A DVC 6030 is wired according to schematic with 250 ohm resistance, it communicates with 475 HART communicator but when I try to save the configuration to Internal Flash the HART application aborts and return to main screen.Moreover, the output of positioner is not responding to input current. It gives maximum pressure(60 psi) to the actuator no matter how much input current is provided, this has created problem in calibration as well.Need help to diagnose the problem(s)
Hi Aleem,
The DVC6030 is an AO type of device which means that a 250 ohm resistor is not used in the wiring. This can disrupt communications to the instrument..
1) The instrument may be out of service meaning that it won't respond to any changes in the input signal. This feature is in place so that nobody remotely change valve position while a technition is physically working on it. By putting the instrument back in service - it will respond.
2) There may be a physical issue with the instrument - possibly elastomers that have hardened and failed causing internal leakage driving instrument to respond this way.
3) It's also possible that the communications to the instrument are being interfered with due to the extra resistance in the loop (250 ohm resistor).
My suggestions:
1) Remove the resitor and try the excersize again, see iif this resolves the issue.
2) If the isses aren't resolved - contact your local Emerson representative and discuss with them for resolution. If you don't know who they are, follow this link and it will provide the contact info for you: www2.emersonprocess.com/.../contacts.aspx
Lorin Miller
In reply to LorinMiller:
Hi LorinMiller,
Thanks for your prompt response but as I read the manual for 475 communicator it was suggested to use 250 ohm resistor in loop for it to communicate
and thats true because without it communicator prompts for "No Device Connected" in online mode. Moreover, The communicator reads correctly the Analog Input (4 - 20 mA) but the positioner doesnot change output to whatever the input is.
2. I will have to check on the elastomers.
3. The instrument was checked at "In Service" and "Out of Service" modes but no change in behavior. It does not respond to Auto Calibration as well
4. I did all of this experiment at a spare DVC6030 and it all went well, it communicated, it saved configuration, it was calibrated( Auto and Manual Both).
In reply to Riyaz Ali:
Hi Riyaz,
I am pretty sure It is not DVC6030 SIS and we are providing 4-20 mA as Analog Input. Moreover, The DIP switch is in Point - Point Loop mode in the PWB assembly.
It would be helpful if you guide me to any other way of checking if its in multidrop mode.Regards
Aleem Ullah
Instrument Engineer, Agritech Ltd.
Iskanderabad, Mianwali, Pakistan
+92 331 4014840
It would be helpful if you guide me to any other way of checking if its in multidrop mode. Regards
Since you mentioned the issue was resolved with a spare DVC6030, it appears that you might have a unit that needs further investigation and the issue is not related to the host, hook-ups or installation. Our Emerson Paskistan local business partner's contact info is given below. If the unit is still within the warranty period, we can have the unit repair/replaced through Technobiz.
Technobiz ( Private) Limited
213-A, 2nd Floor, Continental Trade Centre
G/6, Scheme-5, Block - 8,Main Clifton Road,
Karachi, Pakistan
Tel: +92 21 35302961-62
Contact: tariq.ashfaq@technobizz.com
Regards,
SP Goh