DEW-CONDENSATION PREVENTING DEVICE IN LOW-TEMPERATURE TESTING APPARATUS

摘要

PURPOSE:To prevent dewing of moisture in air and to prevent the attachment of dew drops to an apparatus by controlling the apparatus so that the temperature of a device under test which is measured with the first temperature sensor and the temperature of atmosphere which is measured with the second temperature sensor do not exceed a specified value. CONSTITUTION:The output of a thermocouple 4 is amplified in an amplifier 8 and inputted into a converter 9. The converter 9 outputs the voltage corresponding to the temperature that is detected with the thermocouple 4 based on the characteristics of said output. An amplifier 10 and a converter 11 are connected to a thermocouple 5. The values from the converters 9 and 11 are inputted into an arithmetic unit 12. In the arithmetic unit 12, the output value of the converter 9 is subtracted from the output value of the converter 11, and the resultant value is outputted. Meanwhile, as a means for storing the value at which the difference between atmospheric temperature and the temperature of a device under test is not broadened, a setting device 13 is provided. Then, the value of the setting device 13 is compared with the output of the arithmetic unit 12 in a comparator 14. When the output of the arithmetic unit 12 exceeds the value of the setting device 13, control is performed so that the temperature does not increase. In this way, dewing of moisture in air on the device under test is prevented, and the attachment of the dew drops to the device can be prevented.