PerkinElmer Photovac 2020, Руководство пользователя

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Detailed Operation
69
General Information
2020 must be calibrated in order to display concentration in ppm or
mg/m³ units equivalent to the calibration gas. First, a supply of zero
air whic h contains no ionizable gases or vapors, is used to set 2020’s
zero point. Then, calibration gas, containing a known concentration
of a photoionizable gas or vapor, is used to set the sensitivity.
Occasionally clean ambient air will be suitable as zero air. Due to
2020’s sensitivity, outdoor air is usually unsuitable for calibration. For
best results, use a commercial source of zero grade air and a second
regulator. Zero air should have not more than 0.1 ppm total
hydrocarbons (THC).
If compound threshold limit values (TLVs) are exceeded, you should
use a gas bag for sampling and calibration.
To determine the TLV of the compounds contained in the calibration
gas, refer to the Material Safety Data Sheet (MSDS) supplied with
your calibration gas cylinder.
If you will be using a gas bag for calibration, you should obtain the
calibration kit (Part No. MX390033). The calibration kit contains a
regulator, a gas sampling bag and a gas bag adapter. See
Calibration Using a Gas Bag on page 73 for details.
NOTE: Disconnect 2020 from the AC adapter before beginning
calibration.