GENEQ > Meteorology > Radiometers

UV-A Radiometer
Model UV-S-A-T

The sensor to measure atmospheric UV-A with thermoelectric temperature stabilization
UV-S Series
The UVS Radiometers form a unique set of instruments for accurate measurements of solar ultraviolet radiation in the atmosphere. The UV Radiometers have sealed, weather resistant cases made from protected aluminium. They permit continuous outdoor operation. The Radiometers can easily be adjusted in the horizontal by help of three leveling screws and the built-in circular bubble level.
The UV Radiometers are available either with thermoelectric temperature stabilization (suffix T) or with an integral electronic temperature compensation (suffix C).
While the temperature stabilization provides highest accuracy, the temperature compensation may be required when the available power is limited. In both cases, a single DC supply voltage is needed for operation.
Features
  • Spectral sensitivities precisely adapted to the measurement task
  • Very good cosine response: ±2.5 % between 0 º and 70 º zenith angle
  • Excellent long-term stability
  • Internal thermostatting at 25 ºC
Description

The UV-S-A-T has a broad spectral response optimised for precise measurements of atmospheric UV-A irradiance.

Compared to the UV-S-A-C, the high accuracy UV-S-A-T is thermostated (heated / cooled at 25 ºC) including filters,detector and pre-amplifier. This provides more accuracy than the temperature compensated UV-S-A sensor. Due to the heating/cooling element it requires more external power.

The UV-S-A-T has a sealed, weather resistant case made from protected aluminium. The sensor permits continuous outdoor operation. The UV-S-A-T can easily be adjusted in the horizontal by help of three leveling screws and the built-in circular bubble level.

Specification
Spectral Response UV-A (315 to 400 nm)
Sensitivity (nominal) of 1 V output corresponds to 75 W/m2 UV-A
Temperature depedence Not Applicable
Response Time (99%) 0.5 s
Non-stability (% change / year) max 3 %
Non-linearity (over full measurement range) ±0.05 %
Contribution at wavelengths >400 nm <0.1 % of output
Expected accuracy for daily sums max 5 %
Cosine response error ±2.5 % (between 0º and 70º zenith angle)