Answer / carl_ellis

1) Actuator loses air supply or diaphragm leaks

2) Positioner loses control signal input

3) Positioner mechanical feedback is damaged or disconnected

4) Air supply does not meet instrument air requirements,
dirt and moisture accumulate and cause positioner shuttle
valve to stick

5) Stiction - valve internals are sticky, stem does not move
smoothly through its range

6) Poor positioner tuning creates overshoot

7) Mechanical backlash creates deadband that causes poor
control action

How r the calculation of process line mpm.

0 Answers   Bhushan Power Steel,

---

Q-Explain the different load conditions that will produced different offset which may or may not be acceptable to thhe control function

0 Answers   Reliance,

---

How to calibration a control valve?

0 Answers  

---

How to interfacing microcontroller with a DC motor

0 Answers   JJ Tech,

---

TEMPERATURE VARIATION FOR FREQUENTLY.

0 Answers   TVS,

---

what is the deference bitween DCS and PLC SCADA HMI System for Power Process Industry.

1 Answers   UltraTech,

---

what is difference between two wire &three wire pt 100 ?

3 Answers   Jindal,

---

sir,would you please send me the Hindustan petroleum corporation limited papers(HPCL).my e-mail ID is ujjwal_sharma1983@yahoo.com

0 Answers   HPCL, TCS,

---

What is meant by calibration

5 Answers  

---

Explain the difference between differial pressure & delta pressure?

1 Answers  

---

what is the difference between Feedback controller and Feed forward controller. and when it is to be used.

3 Answers  

---

how many types of viberation transmitter and how to calibrate and where use of vibration transmitter

0 Answers   Sabic,

---