Why we use 250 ohm resistor in series with HART protocol
communication?

Answer Posted / ahmet

If it had'nt been resistor, 24v had been connection in
parallel to HART device. And a constant current. then there
had not been communication.
That is for isolated 24v and HART com.
for communication with trnsmitter and HART.

Is This Answer Correct ?    2 Yes 5 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

what are the documents(Construction point of view for a process plant) submitted by contactor initially entering in to new site for client?

1765


what is KV and XV valve

1298


we are using centum vp as monitoring with Dell precision work station T3600 but some times PC(s) are restarted automatically . how we can solve this problem? thanks

1772


protection relay watchdog contact operation?

1574


Hi, I am Newely Joined in Construction company instrument engineer? Any one can Plz tell me How can I advanced preparation for Releated Engineering and construction Documents?

2160






Explain the mechanism behind the turbine meter.

696


What is the use of temprature compensation?

716


Im having problems with interfase betwen SPI v7.0 and SPPID v5.05. Previous versions of Intools shoul be fixed with SPPIDproj.ocx file. It was necessary to replace this file with one that allows the connection between different versions of SPPID. It is necessary in the current version to do the same?Thanks

1869


Which topics are covered in Process Control?

1649


Q1: Consider part of a control loop, which excludes the transmitter, consisting of a process, a controller and a control valve which may be represented by two dead times of 0.5 min each and three exponential lags of 0.8 min., 1.0 min. and 1.5 min. respectively. We wish to express this system as an overall first order plus dead time (FOPLD) model ie gain, time constant and process dead time. (We will see later that this is often done, to simplify controller tuning). For this exercise, gain is considered to be 1.0. (A) If the transmitter is a flow transmitter whose behaviour can be described by a dead time of 0.2 min. and an exponential lag of 0.5 min. in terms of the overall dead time and overall first order lag how can the system behaviour be approximated ? Overall dead time = Overall time constant = (B) If the transmitter is a temperature transmitter with a temperature sensor in a protecting well whose behaviour can be described by a dead time of 0.7 min. and an exponential lag of 15 min. how can the overall system behaviour be approximated now? Overall dead time = Overall time constant =

1457


how do we commission inergen system?

1438


What is Droop? What is Step/Gradient Limiter in Turbine Governor control?

2931


what does it mean an active front end in vfd plz explain it briefly

1414


how u calibrate pneumatic n motorized c/v?

1539


Describe the typical instrumentation used in monitoring the performance of a shell and tube heat exchanger.

1549