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partially or wholly, for any purpose inconsistent with which it was produced. This information may not be reproduced or disclosed without prior
express consent.
Troubleshooting
The MX300-I oxygen monitor provides a variety of built-in safety features that prevents its use
when a fault is detected. When a unit displays the message -
√
SENSOR and sounds the audible
and visual alarm continuously, it is an indication of a faulty connection between the sensor and the
unit or an expired or faulty sensor. To determine where the difficulty lies, refer to the following
guidelines in Table 1.
Table 1 Troubleshooting
Symptom
Why
What To Do
New sensor responds
slow or drifts.
If the sensor is new
and was just removed
from its sealed bag it
may need to run for
several hours.
A) Wait 1-2 hours and
recalibrate.
A) Recalibrate using dry gas
making sure the reading
stabilizes before making any
adjustments.
B) Make sure that at least 6" (30
cm.) of tubing is attached to the
exhaust side of the tee adapter
to prevent back filling. 02 flow
rate should not exceed 5 I/min.
C) Oxygen concentration at the
sensor is significantly higher
than 21%. Take the instrument
to a well-ventilated area and
check the reading again.
Sensor will not read
below 22 % after
calibration in 100% 02.
Calibration in 100%
was invalid or the room
air is contaminated with
excess oxygen.
D) Try calibrating with a known
good sensor; if this fails, see
symptom "Reading drifts over 2-
3%..."
