Ecotech HiVol 3000

Calibration HiVol 3000 User Manual 1.7
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Figure 19 Calibration Set-up
4.1.1 Flow rate calibration – Temperature and Pressure
Corrections
Calibration of flow rate with an Orifice Plate requires consideration to be
given to current ambient temperature and barometric pressure conditions. A
certified thermometer and digital barometric pressure indicator are
recommended to obtain this data at the site where the calibration is to be
performed.
Alternatively, the current ambient air temperature and pressure may be
obtained from a local weather bureau. The average barometric pressure can be
estimated from the altitude of the site either from altitude-pressure tables or by
reducing the sea level pressure by 1.18kPa for each 100 metres of altitude
(valid up to ~1000m.)
Ideally, the ambient conditions during calibration should reflect the average
ambient conditions during a typical sampling period. This will minimise
errors due to drift in the electronics. If possible, choose a time of day when the
temperature and barometric pressure are reasonably stable.
Note: Calibration of the HiVol 3000 is independent
of the reference (STP) conditions, which are used
only to calculate the corrected sample volume.
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