Table of Contents
Advertisement
Manual
MS-00809-0100-0470
8.1.30
Ethane RT Drift
The retention time for the ethane peak has drifted too close to the end of the analysis
cycle.
Potential cause
This is typically due to contamination in the valves.
Recommended action
Exchange and overhaul the module.
8.2
GC won't power up
Recommended actions
8.3
Un-normalized total error
An un-normalized total error, which typically occurs when the un-normalized total is
outside of ±2 percent of 100 percent, indicates that the amount of stream gas analyzed
is significantly different from the amount of calibration gas analyzed during the last
calibration run.
Recommended actions
Rosemount 470XA
1. Measure the voltage at the power terminal on the back plane.
2. Ensure that the GC is receiving 24 V at the terminal.
3. Ensure that the terminal is wired correctly.
4. Ensure that the terminal is seated correctly in its receptacle.
The terminal should not jiggle or otherwise move when pressed with a finger.
5. Check the lights on the CPU board, local operator interface (LOI), and the light
emitting diode (LED) beside the power terminal.
•
If the CPU board's green lights are on, but the LOI screen is off, replace the
LOI.
•
If the white LED beside the power terminal is on, the GC's fuse is blown.
Replace the fuse.
6. If none of the above actions worked, contact your local Rosemount service
representative.
1. Use MON2020 to generate an analysis report for the analysis cycle that had the
un-normalized total error.
•
If there has been a significant change in atmospheric pressure since the
last calibration, run a normal calibration by selecting Calibration from the
Control menu.
NOTICE
The sample is equalized to atmospheric pressure at the beginning of each
analysis cycle, so that the amount of sample analyzed will change with the
atmospheric pressure. Large swings in atmospheric pressure associated
with weather events can cause changes in un-normalized total outside of the
typical ±2 percent limits.
Troubleshooting
June 2023
127
Advertisement
Table of Contents
