what do you mean by Loop checking ? What are the cold loop
check and hot loop check? what are the difference between
these two loops?

Answer Posted / carl_ellis

Answer:
A Cold Loop check is cold because it is done without
powering the loop.

A cold check consists of checking wire continuity from the
field instrument through junction boxes and through DCS/PLC
marshalling panel terminals to the control panel. Once
continuity has been confirmed, then a Hot Loop Check is
performed on the Loop's I/O.

A Hot loop check is 'hot' because it is done with the loop
powered up.
A Hot loop check consists of
- simulating a process input at the field instrument and
then checking the instrument's output and the response to
the process signal input at DCS/PLC.
- simulating outputs at the control end and checking for
correct response at the field end.

Carl Ellis
Measure First

Is This Answer Correct ?    5 Yes 1 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

What is the purpose of LO Overhead tank in turbines.

1575


In turbine what does term CDP, NI, NH, HSSOC means.

2042


Which type of diaphragm use in costic line, dm water line, natural gas line, oil line?

705


Why mixer nd grinder Is example of constant torque load not variable torque load ???

1494


applications of plc in printing and packaging?

1678






what is scale factor of proximitor & unit of the vibration.

1684


what is exact time to study dcs and plc cources

1562


what is use of communication wire in multipare cable(oil and gas field), why this communication wire not used in single pair cable?

1672


draw the block diagram of a level transmitter ?

1933


Hi i am aneesh, done btech in applied electronics & instrumentatiin. And then i took mba in finance & marketing.After that i got placement in finance co and worked there for 3.5 yrs.Now i wanted to come back to engineering job.But without engg experience, i may not able to find an opening.i have done a course related to flow meters and ite calibrations. Kindly suggest where should i try to get a job?

1535


Give 2 application of quartz crystal used for process parameter measurement.

1580


Explain the key components of control loop?

572


3. Differentiate between ultrasonic flowmeter and radar type flow meter.

2441


DEAR SIR/MADAM MY NAME IS ARKAPROVA BHATTACHARYYA.I AM A FRESHER INSTRUMENTATION ENGINEER.CAN YOU PLEASE SEND SOME QUESTION PAPERS OF GRADUATE ENGINEER TRAINEE EXAM OF DVC(DAMODAR VALLY CORPORATION).MY EMAIL IDs ARE arka_aec@rediffmail.com.

1458


How to calibrate an pressure gauge with yantrika test bench?

2374