Apogee Instruments TS-200 Руководство пользователя - Страница 7
Просмотреть онлайн или скачать pdf Руководство пользователя для Оборудование для обеспечения безопасности Apogee Instruments TS-200. Apogee Instruments TS-200 20 страниц. Fan-aspirated radiation shield
Печатать страницуSPECIFICATIONS
TS-200/210/220/230
Radiation-induced Temperature Increase (RITI):
There is no reference standard for the elimination of radiation effects on air temperature measurement, but well-
designed fan-aspirated shields minimize this effect. In the absence of a standard, radiation-induced temperature
increase (RITI) was analyzed in long-term experiments over snow and grass surfaces by comparing temperature
measurements from nine replicate Apogee Instruments model TS-200 shields to measurements from two replicate
fan-aspirated shields from Met One (model 076B) and two replicate fan-aspirated shields from R. M. Young (model
43502). Comparisons among shields were made with ST-110 thermistors in all shields. Despite careful placement of
shields away from each other and the tower (see photo below), and filtering for wind direction, these experiments
indicate that there is more variability among replicate shields (± 0.1 C) of the same model than between models of
shields (± 0.05 C), thus there is no statistical difference among the three models of shields.
Field tests indicate that low wind speed has a greater effect on RITI than high radiation load. For conditions of solar
-2
-1
radiation greater than 800 W m
and wind speeds less than 2 m s
, the mean of the model TS-200 shields has
been within 0.05 C of the means of the other two models of shields. At higher wind speeds, the TS-200 and R. M.
Young shields read slightly cooler (-0.05 C) than the mean of the Met One shields, but the difference is not
statistically significant.