The invention relates to a multichannel temperature collecting
system applied to micro-gravity fluid test, comprising interface filter circuit, multichannel switching module, thermoelectric couple temperature collecting module, two-stage
signal amplifying module, A / D collecting module, couple failure detecting alarming module, central
control unit and
voltage stabilizing power supply module, where the temperature sensor is a thermoelectric couple to collect small temperature
signal and completes multichannel temperature data collection by analog switch; after passing through a thermoelectric couple
amplifier, completing
linearization and cold end compensation, and amplifying the
signal of the thermoelectric couple, where the linear output absolute value is 10 mv / deg.C, and after amplifying by the second-stage
operational amplifier, making the signal output range is 0-5 V / 10V, corresponding to the whole temperature range of the fluid testing device, such as (0-120 deg.C); converting the temperature analogue quantity into digital quantity through the A / D collecting module and inputting the digital quantity into the central
control unit. The
system is simple in structure, and has high temperature measuring stability and good consistency.