Analytical Industries GPR-1100 ATEX Portable Trace PPM Oxygen Analyzer - Manual (Page 30)

30
Symptom Possible Cause Recommended Action
Erratic O
2
reading
or
Negative O
2
reading
or
No O
2
reading
possibly
accompanied by
electrolyte
leakage
Pressurizing the sensor by
flowing gas to the sensor with:
the vent restricted or
SHUT OFF valve closed
and
suddenly removing the
restriction draws a vacuum on
the sensor
or
partially opening the valves
upstream of the analyzer when
using a pump downstream of
the analyzer to draw sample
from a process at atmospheric
pressure or a slight vacuum
A pressurized sensor may not
leak but still produce negative
readings.
Placing a vacuum on the sensor
in excess 4” of water column is
strongly discouraged. The front
sensing membrane is .000625
thick, heat sealed to the sensor
body and subject to tearing
when vacuum is suddenly
applied.
A premature adjustment of the
ZERO OFFSET potentiometer is
a common problem
Zero the analyzer. If not successful replace
the sensor
Avoid drawing a vacuum on the sensor
From MAIN MENU select DEFAULT ZERO