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z
To improve the calibration accuracy, perform the calibration under actual sampling
conditions if possible.
Calibration Methods
Flow Rate Calibration Method
Calibration is recommended to further improve the accuracy of sampling.
An optionally available standard flow meter can be attached to the sampler's intake side.
Calibration at the work site is simplified by using Sibata OF-1S orifice flow meter (sold
separately) as the standard flow meter (Rectangular adapter for orifice flow meter is required.
A commercially available USB cable is required for automatic calibration).
For calibration method by using OFD-1, refer to the OFD-1 operation manual.
(The Orifice flow meter OF-1S (Discontinued) is also usable as a standard flow meter.)
The following is manually calibration method by a using standard flow meter such us OFD-1 or
OF-1S.
1. In the calibration mode, set the flow rate span value to 1.000, and return the zero value to
0.000.
2. Return to the main screen, and set the flow rate you wish to calibrate.
3. Press the [START/STOP] button, and start the high volume air sampler.
4. Record the standard flow meter value and the sampler's instantaneous flow rate display.
5. Calculate the span value. (See page 40.)
6. If you are performing a 2 point calibration, set the other flow rate, and proceed from step 3.
7. Switch to the calibration mode, and enter the obtained span value and zero value.
If you are only adjusting the accuracy of a particular flow rate, perform an one point calibration.
If you are using the product at multiple flow rate values, perform either the 1 point calibration
before every sampling or the 2 point calibration.
For the 1 point calibration, only change the span value. For the 2 point calibration, change both
the span value and zero value.
Atmospheric Temperature Calibration Method
Calibration can similarly be performed with respect to the atmospheric temperature sensor. Use a
standard thermometer, and place it near the atmospheric temperature sensor.
1. In calibration mode, set the atmospheric temperature span value to 1.000, and return the
zero value to 0.000.
2. Set the mode display to atmospheric temperature display. (See page 28.)
3. Record the standard thermometer value and the equipment's atmospheric temperature
display.
4. Calculate the zero value. (See page 40.)
5. If you are performing the 2 point calibration, establish a different temperature environment,
and proceed from step 2.
6. Switch to calibration mode, and enter the obtained span value and zero value.
For the 1 point atmospheric temperature calibration, only change the zero value. If you change
the span value, this will adversely affect the accuracy.
For the 2 point calibration, change both the zero value and span value.
The temperature sensor region is not waterproof, so never perform atmospheric temperature
calibration when it is wet.
