Cooling function: an important part of the high and low temperature cycle impact test chamber, which is an important parameter for determining the performance of a constant temperature and humidity machine. It includes four components: compressor, condenser, throttling device, and evaporator; The compressor is the heart of the refrigeration system, which sucks in low-temperature and low-pressure gas, turns it into high-temperature and high-pressure gas, condenses it into liquid to release heat, and takes away the heat through the fan. Therefore, under the constant temperature and humidity machine, there is hot air, and then it is throttled to become low-pressure liquid. Secondly, it becomes low-temperature and low-pressure gas through the evaporator and returns to the compressor; The refrigerant absorbs heat in the evaporator to complete the gasification process and absorb heat, achieving the purpose of refrigeration and completing the cooling process of the constant temperature and humidity machine. Heating function: The heating device controls whether the high and low temperature cycle impact test chamber is a key link in heating up; It outputs a voltage to the relay when the controller receives a temperature command, with approximately 3-12 volts of DC applied to the solid-state relay; Its communication end is equivalent to a wire connection; The contactor also simultaneously engages, and there is voltage at both ends of the heater to generate heat. The heat is carried into the box by the circulating fan, which heats up the high and low temperature cycling impact test box; The temperature is about to reach your set value; The controller adjusts the on-off state of the solid-state relay by adding it; We adjust the heat output by observing the heating output on the screen of the programmable high and low temperature cycling testing machine; This is temperature control above 89 degrees, how to control temperature stability below 89 degrees? The programmable high and low temperature cycle testing machine generates heat and output through solid-state relays on one side; Furthermore, dynamic equilibrium is achieved by cooling through a compressor refrigeration cycle; The temperature remains constant.

Humidification function, dehumidification function: The dehumidification system is also completed by the refrigeration system, and the evaporator is placed in a programmable high and low temperature cycle testing machine; Relatively cold, the programmable high and low temperature cycle testing machine condenses high humidity gas into liquid when it meets cold objects; The high humidity gas in the box will be reduced repeatedly, achieving the purpose of dehumidification.

The error of programmable high and low temperature cyclic testing machine mostly refers to measurement error, which is traditionally defined as the difference between the measurement result and the measured true value. It can usually be divided into two categories: systematic error and accidental error. Error is objectively present and should be a definite value, but in the vast majority of cases, the true value is unknown, so the true error cannot be accurately determined. We only seek approximate truth values under specific conditions and refer to them as agreed truth values.

The difference between the correction of measurement results by programmable high and low temperature cyclic testing machines: the term "uncertainty" itself implies an estimable value, which does not refer to a specific or exact error value. Although it can be estimated, it cannot be used to correct the quantity value. Only the uncertainty introduced by incomplete correction can be considered in the uncertainty of the corrected measurement results; If the estimated value of system error is known, the measurement results can be corrected to obtain the corrected measurement results.

After correction, a quantity may be closer to its true value, but its uncertainty not only does not decrease, but sometimes it may even increase. This is mainly because we cannot know exactly what the true value is, and can only estimate the degree to which the measurement results of the programmable high and low temperature cycle testing machine approach or deviate from the true value.