Vaisala K-PATENTS PR-43, User Manual

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10. Instrument verification
Th following sections describe the process and steps for refractometer verification, and the
corrective actions necessary.
10.1 Refractometer verification
The verification of the PR-43 calibration is made using a set of standard refractive index
liquids. In order to perform a valid verification, at least three liquids need to be used. The
verification is valid only within the refractive index range defined by these three liquids.
The instrument recognizes automatically the following refractive index standard liquids (the
values are stated at +25 °C):
• 1.3200
• 1.3300
• 1.3400
• 1.3500
• 1.3600
• 1.3700
• 1.3800
• 1.3900
• 1.4000
• 1.4100
• 1.4200
• 1.4300
• 1.4400
• 1.4500
• 1.4600
• 1.4700
• 1.4800
• 1.4900
• 1.5000
• 1.5100
• 1.5200
The accuracy of the certified standard refractive index liquids is ±0.0002 and they can
betraced back to NIST standards # 1823 and # 1823 II. As the specified accuracy of the PR-43is
±0.0002, then the representative level is the sum of the two accuracy specifications, that is
±0.0004.
Vaisala provides a set of standard R.I. liquids, PR-2300, containing five selected liquids (1.3300,
1.3700, 1.4200, 1.4700, 1.5200). The set can be ordered from Vaisala. Other liquids are available
on request.
PR-43 Series User Guide M212455EN-B
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