Is there anyway we can replace certain group of Instrumentation communication with either Profibus or Field Bus? My Intention is to run only Profibus cable or something like that which will run at the instrument and we will get information though this communication cable, but do not know how? I know we need power to transmitters and like that (i mean 2 wire - loop powered) but is there any device who can run directly using Profibus or Field bus concept to save cable cost and like that.. Sorry if you cannot understand my concept

 

The short answer is YES. You will need field instruments that are capable of running Profibus-PA and then you can use Profibus cabling. Or if you select field instruments that run Foundation Fieldbus, you can use Fieldbus cabling. Both MAY save you money on cabling, but the real benefits are not the cable savings. The real benefits of the Fieldbus concept is to distribute intelligence to the field instruments and to make them independent of the control system. This can only be accomplished with Foundation Fieldbus that is capable of
running about 80-90 percent of the control loops in field instruments, thereby freeing the DCS (control system) from the time-critical load of loop processing. It has been proven many times that control loops closed between field devices on Foundation Fieldbus are more responsive and give superior control performance compared to loops closed between field devices and a controller. This is discussed at length in my books on Automation Networks and Fieldbus systems.

Dick Caro
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Richard H. Caro, Certified Automation Professional, CEO, CMC Associates,
2 Beth Circle, Acton, MA 01720 USA
E-mail: RCaro[at]CMC.us
Web: http://www.CMC.us
Buy my books:
http://www.isa.org/books
Automation Network Selection
Wireless Networks for Industrial Automation
http://www.spitzerandboyes.com/Product/fbus.htm
The Consumer's Guide to Fieldbus Network Equipment for Process Control
Buy this book and save 50% or more on your next control system!!!
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