Working Principle Of Purifying Hot Air Circulation Oven

The working principle of the purifying Hot air circulation oven: When the temperature reaches the set value, the temperature controller outputs the PID control signal PLC, and the PLC outputs the control signal to the time relay KT to start the heat preservation time. At the same time, close the inlet fan and exhaust disc valve . The electric heating is continuously opened and closed through PID control, and the box is in the heat preservation stage of hot air circulation. When the heat preservation time reaches the set value, the time relay outputs a signal to the PLC, and the PLC outputs a fully closed electric heating. The water cooling solenoid valve is opened to make it close and conduct, so that the box is in the cooling stage.

The temperature control of the box adopts the GCD-23A intelligent computer temperature control and PLC automatic control system. The temperature signal is collected by platinum resistance. The PID control signal is obtained after the amplification of the temperature controller and the set value, and the PLC program controller outputs at the same time The control signal controls the solid-state relay SSR to turn on, and the solid-state relay controls the heater to heat, so that the cabinet is in the heating and dehumidifying stage.

When the temperature in the box drops ≤40℃, the temperature controller will output a control signal to the PLC, and the PLC output will turn off the hot air circulation fan, and the drying cycle program will end. The output signal of TEED-2001K over-temperature alarm temperature controller controls the operation of the entire PLC program. The platinum resistance PT100 test signal to the alarm temperature controller is compared with the over-temperature alarm set temperature value. When the actual temperature value is lower than the set value, the output The control signal is given to the PLC, and the PLC program runs normally. When the actual temperature value exceeds the set value, the control signal is output to the PLC, and the PLC closes the running program. Therefore, the setting value of the over-temperature alarm is generally higher than the setting value of the working temperature.