Nq Ratio Below The Permitted Limit; Nq Ratio Above The Permitted Limit; Ratio Out Of The Limit; Source Fault - Emerson Rosemount 935 Reference Manual

Reference Manual
00809-0100-4035
7.7

NQ Ratio below the permitted limit

Host status = F
0-20 = 1 mA
Light-emitting diode (LED) = yellow, blinking
Table 7-7: Potential cause and resolution
Potential cause
Gas in path
7.8

NQ Ratio above the permitted limit

Host status = F
0-20 = 1 mA
LED = yellow, blinking
Table 7-8: Potential cause and resolution
Potential cause
Poor alignment
7.9

Ratio out of the limit

Host status = F
0-20 = 1 mA
LED = yellow, blinking
Table 7-9: Potential causes and resolutions
Potential cause
Poor alignment
Dirt on the window
Detector fault
7.10

Source fault

Yellow light-emitting diode (LED) blinking at the source
Table 7-10: Potential Causes and Resolutions
Potential cause
Low/high input voltage
Internal fault
Rosemount 935
Resolution
Ensure that the path is clean and the weather
conditions are good.
Resolution
Align.
Resolution
Align.
Clean the window.
Replace or repair the detector.
Resolution
Check the power supply and installation.
Replace the source.
Troubleshooting
May 2022
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