This paper describes the development of
simplified procedures for a multipyranometer array
(MPA) for the continuous measurement of direct and
diffuse solar radiation. The MPA described in this
paper is an improvement over previously published
MPA studies due several new features, including: the
incorporation of an artificial horizon that prevents
reflected ground radiation from striking the tilted
sensors, and a routine that corrects the spectral
response of photovoltaic-type sensors used in the
MPA. An optimal solution procedure has also been
developed that eliminates invalid data which are
inherent in the simultaneous solution of the solar
equations from the four MPA sensors. In this paper a
description of the NIST-traceable calibration facility
is provided and results are presented that compare the
improved MPA-predicted beam to side-by-side
measurements from a precision Normal Incidence
Pyrheliometer (NIP)
