Answer / senthil

1.During commissioning, we ll do loop checks.it means from
field instrument( PT,TT,FT,LT or switches) the signal is
checked with the DCS.
for example : consider a PT,we ll simulate 4 to 20 mA in the
instrument and the same value should be shown in the DCS also.

2.there are two loops
open loop and closed loop
closed loop for controllers to control the process.for
example, antisurge control in Gas Compressor,Three element
control in Boiler

Answer / g.venkat

There are two loops
1. open loop
2.close loop


open loop using for monitoring and recording purpose

close loop using for controlling the fianal control element

How many types of sensor

0 Answers   Petro Rabigh,

---

Define magnetic flow meter and mass flow meter.

1 Answers   Ramco,

---

kindly tell where orifice,nozzle,air foil,ventury used in flow measurement?

1 Answers  

---

1.what is controller proportional gain 2.what is the controller intergral action time. 3.A proportional plus derivative controller that has a proportional band of 20% and a derivative action time of 0.1 minutes. Construct the shape of the output waveform for the triangular input if the input rises and falls at the rate of 4 units per minute.

0 Answers  

---

applications of 1-5v and 4-20ma?

4 Answers  

---

how to connect 3 wire 4-20 mA transmitter in Plc system PLC system and how explain how the measuring data communicate with plc system.

1 Answers  

---

If hart communicator provide 4-20ma source to any transmitter during the callibration?

3 Answers   Hyundai,

---

what is coriolis principle for mass flowmeter?

5 Answers   ABB,

---

Give an example where you had aproblem on the job, and tell me how you solved the problem. and the finalvoutcome.

0 Answers   American Steel,

---

Dear Sir/Madam,im going to attend Hpcl written exams on feb 17th in instrumentation stream..can anyone send me the HPCL model papers and pattern of HPCL ....i ve not yet attended anything in HPCL...so i dont know how it comes...so just i need some model test papers and pattern ..pls help me friends...

0 Answers  

---

We are using Rosemount 5400 series Radar Level Transmitters in all types of Sump Applications having oily water hdrocarbon petrochemical nature. What we are facing the problem frequently is that always getting reading frezzed at some value. If we do power recycling , sometimes it is working . then making same freezing problem. If anybody faced before such type of problem and also having solution , Please give the answer.

0 Answers   Sabic,

---

what is PM/CM/RCM?

2 Answers   Emco,

---