Answer / h v k kumar

simply plc is a controller we can control analog and digital
i/o s but i/0 limit is there in plcs.dcs is nothing but
networking of plcs.EX
plc1+plc2+smart instruments+mc baesd instruments all are
controlled by dcs at a time .ic has redundancy also

Answer / nitin pathak

Actually in todays world there is a very thin line between
a DCS and a PLC,in simple words when the plant process is
controlled with the help of a computer(all the processing
done by the server) is called a DCS and when the process
control is done with the help of stand alone contollers
then it is called a PLC.

Nitin Pathak
Lafarge Cement

Answer / shani_dms

yes ur rite but i want to addition
first plc also has redundancy.

Answer / sharma

the difference between is that we can detect the error in plc
but in dcs we can find the exact point of error.
where the actual problem is.
we can also control the different error at different

where the use of direct action control valve?

2 Answers  

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Which topics are covered in Process Control?

0 Answers   Honeywell, L&T,

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a flow transmitter [range-0-400mbar] connected in process line. please explain me how to calibrate the flow transmitter , & how to do static error

0 Answers   L&T,

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what is the zero elevation and zero supresstion in level measurement, how can use it?

2 Answers   GAIL,

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how to calibrate pressure gauge(we can not able to fixed by pointer screw adjustment and pointer re fixing method)

2 Answers   Nestle, Reliance,

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How will you change the action of a control valve?

1 Answers   CCIE,

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What is standard of DCS panel design?and what is step of DCS panel design?wiring and type of connector(screw or DB connector)

0 Answers  

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I am going to attend a recruitment drive by Schneider in 2 weeks. They have a technical test in the beginning. I would like to know what are the areas i should concentrate on while preparing for the test. My major is Electronics and Instrumentation.

1 Answers  

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how to explain PID?

2 Answers   Jindal,

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why we use impulse line of flow transmitter at 45 deg. angle both side of orifice plate.

0 Answers  

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-/5A. What is the meaning and limitations of this in energy meter constant. It is a 3 phase LT Energy Meter. If this Energy Meter is connected through a CT of ratio 200/5 Amps, then what is the multiplying constant and how its will be calculated.

0 Answers  

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Why trim span ? How?

0 Answers  

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