What is the difference between PLC and DCS?

4 Answers   Honeywell,

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A pressure differential gauge type of instrument has a manifold with 2 isolation valves (hp and lp),2 vents(1 each for hp and lp) and 1 equalizing valve. Determine the position of each valve(either fully closed or fully open) when troboulshooting to: 1. zero the transmitter. 2. determine if there is a block in the impulse line. 3. determine if the gauge is functioning properly. The process fluid is water.

1 Answers  

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why we use 4-20 mA to do calibration of the instruments.why we cant use 0-20 mA?

8 Answers   Emerson, IEM,

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Why the ammonia and Nitric Acid level indicators is with millimeter ? and What is the conversion form millimeters that level indicator indicate to weight ?

0 Answers   EHC,

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Is Hart communicator calibration device or communicating device for transmitter?

4 Answers   Yokogawa,

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why the derivative in PID is always set to zero?

3 Answers  

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why we use 4-20 mA for calibration of the instruments.why we cant use 0-20 mA?

5 Answers  

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please help me to get the below mentioned quires,which i have to submit for my client.[INSPECTION TEST PLAN] 1]I.T.P for Calibration of all instrument. 2]I.T.P for SS tubing. 3]I.T.P for Fire & Gas devices. 4]I.T.P for CCTV & telecommunication. 5] I.T.P for loop checking.

1 Answers  

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is manifold required for an integral orifice meter?

2 Answers  

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what is working principle of presure and temperature guage?

4 Answers  

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What do you do as a Engineering person EPC for Sizing&Selecting Control Valve?

1 Answers  

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Can be operate control valve without positioning if yes ? how and why?

4 Answers   Focus,

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