Nellcor OXIMAX N-600X Series Service Manual page 116

Modifying and Testing the Oximeter
LED Excitation Test
The LED Excitation Test utilizes normal system components to test circuit operation.
Use a OxiMax™ Max-A pulse oximetry sensor to examine LED intensity control. The
test uses the red sensor LED to verify intensity modulation controlled by the LED
intensity control circuit.
To test the circuit operation:
1. Connect the oximeter to an AC power source.
2. Connect a DOC-10 pulse oximetry cable to the oximeter SpO
3. Connect a Max-A pulse oximetry sensor to the OxiMax sensor input cable.
4. Press the ON/STANDBY button to turn the oximeter on.
5. Leave the Max-A pulse oximetry sensor open with the LEDs and photo detector
visible.
6. After the oximeter completes a normal power-on sequence, verify the Max-A
pulse oximetry sensor LED is brightly lit.
7. Slowly move the Max-A optical sensor LED in proximity to the photo detector
element of the Max-A pulse oximetry sensor on the opposing side of the clip,
closing the sensor slowly.
8. Verify the LED intensity decreases as the LED approaches the optical sensor.
9. Open the Max-A pulse oximetry sensor and notice the LED intensity increases.
10. Repeat step 8 and the intensity continues to decrease. This variation is an
indication the microprocessor is in proper control of LED intensity.
11. Press the ON/STANDBY button to turn off the oximeter.
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Figure 81. SpO Sensor Port
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10030881 Rev. B 12-2008
Sensor Port.
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Service Manual