Other Problems With The Instrument - Teledyne MX300-I Operating/Service Instructions Manual

Portable Oxygen Monitor
50
6 (5)
(There is no
indication of
which key is
stuck)
7(2)
(There is no
indication of
the type of
DAC failure)

3.10 Other Problems with the Instrument

Most other problems arise from either mechanical damage from the
instrument falling from a bench or table, or electronic component
failure. In these units, repair or troubleshooting the PCB or individual
component on the board is not feasible. It requires specialized test
equipment and probes not generally available to the public. Under most
circumstances a replacement of the entire PC Board is recommended.
The instrument must be returned to the factory for PCB installation.
Occasionally, depending on the environment of use, keys can
become stuck or function erratically due to contamination. Use a mild
Teledyne Analytical Instruments
5 The ADC circuit failed during POST.
6 A stuck key has been detected. The second digit
example (5) on the display shows which key is
stuck:
0 - Low Alarm
1 - Batt
2 - Cal
3 - Up
4 - Down
5 - Silence
6 - High Alarm
7 - Alarm Test
8 - Key Lock
7 A failure has occurred during the automatic
calibration of the digital to analog converter (DAC)
circuit. The second digit example (2) shows the
type of digital to analog failure.
0 - Measurement
1 - High Test
2 - Low Test
3 - Offset Cal
4 - Gain Cal
Service Manual
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