Kipp & Zonen CSD1, Instruction Manual

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4. ADJUSTMENT OF THE CALIBRATION FACTOR
The following contains a procedure for adjustment of the calibration factor.
For reference see the chapter on electrical diagrams.
Calibration of CSD1 is normally performed by Kipp & Zonen.
For local calibration use a Pyrheliometer that is traceable to WRR.
In case that the user has a wider network equipped with CSD1, it is feasible
to do a simplified calibration which can serve for quality assurance.
This latter type of calibration utilises a "reference CSD1" and a solar
simulator. The "reference CSD1" is simply a CSD1 which is kept in a dark
place, and can be considered stable.
The solar simulator can be any kind of beam representing the sun. Some
laboratories might have a classified solar simulator, others might utilise a
simple slide projector. The beam spectrum should resemble the solar
spectrum as close as possible and have a small opening angle.
The procedure for calibration by the customer will generally have an
accuracy of +/- 5%. The general policy is to adjust the sensitivity of the
detectors in CSD1 only if they show a deviation from the reference that is
more than 5%, and to leave things as they are if a deviation of less than 5%
is measured.
The calibration procedure step by step:
1. Install the reference instrument in the beam of the solar simulator with
the beam covering the entire instrument, the local intensity of the beam
should be at around 500 Watts per square meter and the room
temperature at about 20 degrees. The latter specifications are not
critical, but should be stable.
2. The detector D1 of the reference is always considered to be the
reference detector. Take the average reading of J18-1 and J18-2, and
rotate the CSD1 around its axis to take a total of 4 readings at 90 degree
intervals. The average is called REF1.