transmitter in 3 connection +,-,And test mode so how Use To Test Mode

Answer Posted / carl_ellis

The 'test' connections on a 2 wire, loop powered pressure transmitter have a diode behind them.

If a milliampmeter is connected across the test terminals (in parallel with the diode), the impedance of the meter is less than the diode's, so current will flow through the milliampmeter. There is not enough voltage drop to forward bias the diode and the diode will not conduct with a low impedance meter circuit connected across it. The diode turns off and the current flows through the meter.

Test terminals are provided for loop troubleshooting so that loop current can be measured without breaking or opening the loop circuit so that the milliampmeter can be put in series in the loop circuit.

Carl Ellis
Measure First

Is This Answer Correct ?    13 Yes 0 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

what is the process to make control schematic ?

1729


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

3279


What are different types of valves?

682


What are the interlocks we have to check during the start up of LP/HP compressor?

1485


what is output of FOUNDATION FIELD BUS transmitter

1694






the whole paper was based on Transducers..questions like define repeatability, error,accuracy,precision..den there were many q. on the conversion of Pa to mmHg and other units.. also..der wer few Q. on some level sensors(with diagram)

1540


what is the procedure of O2 sensor(ABB) calibration?

1710


Why the ammonia and Nitric Acid level indicators is with millimeter ? and What is the conversion form millimeters that level indicator indicate to weight ?

1211


i am preparing for BARC ,so plz mail me how to prepare for BARC. ALSO IF POSIBLE SOME RELATED QUESTIONS. MY MAIL ID IS khushi_4uall2003@yahoo.co.in

2552


Explain about the leakage class of the control valves

1594


Where are oxygen analysers installed in cfbc boilers? What are their usual readings?

1123


Explain bernoulli’s theorem.

614


where uses EXe /EXd/Exo/Exn/Exp/Exq/EXia

9325


Punj lloyd is coming in our Jadavpur Universtiy campus for campus placement. Please send me some hints about the writtend exam. My email id is subratafriends@gmail.com

2373


䑰ҕ䔈ҕ䖠ҕ䘰ҕ䛀ҕ䝐ҕ䟐ҕ䢐ҕ䥐ҕŹ

1533