This week the team conducted a temperature test of the LimeSDR flight hardware in a thermal chamber. The goal of the test is to demonstrate that the housing will not exceed safe surface temperature when ESA astronaut Alexander Gerst handles the experiment. There is an upper temperature limit of 45 ºC, but the team designed the housing to never go above 40 ºC in the highest ambient temperatures.
So the housing, containing the LimeSDR, was placed in a thermal chamber for several hours. During this time, the ambient temperature was set as high as 35 ºC and as low as 22 ºC. Throughout this range, the LimeSDR was put into operational and standby mode. The team recorded temperatures on the top and side of the housing at various time intervals via attached temperature sensors.
Just like with last week’s initial touch temperature test, the housing remained with the safety margins. The top of the housing within the grid structure reached a maximum of 40.7 ºC within the 35 ºC ambient temperature. Considering that it is likely that the temperature in the Columbus module will never be as high as 35°C under normal operations, we are way below the limits set by NASA/ESA.