Answer / rafaqat

Profibus is used to make comunication between PLC & other
devices like inverters etc. this is siemens technology
mostly used on siemens PLC, while Allen Bredly use DH+,

also some other protocoles are also available in the market.

what is differences between singal acting and double action valve

1 Answers   Carlo Gavazzi, Welspun,

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please send the hpcl (instrumentation) model placement papers to my mail....

9 Answers   HPCL, Invensys, IOCL, ONGC,

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WHAT IS THE CAM POSITION IN CONTROL VALVE POSITIONER ? WHY IT IS USED?

0 Answers  

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what are the problem's will accure in dcs or plc hadware and what are the solution for it?

2 Answers  

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1.what is the effect of vapour presuure in orifice plate flow measurement 2.which is more effective 2 pressure sensors or one single differential pressure sensor in orifice plate measurement 3.how to design a v/i converter and i/v converter 4.how many type of thermocouple are there 5.how many leads are there in thermocouple measurement 6.how pressure sensors are connected in level measurement in differential pressure method 7.what is the output of capacitive pressure sensor (ac or dc),how its o/p is signal charactarized 8.what is the physical meaning of discharge coeeficient,why it is calculated,orifice plate what is its value,why it is less than 1,Q at upstream is equal to or not equal to Q at downstream of orifice plate why?what is vena contracta in orifice plate 9.why rotameter is called variable area flowmeter,it can measure flow even if area is not varying,why it is made tapered 10.design a 10 bit counter ,which counter you will prefer 11.how to remove self heating error in RTD 12.which is more sensitive pt100 or pt50 13.why thermocouple are connected in parallel 14.what is lead contact error in RTD,how to avoid 15.what is P,PI,PID,PD controller,why there is no ID controller 16.what is override,split range,sequential,ratio,feedforward,cascade controller 17.why we moved from SR to JK and then JK to master slave JK flipflop,give correct reason 18.how to measure level of a closed container which contains vapour and liquid,remember no vapour gas should be leaked,so ultrasonic and capacitive is not an option,design another method 19.how to design horse race counter including sensors and signal conditioning element 20.what is bevelling

0 Answers   BARC,

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What is the purpose of the analyzer in petrochemical plant?

0 Answers   ENI, Lakshmi Machine Works,

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FOR CO/CO2/O2/NOX applications which of the following manufature is best? and what is the basic principle of gas analysers? ABB/YOKOGAWA/EMERSON/SIEMENS/TELEDYNE/THERMOFISHER

4 Answers  

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why is negative range given to measure the steam drum level

2 Answers   Jindal,

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What is inside the PLC panel? How does instruments communicate to DCS computer via PLC? What is the type of wiring in PLC connections? Please answer... Thanks

1 Answers  

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How to find out turn down ratio of Pressure transmitter?

1 Answers  

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The wire is disconnected from the fuel gauge sending unit (bimetallic gauge). A voltmeter connected to the wire reads a pulsating 5v. What does this indicate?

3 Answers  

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what is the diffrence between plc&dcs

4 Answers   HCL, Hindustan Zinc,

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