ABB XSeriesG4 User Manual page 97

–
AD converter is over or under range (DP, SP or Tf)
–
Loose wiring connections
–
Faulty RTD probe
If A to D converter readings are within range, AD is shaded.
Step-by-step instructions
Begin by collecting data from the unit.
View the event log in PCCU for codes (see PCCU Help Files for more information):
– 99 AD converter could not be read
– 100 AD converter could be read again.
If an event code is found, follow the guidelines for returning the transducer to Totalflow for repair or replacement. If an
event code is not found, continue to the next step.
In the PCCU Entry screen, monitor the readings by clicking I/O Subsystem, On-board and Analog Inputs. Check SP,
DP and temperature to determine which measurement channel is causing the alarm.
– If the alarm is caused by the SP or DP channel, equalize and vent the manifold.
- If the alarm disappears: SP or DP cell is not ranged properly or
the manifold may have a blockage.
- If the alarm is still present, replace the transducer.
– If alarm is caused by the temperature channel, skip to Step 9. Otherwise, go to the next step.
Set the XMV back to Factory calibration. If this corrects the alarm, recalibrate the XMV to the correct field calibration. If
the alarm is not corrected, continue to the next step.
Perform a WARM start on the unit. Verify that unit is not displaying a LL (Low Lithium) alarm, then remove power from the
unit. Restore power to the unit. If the AD Failure alarm is not corrected, continue to the next step.
Perform the Save and Restore function. Follow the procedure in section 4.2.1, Using the Save and Restore utility. Be
sure to restore these files to the tfCold Drive.
Perform a COLD start on the unit following reset procedures covered in this section. If the problem is not corrected,
continue to the next step.
Check RTD wiring at XMV.
Perform the following three procedures found next in this section:
– RTD continuity test (section 5.2.6)
– RTD current source resistive test (section 5.2.7)
– RTD impedance test (section 5.2.8)
Contact Totalflow to repair or replace the XMV.
RTD continuity test
Should the readings from the RTD be suspect, follow the instructions below to test the RTD probe.
Required equipment
–
Digital MultiMeter (DMM) with alligator clip leads
Step-by-step instructions
Begin by disconnecting power and communications from the XMV.
Disconnect the RTD from the XMV.
Perform continuity test on wires leading to the probe. Set DMM to 200 Ohm or Continuity Audio.
Check continuity of the first wire pair (typically red or black) by connecting one lead to each wire. The meter should read
zero or close to zero.
XSeriesG4 Remote Controller User's manual 2103334 Rev. AB | 85
5 Troubleshooting