article look like an advert. Are they all really necessary? Kevin 07:31, 16 May 2006 (UTC)

I agree, and these links are not necessary. I'll take them out in a few days, unless someone comes up with a good reaso to let them be. --HaPi 12:15, 12 June 2006 (UTC)


I think this is a very good discussion of SCADA though as usual tending to blur SCADA and DCS - may be what it requires is a 'simple' explanation at the top - I came to this page after checking the DCS page and adding what I hope may be a clarifying difference between SCADA/PLC and DCS - and yes I work in a job where I have to deal with both SCADA/PLC solutions and DCS solutions.

DCS implies a top down factory wide solution to a process. The process is whatever the factory as a whole makes (ok in refineries there will be autonominous units that equate in practice to seperate factories). Alarms and reports are generated by the DCS

SCADA/PLC implies a bottom up solution - frequently ending up in an accidental fatory wide solution. Alarms are generated by the individual PLC's. Reports are generated by querrying the PLC's

Petedtm 21:05, 9 August 2006 (UTC)

This link is a knowledge base on Scada www.m-indya.com/scada/ . I am sure some may find it useful. If anyone else agrees then this link can be added to the external links? ramkay

Hello Ramkay. You asked this same m-indya.com link question up above and the answer is no. (Requestion 21:24, 30 April 2007 (UTC))

[edit] Future trends in SCADA

Is this section really appropriate for an encylopedia? It seems like someone's predictions and opinions and not what Wikipedia is about. Also, I don't agree with it but lets not argue opinions here. -Crunchy Numbers 16:59, 20 September 2006 (UTC)

I agree. I feel this section ought to be deleted. One doesn't read an encyclopedia for future prognostications. Scadateer (talk) 16:58, 9 May 2008 (UTC)

[edit] North America?

What North America means here ? Mexico, USA and Canada ? Or just Canada and USA? Or just USA?

[edit] Systems concepts - Vendor list

The Systems concepts section has a list of vendors that I cleaned up. (Disclaimer: I have a relationship with GE Fanuc and I want to make sure I did it in a NPOV way.)

I undid the addition of LABTEKNIX to the list of SCADA suppliers. What is it? Google, Yahoo, and Microsoft Live searches find no references.

I alphabetized the list, added Wikipedia links where appropriate, and moved SUPCON and Telvent from PLC hardware/software to HMI software list.

The lists seem to be listing companies and not products. Given that, I have a couple of questions:

  • DirectLOGIC seems to be the product rather than the company. Is Automation Direct the company?
  • Adroit seems to be the product rather than the company. Is CIMNET the company or is it now fully part of Wonderware?
  • Citect is now part of Schneider Electric. Is CitectSCADA still sold by Citect as a company or is it just sold by Schneider?

Note that it might be more appropriate (less controversial) just to remove the list of vendors.

--Ishi Gustaedr 16:17, 20 August 2007 (UTC)

[edit] SCADA are not control systems

SCADA systems are not control systems, but the article hints as such. The word "control" in SCADA is qualified by "supervisory". I just hope some expert rewrites this page. Hi pedler 09:35, 28 September 2007 (UTC)hi_pedler

Not necessarily. My company represents a SCADA system that can do complete control using internal logic to eliminate the need for PLC's. Local RTU's can do real time control at the site as well as offer the near real time supervisory control from a remote location. They can send and receive digital and analog signals based on programmed logic to control most systems attached to it. Utilitysupplies 21:02, 28 September 2007 (UTC)
The definition of SCADA is getting very muddled due to an excessive number of mainstream articles referring to all industrial control systems as SCADA. However, the generally accepted definition of SCADA is a system which uses predominantly open loop control (in other words, a control system with a human in the middle) over slow speed links. Closed loop controls are often found in a DCS. The closed loop controls in a DCS are generally found on a campus, where communications via a LAN are common. The open loop controls in a SCADA system generally have very slow reaction times (typically measured in fractions of an hour or more). That is not to say that DCS will never have open loop control or a SCADA system shouldn't have closed loop control. It merely indicates an overall design philosophy. --Scadateer (talk) 22:50, 27 April 2008 (UTC)

[edit] Europe versus The World

It is not immediately obvious from the article where the statement "In Europe, SCADA refers to a large-scale, distributed measurement and control system, while in the rest of the world SCADA may describe systems of any size or geographical distribution" comes from. I have read about the differences in protocols (IEC vs. DNP3) between different regions, but this statement seems to refer to the scale and terminology used in different places. I don't know of any references that support this, and every time I try to search around about it, it all comes back to (essentially) "the Wikipedia entry says so" .

If anyone (perhaps the contributor who added that statement) knows, a reference would be nice, or some explanation. —Preceding unsigned comment added by 68.222.69.25 (talk) 02:15, 18 February 2008 (UTC)

I fixed the assertion. Most of the differences between Europe and North America are a matter of which standards are in use, not conceptual issues such as what SCADA means. Scadateer (talk) 16:56, 9 May 2008 (UTC)

[edit] SCADA as a hosted service

In the Trends in SCADA there is a paragraph on SCADA as a hosted service. Can we get a good reference that identifies this as trend? I know some vendors have already been doing this for a long time through their services departments rather offering it as a product. I realize the content may have initially appeared as an advert, but I think there's some worth in the paragraph. I tried to add some balancing information, but it's not well sourced. --Ishi Gustaedr (talk) 13:31, 30 May 2008 (UTC)