Nellcor N-180, Manual

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Section 7: Performance and Safety Tests
7-7
c. The pulse beep tone is audible.
d. The audio alarm returns in approximately 60 seconds.
2. Press audio alarm off button; rotate control knob clockwise until
OXYGEN SATURATION display reads OFF.
3. Release audio alarm off button.
4. Verify audio alarm off indicator and RED display flash and alarm
does not return.
■
Volume Control
1. Rotate control knob clockwise and verify sound level of beep tone
increases.
2. Rotate control knob counterclockwise and verify beep tone can be
turned off completely.
■
Oximetry Circuit Checks
To perform the oximetry circuit checks you must examine RAM locations
three through six. In all, there are seven
RAM
locations; but, the first
three relate to ROM version numbers not to operational data. To
examine the seven RAM locations:
1. Observe front panel oxygen saturation and pulse rate displays.
2. Simultaneously press and hold HIGH SAT and audio alarm off
push buttons.
3. Turn control knob.
The number shown in the oxygen saturation display identifies one
of seven (zero to six) visible RAM locations. Concurrently, the
number shown in the pulse rate display is the real-time value of
the RAM location shown in the oxygen saturation display.
The zero RAM location stores the first digit of the monitor software
version. This number varies depending on monitor manufacture
date. A typical number is one, meaning version one.
The first location of RAM stores the second digit of the monitor
software version. This number can also vary depending on monitor
manufacture date. A typical number is zero. When appended to the
number in location zero the version is 1.0.
The second RAM location stores the software version of the
oximeter module (MP -203) installed in the monitor. This number
also depends on MP-203 manufacture date. A typical number is
101, meaning version 1.01.
You can examine all seven RAM locations by rotating the control
knob while you continue to press the two buttons.
4. Examine following RAM locations to verify proper monitor
operation.
a. Connect a PT-2500 pulse oximeter tester to monitor sensor
input.