General Information; Introduction - Kipp & Zonen CM 11 Instruction Manual

1.

GENERAL INFORMATION

1.1

INTRODUCTION

The pyranometer CM 11 is designed for measuring the irradiance
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(radiant-flux, Watt/m ) on a plane surface, which results from the
direct solar radiation and from the diffuse radiation incident from the
hemisphere above.
Because the CM 11 exhibits no tilt dependence it can measure solar
radiation on surfaces inclined as well.
In the inverted position reflected solar radiation can be measured.
The albedometer CM 14 is based on two CM 11 sensors and is
suitable for the measurement of net global radiation and/or albedo
over surfaces of different nature (see chapter 5 for installation).
For measuring the diffuse component of solar radiation only, the direct
solar component can be shielded semi-automatically from the
pyranometer by the Kipp & Zonen shadow ring CM 121, and fully
automatically by the 2AP tracker with shading system.
The CM 11 pyranometer complies with the specifications for 'High
quality', the best of three classes, as published in the 'Guide to
meteorological Instruments and Methods of Observation', Eight
edition, 1996, of the World Meteorological Organization (WMO) -
Geneva - Switzerland.
The WMO classification list is adopted, improved and extended by the
International Standard Organization ISO and published as ISO 9060.
This standard is one of a series of standards specifying methods and
instruments for the measurement of solar radiation.
In this manual the specifications of accuracy are listed according the
ISO 9060, in which the CM 11 is classified as a "secondary standard"
list.
GENERAL INFORMATION
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