EKO INSTRUMENTS CO., LTD. MS-56 Pyrheliometer Manual Ver.5
Pg. 6
4. Introduction
4 - 1 . I n t r o d u c t i o n
The ISO9060 First Class MS-56 is a research grade normal incidence direct solar irradiance sensor also
known as a pyrheliometer or DNI sensor which highly suitable for routine operation on automated Sun Tracker.
The all-weather MS-56 is sensitive to solar irradiance throughout the spectral range 200 to 4,000nm and can
work under most extreme conditions in a temperature range from -40°C to +80°C.
In principle to perform high precision direct solar radiation measurements under non-stable atmospheric
conditions, ideally a fast responding detector is required to detect quick radiation changes. Although
photodiode type detector offer a quick response but it has a limited spectral sensitive range; in contrary
thermopile broad band detectors cover the full spectral range, but it is considered to be slow. The versatile
MS-56 combines all those features of a quick broadband detector enabled by an advanced technology
thermopile detector. It combines a unique fast response time (<1s 95%), high sensitivity, excellent thermal
stability and very low temperature coefficient to make it hardly immune to ambient temperature variations,
therefore it is suitable to be used in a wide temperature range.
The MS-56 has a standard full 5° (degrees) opening angle and 1° slope angle as defined by ISO
Pyrheliometers Standards and greatly performs when used in combination with the EKO STR-21(G) or
STR-22(G) Sun Tracker. The standard built-in thermistor (44031,
10kΩ@25
℃
) or platinum resistance
temperature sensor (Pt100, Class A, IEC751 compliance) can be used as a temperature reference for
extensive research purposes. The integrated low power window heater prevents dew deposition or frost on
the outside window.
The MS-56 has a robust but compact and smooth design which forms the new generation of EKO Instruments
solar radiometers that are designed for most demanding Photovoltaic and Meteorological applications at any
place on earth.
Each MS-56 is calibrated and tested at EKO upon manufacture aga
inst EKO’s reference sensors which are
fully traceable to the WRR (World Radiometric Reference) maintained at the PMOD/WRC
(Physikalisch-Meteorologisches Observatorium Davos/World Radiation Center) in Davos, Switzerland.
