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Which is the principle behind making the GPS system work? What is the function and working of a GPS system? What is the role of it in a power plant? This system uses DCS in the power plant. Please give me the details of this topic.

RAJ BAHADUR
raj_bahadur2005 at rediffmail com
rajbahadur2005 at gmail com

One thing that I can think of is satellite synchronization of real time clocks on remote systems

Hi,

GPS receivers calculate their position by timing the signals sent by the constellation of GPS satellites. Each satellite transmits continuous messages containing the time, a precise orbit for the satellite (the ephemeris), and the general system status of all GPS satellites (the almanac). These signals travel at c through outer space, and slightly slower through the atmosphere. A GPS receiver uses the arrival time of each message to measure the distance to each satellite.

As for the uses within a power plant - the only reason I can think of is to ensure that the power plant hasn't moved, as this can make the connection to the first pylon quite difficult. :)

Marc Sinclair

Think harder! Using GPS allows a device to supply its actual location to plus or minus about 3 meters. Sounds like good useful information to me. This is also a highly accurate source for clock time useful perhaps in sequence of events analysis.

Dick Caro
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I'm almost sure it's about getting good time synchronization. One of my customers in the power industry specifically asked recently if we could sync to GPS time.

Eric
www.icpdas-usa.com

Perhaps they use it to determine which phase is A phase? Some of you might get that!

Roy

As some one said, it is used for time sync. The idea behind is to get all devices clock synchronizwd. By synchronizing all devices you may use time stamping function for alarms. It is not necessary to use a GPS system for clock synchronization, you may use any device (PLC) or PC as clock source as a reference and all other devices in control network can be synch with it.  

The main advantage of using GPS is only when you use remote monitoring e.g. web , in this case if you are watching data in a different country than the facility, this means you are in different time zones, and you will not be able to identify the real time of event occourance. By using GPS you can adjust time zone and can have real time information.

BR. 
Muhammad Pervaiz
Superintendant Engineer E&I
Wartsila West Africa, Senegal S.A
P. Box 21861, Ponty Dakar
Off:+221338493990, Cell (Int): +221774502157
Email: muhammad.pervaiz@yahoo.com
Email: muhammad.pervaiz@wartsila.com

We use GPS to help synchronise all the different control systems within the power plant i.e. DCS, power tradings, continuous emissions monitoring and events recorder. Sometimes these drift out by a couple of minutes over time so in event of needed to trend data then it's vital the times are within a few hundred mS sometimes.

Many large plants also plot the location of important peiece sof plant and equipment to help with maintenance scheduling but I guess the former is the reason for fitting GPS onto a modern power plant.

regards

Steve Rose