FAQ

• UV Radiometers

  • Can I measure specific parts of the UV spectrum with the CUV 5?

    • No, it cannot separate UV-A from UV-B, it measures both together, for measurement of these parameters individually we recommend our UVS Series of radiometers.

  • What is the calibration frequency of UV radiometers?

    • We advise to re-calibrate the UV radiometers every two years.

  • Can a METEON data logger be connected to UVS-A-T and UVS-B-T?

    • No, the input range of the METEON is limited to 200 mV (the output from the UVS-X goes up to 3V)

  • What does ‘Mean Adjustment Factor’ mean on the calibration certificate of a UV radiometer?

    • The ‘Mean Adjustment Factor’ on the calibration certificate is equivalent to the sensitivity of a pyranometer. It applies to specific Ozone column and Air-mass (solar elevation) values used as the standard test conditions. Data files are provided to correct the measured values for other Ozone and Air-mass conditions (see Radiation Amplification Factor).

  • Is there an UV-C sensor available?

    • No, we do not have a UV-C sensor. UV-C from the sun is almost completely absorbed by Ozone in the atmosphere and virtually none reaches the ground. 

  • I noticed that the UVS series has a temperature controller, which make it constant 25 ˚C. Do you think this controller can cover ‘automatic temperature compensation’?

    • Actually our thermostat is better than a temperature compensation. We used to have UVS-X-C versions of our instrument (these were temperature compensated). We stopped that line because the UVS-X-T version performed much better. Temperature compensation means correcting the output for changes in sensor temperature. Because our sensor is always the same temperature there is no compensation required. The internal Peltier element heats or cools the actual complete detection system that measures the UV light.

  • What is the bandwidth of the CUV 5 and why does this not match the UV spectrum?

    • The bandwidth of the CUV 4 is 280 - 400nm. The 50 % points are defined to be 290 - 385 nm. 

      

  • What does ‘Radiation Amplification Factor’ mean?

    • The radiation amplification factor is a correction for solar zenith angle and Ozone column. This is required because these two factors strongly influence the UV measurement.

  • Can the UVIATOR software operate with a Campbell logger and its software? Or, do I have to use LOGBOX-SD for compatibility with UVIATOR?

    • The UVIATOR can work with any data logger that is capable of storing UVS measurements. The UV-data must to be stored in the correct format, and Campbell loggers can do this. More details can be found in the UVIATOR manual.

  • Why do I need the UVIATOR software?

    • For easy correction for solar zenith angle and Ozone column.

      This is required because these two factor strongly influence the UV measurement. With the UVIATOR software you can collect the Ozone column data from the OMI satellite data per date, time and location. With this Ozone data and the solar zenith angle the UVIATOR will calculate the optimal correction for every data point.

  • What is the output range of the UVS radiometers?

    • The UVS series of UV radiometers have an output in the range from 0 - 3 V.

  • Can the data from the CUV4 be used as input to calculate UV index?

    • No. According to the WMO / WHO guidelines for the Global UV Index, UV-I should only be derived from UV-E measurements (or from a spectral instrument such as our Brewer Spectrophotometer).

  • Does the UVS-AB measure UV-A and UV-B at the same time?

    • Yes, the UVS-AB has two independent detection systems.

      The UVS-AB has two continuous, simultaneous, analog outputs; one for UV-A and one for UV-B.
      See below drawing of the UVS-AB for details.

      Beneath the dome and diffuser two sets of filters and detectors are positioned. Detector 1 is 4 times bigger than detector 2. Detector 2 is located exactly in the middle, on top of detector 1. Filter 1 has an opening in the middle for filter 2 plus detector 2. In this way we can make sure both detectors have a 180 degree field of view.