Fisher FIELDVUE DVC6200 Instruction Manual page 86

DVC6200 Digital Valve Controller
Symptom
1. Analog input reading at
instrument does not match
actual current provided.
2. Instrument will not
communicate.
7
3. Instrument will not
calibrate, has sluggish
performance or oscillates.
78
Table 7-3. Instrument Troubleshooting
Possible Cause
1a. Control mode not Analog.
1b. Low control system compliance voltage.
1c. Instrument shutdown due to self test failure.
1d. Analog input sensor not calibrated.
1e. Current leakage.
2a. Insufficient Voltage Available.
2b. Controller output Impedance too low.
2c. Cable capacitance too high.
2d. HART filter improperly adjusted.
2e. Improper field wiring.
2f. Controller output providing less than 4 mA to loop.
2g. Disconnected loop wiring cable at PWB.
2h. PWB DIP switch not set properly.
2j. PWB failure.
2k. Polling address incorrect.
2l. Defective terminal box.
2m. Defective Field Communicator or ValveLink
modem cable.
2n. ValveLink modem defective or not compatible
with PC.
2p. ValveLink hardlock defective or not programmed.
3a. Configuration errors.
3b. Restricted pneumatic passages in I/P converter.
3c. O-ring(s) between I/P converter ass'y missing or hard
and flattened losing seal.
Action
1a. Check the control mode using the Field Communicator. If
in the Digital or Test mode, the instrument receives its set
point as a digital signal. Control is not based on input current.
Change Control Mode to Analog.
1b. Check system compliance voltage (see Wiring Practices
in the Installation section.
1c. Check instrument status using the Field Communicator
(see Viewing Instrument Status in the Viewing Device
Information section).
1d. Calibrate the analog input sensor (see Analog Input
Calibration in the Calibration section).
1e. Excessive moisture in the terminal box can cause current
leakage. Typically the current will vary randomly if this is the
case. Allow the inside of the terminal box to dry, then retest.
2a. Calculate Voltage Available (see Wiring Practices in the
Installation section). Voltage Available should be greater than
or equal to 11 VDC.
2b. Install a HART filter after reviewing Control System
Compliance Voltage requirements (see Wiring Practices in the
Installation section).
2c. Review maximum cable capacitance limits (see Wiring
Practices in the Installation section).
2d. Check filter adjustment (see the appropriate HART filter
instruction manual).
2e. Check polarity of wiring and integrity of connections. Make
sure cable shield is grounded only at the control system.
2f. Check control system minimum output setting, which
should not be less than 3.8 mA.
2g. Verify connectors are plugged in correctly.
2h. Check for incorrect setting or broken DIP switch on the
back of the PWB. Reset switch or replace PWB, if switch is
broken. See table 7-2 for switch setting information
2j. Use a 4−20 mA current source to apply power to the
instrument. Terminal voltage across the LOOP+ and LOOP−
terminals should be 9 to 10.5 VDC. If the terminal voltage is
not 9 to 10.5 VDC, replace the PWB.
2k. Use the Field Communicator to set the polling address
(refer to the Detailed Setup section). From the Utilities menu,
select Configure Communicator and Polling. Select Always
Poll. Set the instrument polling address to 0.
2l. Check continuity from each screw terminal to the
corresponding PWB connector pin. If necessary, replace the
terminal box assembly.
2m. If necessary, repair or replace cable.
2n. Replace ValveLink modem.
2p. Replace if defective or return to factory for programming.
3h. Verify configuration:
If necessary, set protection to None.
If Out of Service, place In Service.
Check:
Travel Sensor Motion
Tuning set
Zero control signal
Feedback Connection
Control mode (should be Analog)
Restart control mode (should be Analog)
3j. Check screen in I/P converter supply port of the module
base. Replace if necessary. If passages in I/P converter
restricted, replace I/P converter.
3k. Replace O-ring(s).
September 2010