UVP UVX, Instruction Manual

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UVX Radiometer 19
Figure 10: Typical Sensor Response Versus Incidence Angle
Calibration Traceability
For direct traceability to NIST standards, UVX sensors must be returned to the UVP calibrations
laboratory for calibration once every 6 months. UVP does not stand behind calibrations performed by
unauthorized companies.
UVX Series Sensors are calibrated by adjusting their response to match that of an UVP Transfer
Standard Detector when exposed to radiant incidence of the appropriate calibration wavelength from a
stable, effectively monochromatic source.
The calibration of UVP Transfer Standard Detectors is accomplished by measuring their response to a
stable, effectively monochromatic radiant source of the appropriate wavelength. The absolute radiant
incidence level from this source is set by simultaneously matching it with that of National Institute of
Standards and Technology (NIST) standard of spectral irradiance. This calibration is performed at UVP
calibrations laboratory a minimum of once every six months.
The NIST standard of spectral irradiance used by UVP is a 1000 watt tungsten lamp. This lamp is
replaced after every 20 hours of operation.
Period of Calibration
UVP recommends recalibration of the UVX Series Sensors every 6 months, especially when used by the
governmental agencies and in other areas of critical application.
NOTE:
All sensors must be calibrated by the UVP calibrations laboratory for direct traceability to NIST
standards.
In non-critical applications, the user may choose a longer period of time between calibrations. However,
the actual time that a sensor will remain within tolerance is dependent on such factors as care in handling