Evaluation of Performance of Solar Powered Flashing Beacons at Severe Temperature ConditionsAuthor/Presenter: Medina, Juan; Benekohal, Rahim; Hajbabaie, Ali
This report contains the results of 34 tests for JSF and 26 tests for Carmanah solar-powered flashing beacons operating in mild cold temperature (-6.6 ºC), severe cold temperature (-20 ºC), and hot temperature (+70 ºC) conditions. In addition, it contains two tests for JSF modules and two for Carmanah operating under “real world” conditions. In mild temperature condition, red and yellow modules of JSF flashed in MUTCD pattern for at least 11 and 8.5 days, respectively. The red and yellow modules of Carmanah flashed in MUTCD pattern for at least 11 and 8 days, respectively. Reducing the temperature to -20 ºC resulted in a significant decrease in the duration of flashing in MUTCD pattern for JSF modules; however, that duration did not decrease for Carmanah. Red and yellow modules of JSF flashed in MUTCD pattern for at least 18 and 24 hours in severe cold temperature condition. For Carmanah, red and yellow modules lasted in MUTCD flashing pattern for at least 14 and 11.5 days, respectively. In hot temperature condition, red and yellow modules of JSF flashed in MUTCD pattern for at least 6.5 and 5.5 days, respectively. Red and yellow modules of Carmanah lasted in MUTCD flashing pattern for at least 8.5 and 7 days, respectively. The “real world” condition test indicated that in certain conditions (e.g. solar panels covered with snow), the solar panels may not be able to generate enough power for the LEDs to keep them flashing in MUTCD pattern. In this condition, the flashing pattern changes to a power saver mode. The red modules of JSF and Carmanah were visible when the distance was at least 1500 ft in a sunny and very bright day. The yellow modules of JSF and Carmanah were visible up to a distance of about 1000 ft in the same day. If solar panels are accidently disconnected when the modules are outdoors and batteries are fully charged, the JSF and Carmanah modules were visible at a distance of 700 ft, in a cloudy but bright day.