Calibration At 20.7 - Thermo Scientific 3110 Operating And Maintenance Manual

Calibrating the O
System (continued)
O

Calibration at 20.7%

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Thermo Scientific
There are two methods available to calibrate the O
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• The preferred method calibrates the system to the known ambient O
value of 20.7% and checks the life of the sensor. This method should
be used whenever a new O
• The second method available allows the system to be calibrated to an
independent reference instrument by entering an offset. This method
should be used whenever higher accuracy is required as it takes into
account the effects of the desired chamber temperature setpoint on the
O sensor fuel cell output; however, this method does not measure its
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remaining life.
1. Press the Mode key until the CAL indicator lights.
2. Press the right arrow until the display reads O2 CAL@20.7%.
3. Press Enter.
4. OPEN DOOR appears on the display. Open the outer and inner
doors.
5. The display reads CALIBRATING.
6. When calibration is complete, approximately 2 minutes, an audible
tone sounds and the display returns to O2 CAL@20.7%.
7. The O display will change to 20.7.
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8. Press the Mode key to return to Run.
A new O span value is stored in memory for use as the 20.7% O2
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reference point. The keypad/control panel is "locked-up" during
calibration.
system.
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sensor fuel cell is installed.
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Water Jacketed CO
Section 2
Calibration
2
Incubator 2-5
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