why the derivative in PID is always set to zero?

3 Answers  

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why do we use 4-20mA as o/p and why don't use 0-20mA or 5- 21mA?

3 Answers  

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What is shriking and swell effect for a boiler ?

1 Answers  

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What is the difference between conductive lined pipe and conductive unlined pipe? Why do we see that?

0 Answers   Process Control Technologies,

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why I need valve guard and whats different between guard and positioner ??

0 Answers  

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What is the function of solenoid valve in on/off & shutdown valve and why it is not used in control valve normally?

0 Answers  

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what is the difference between transmitter and smart transmitter ?

4 Answers   Aditya Birla,

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1.what is the role of proportional comtroller in pid controller?2.How do u calibrate the control valve?

3 Answers   Bently, IOCL,

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In which principle Woodward Governor 505 work in power plant? What are the input of Woodward governor 505

1 Answers  

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what is loop1 and loop2 in MTS LT?

0 Answers   SPGC,

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If I installed wrong directions orifice plate then what showing value d.p transmitter?

2 Answers   Forbes, STS,

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any body tell me ,contol valve has how many cheractristic? explain it.

6 Answers   L&T,

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