CM 121 Shadow Ring for the measurement of diuse radiation Suitable for all latitudes and surfaces in the tilted North-South plane Compatible with all CMP/SMP series pyranometers, CGR pyrgeometers and CUV 5 UV radiometer View angle of 10.6 ° CM 121 is a shadow ring that does not require power and can be used with all the Kipp & Zonen CMP, SMP, CGR and CUV series of instruments. It is used for measurements of the diuse sky radiation or to shade a pyrgeometer from the direct solar radiation. CM 121B is for unventilated radiometers and CM 121C is for ventilated instruments. The radiometer is installed on the mounting pedestal and after levelling and correct adjustment for the location and the sun declination the ring makes a shadow on the radiometer dome throughout the day. To maintain the shading accuracy it is necessary to adjust the position of the ring every few days to compensate for changes in the solar arc.

The ring has a width / diameter ratio of 0.185 and has a view of 10.6° seen from the radiometer. Because the ring intersects a part of the diffuse sky, a table is supplied to compensate the measured values. A measuring radiometer is not included, and must be ordered separately. Go to www.kippzonen.com for your local distributor HEAD OFFICE ■^■^■^■^■^■^■^■^■^■^■^■^■^■^■j Zonen ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^H Delftechpark 2628 XH Delft ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^H Kipp & Zonen B.V. reserve the right to alter specifications of the equipment described in this documentation without prior notice...