Answer Posted / vikram budhiraja

A process variable can be transmitted (as an analog signal) over a pair of wires either as a voltage or a current.

A current (milliamp) analog signal is preferred in control systems over voltage because the current in a loop cannot be different at the generating end and the receiving end regardless of the length of the wire carrying the signal.

On the other hand a voltage signal suffers a drop ( IR loss) depending on the length of the wires carrying the signal resulting in error.

What are the different types of thermistors used in industries? How to the operation of typical thermistor?

2026

---

What are different types of control valves?

1660

---

How you calibrate absolute pressure with the calibration range of 0 to 1000 0C Absolute. Please explain the procedure for calibration.

1756

---

What care will you take in the installation of control valves,SCADA,DCS and FOC in Oil and Gas Project?

2168

---

List three types Level Gauges with their working principles

2125

---

How to calibrate an pressure gauge with yantrika test bench?

2945

---

Pressure tx shows 1 mbar but we need 1000 mbar at this process condition .. how can we sort it out .

1743

---

Definition of reverse and acting controllers:

2371

---

State some of balance principle’ advantages?

1226

---

why fuse block is not used for AI signal?

1949

---

why we use cascade control and feed forward control in 3 element drum level control measurement of steam drum .what is cascade and feed forward control system ?give example .

2928

---

2. What is ultrasonic flowmeter?

5152

---

Q- Control problem are mainly classified in _____ types. a-)4 b-)3 c-)6 d-)nono of these Few of them i know is 1- regulator type problem (eg- Air conditioner) 2- tracking problem (eg missile trcking problem) 3- sybernatics 4- optimal control problem

2173

---

any body who gone thru recent iocl interview.INSTRUMENTATION questions. I need.

2537

---

how to relay switch sense the fault?

2661

---