Why the industry's standard current standards are from 4mA to
20mA,not from 0mA or any other range?

Answer Posted / fidelis

This is for the purpose of identifying a fault either in
the instrument or in the control loop. If there is a fault
in an instrument, the reading on that instrument will be
zero as when the transmitter is not reading any data due to
maybe a broken loop, so one may not be able to tell what
the problem is. But with the 4-20mA standard, it will be
simple to tell if the transmiter is faulty or not. This
makes trouble-shooting easy.

Is This Answer Correct ?    28 Yes 0 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

How can a d.p. Transmitter be calibrated?

684


what effects a surging can produce in the compressor

1470


Please tell me details about Sox,Nox,SWAS analyser????

3280


What is profibus?

646


what is a vortex flow meter,mass flow meter and electromagnetic flow meter.particular use of this.means in which condition particular meter is used.

1728






Explain types of valves?

666


why we are using magnet for calibration of gas detector?

1809


If a warning lamp will operate with the ground circuit is bypassed with a jumper wire to ground, what should you check?

1623


pls give me presant awerness quistion and answer in my emailid.

2317


how radio frequency level probes works with its controller ? what is its principle ? pls give me brief explanation?

1398


What is wet leg condition and why is it used?

1552


WHAT IS MEANT BY PROJECT MANAGEMENT STRATEGIES IN INSTRUMENTATION?

3034


how many maximum enter 2mm Dia solid cylindrical pipe into 8mm Dia hollow cylindrical pipe. give answer with calculation.

1576


Displace type LT to be calibrated in workshop, wt. 40, dia- 60 mm, density- 0.8kg/cm3.

1437


how pressure transmitter work, what is its principal to measure and how its generate signal. for pressure transmitterinstallation which precautions must be taken ??

1319