Automatic Calibration, Direct Flow Calibration Barb

medicalManual.RevD.qxd 9/9/04 4:18 PM Page 10

2.1.3 Automatic Calibration

After the unit is turned on it will automatically calibrate to room air. The display should be stable and reading 20.9%.

To check the oxygen concentration of a sample gas: (after the unit has been calibrated)

1.Connect the Tygon tubing to the bottom of the

analyzer by threading the barbed adapter onto the oxygen sensor. (figure 2, B)

2. Attach the other end of the sample hose to

FIGURE 2

the sample gas source and initiate flow of the

sample to the unit at a rate of 1-10 liters per

minute (2 liters per minute is recommended).

3.Using the "ON/OFF" key, make sure the unit

is in the power "ON” mode.

4.Allow the oxygen reading to stabilize. This will normally take about 30 seconds or more.

2.2Calibrating the MAXO2®+ Oxygen Analyzer

NOTE: We recommend use of medical grade oxygen at 100% when calibrating the MAXO2® +.

The MAXO2® + Analyzer should be calibrated upon initial power-up. Thereafter, Maxtec® recommends calibration on a weekly basis. To serve as a reminder, a one week timer is started with each new calibration. At the end of one week a reminder icon “” will appear on the bottom of the LCD. Calibration is recom- mended if the user is unsure when the last calibration procedure was performed, or if the measurement value is in question.

For hospital and home care a new calibration is required when

•The measured O2 percentage in 100% O2 is below 97.0% O2

•The measured O2 percentage in 100% O2 is above 103.0% O2

•The CAL reminder Icon is blinking at the bottom of the LCD

•If you are unsure about the displayed O2 percentage. (see Factors influencing accurate readings.)

For ID testing, (or optimum accuracy) a new calibration is required when

•The measured O2 percentage in 100% O2 is below 99.0% O2

•The measured O2 percentage in 100% O2 is above 101.0% O2

•The CAL reminder Icon is blinking at the bottom of the LCD

•If you are unsure about the displayed O2 percentage. (see Factors influencing accurate readings.)

A simple calibration may be made with the sensor open to static Ambient air. For optimum accuracy Maxtec® recommends that the Sensor be placed in a closed loop circuit where gas flow is moving across the sensor in a controlled manner.

2.2.1 In Line Calibration (Flow Diverter – Tee Adapter)

1.Attach the diverter to the MAXO2®+ by threading it on to the bottom of the sensor.

2.Insert the MAXO2® + in the center position of the tee adapter. (figure 2, A)

3.Attach an open-ended reservoir to the end of the tee adapter. Then start the calibration flow of oxygen at two liters per minute.

Six to 10 inches of corrugated tubing works well as a reservoir. A calibra- tion oxygen flow to the MAXO2® + of two liters per minute is recommended to minimize the possibility of obtaining a "false" calibration value.

4.Allow the oxygen to saturate the sensor. Although a stable value is usually observed within 30 seconds, allow at least two minutes to ensure that the sensor is completely saturated with the calibration gas.

5.If the MAXO2® + is not already turned on, do so now by pressing the analyzer “ON” button.

6.Press the Cal button on the MAXO2® + until you read the word CAL on the analyzer display. This can take approximately 3 seconds. The analyzer will now look for a stable sensor signal and a good reading. When obtained, the analyzer will display the calibration gas on the LCD.

NOTE: Analyzer will read “Cal Err St” if the sample gas has not stablized.

2.2.2 Direct Flow Calibration (Barb)

1.Attach the Barbed Adapter to the MAXO2® + by threading it on to the bottom of the sensor.

2.Connect the Tygon tube to the barbed adapter. (figure 2, B)

3.Attach the other end of the clear sampling tube to a source of oxygen with a known oxygen concentration value. Initiate flow of the calibration gas to the unit. Two liters per minute is recommended.

M A N U FA C T U R E D B Y M A X T E C , I N C .

W W W. M A X T E C I N C . C O M