Interested to Buy Any Domain ? << Click Here >> for more details...
Why we use 250 ohm resister in series
hart communicator?
- 3 Answers
- 15723 Views
- Thermax, I also Faced
- E-Mail Answers
Answer Posted / carl_ellis
Answer #2 is not correct because the HART communicator is
not an analog input, it does not use a 1-5Vdc signal. A
HART communicator gets and display a transmitter's primary
variable (or other variables) as a digital value; NOT as an
analog value, not as a 1-5Vdc signal developed across an
analog input's resistor. I repeat, HART communications is
NOT analog in nature, it is digital.
The HART Foundation specifies a minimum resistance of 230
ohms, as described in answer #1, in order to develop the
1200 baud HART signal, that rides on top of the DC loop
current signal.
It's easy to prove that 250 ohms (for 1-5Vdc) is not a
requirement for HART communications as a bench test.
Take a 2 wire loop powered HART transmitter, connect a DC
power supply and use a 330 ohm resistor in series in the
loop. The communicator will work and the primary process
variable will be correct. Then try a 470 ohm resistor.
The 470 ohm resistor will work, as well, and the primary
variable will be correct.
| Is This Answer Correct ? | 7 Yes | 1 No |
Post New Answer View All Answers
what is the procedure for auto tune in masoneialn 12300 series displacer type transmitter?
Can combine control system for Emergency control system (ESD)and Fire & Gas System ( F & G) is possble to built and offer to client? Can such system is as per Norms in India?
flow transmeter accuracy 0.075% of full scale & find ucertainty is 0.025 % so what is maximum limit band of uncertainty
what is the difference between Cv and air consumption? why the customer needs Air consumption details?
Which Signal hart communicator work? If there any signal change when hart connect while transmitter in line ?
a flow transmitter [range-0-400mbar] connected in process line. please explain me how to calibrate the flow transmitter , & how to do static error
hi my name is rakesh patel i just complited my be in instrumentation & control now i am going to working as a validation engineer in a poject department so what is a scope in a future as a validation engginer ? what line is good for me can any bady give me complete solution please? your regard rakesh patel
Reason for capillary type dp level transmitter fluctuation
what is commisioning procedure,2)what is is the main work in commisioning in the field tx to dcs, plz send me detail
I want measure the volumetric flow of gas in waste heat recovery Boiler?Tell me how and which type of instruments required. Plz mail me:naba02222@gmail.com Sam please post the answer .
How to calibrate the flow transmitter
Hi Friends i need Electronics&Instrumentation Engg question papers for BARC written test by coming 20th May 2008 pls post ur use full info to kkumarei@gmail.com. Or for suggestions pls give one missed call to 9962122264
plz tell me clearly about PID.."when v have to change I value,D value,GAIN??
What are continuances of connecting earthing and shield of branch cables (instrument to Junction box), at the same earthing pot provided on JB? Is it ok, or may produce some problem?
why orfice is not used for main steam flow calculation
