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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.
Appendix F: Portable Oxygen Monitor
General Service Information
The Teledyne Model MX300-I Portable Oxygen Monitor is designed to be robust yet compact in
size. In order to achieve maximum reliability in a microprocessor-based instrument, a single PC
board is used which relies exclusively on surface mount technology. Without access to specialized
probes and test equipment, troubleshooting and repair of circuit board components are not
feasible. A factory replacement of the entire PC board is more cost effective than a field repair of
an individual component.
With the exception of replacing the sensor or batteries there are no user-serviceable components
inside the unit. There are no potentiometers or other adjustments to be made within this instrument.
If a problem arises with either of these models that cannot be corrected by recalibration ,changing
the batteries or replacing the sensor as described in the users manuals, the unit must be sent back
to the factory for repair or replacement. See Return Authorization for Service for instructions on
obtaining a Return Merchandise Authorization (RMA) number before sending a unit back to
Teledyne for repair.
Overall Maintenance
The MX300-I requires very little maintenance, other than calibration, checking and changing the
batteries and sensor, and cleaning the plastic housing. Occasional cleaning of the plastic surface
can be done with isopropyl alcohol. Should any part of the instrument malfunction or fail to perform,
the unit should be removed from service. There are no user-serviceable components within the
instrument.
Battery Maintenance
DO:
Test batteries regularly. (Replace immediately when all 5 bars are missing).
DO:
Always use alkaline batteries.
DO:
Recalibrate after replacing batteries.
The MX300-I instrument incorporates a battery test feature that provides the approximate amount
of useful life remaining on the set of batteries. Excessive alarm activation will wear down the
battery faster than usual.
The minimum detectable change in battery voltage corresponds to an increment of about 50 hours,
meaning that the battery voltage reading may not change for several hours at a time.
If the monitor is not used for a period of 30 days or more, the batteries should be removed prior to
storage.
