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Central air conditioning PLC control cabinet operation principle

Categories:Company News
Time of issue:2023-09-12

(Summary description)Temperature control: Based on the difference between the return air (or typical room) temperature and the preset value

Central air conditioning PLC control cabinet operation principle

(Summary description)Temperature control: Based on the difference between the return air (or typical room) temperature and the preset value

Categories:Company News
Time of issue:2023-09-12

Information

1. Temperature control: Based on the difference between the return air (or typical room) temperature and the preset value and the optical rotation, adjust the opening of the cold/boiling water valve and the operating frequency of the fan according to the PID calculation value of DDC to achieve the measured target temperature Maintain within prescribed limits.

2. Humidity control: Based on the difference between the return air (or typical room) humidity and the preset value and the optical rotation, adjust the humidification valve opening according to the PID calculation value of DDC to maintain the measured target humidity within the specified range. Inside.

3. Environmental protection and energy-saving control: According to the tested temperature and humidity of fresh air and return air (or typical room), the dew point temperature is calculated according to DDC, and the fresh air valve and exhaust air are adjusted according to the dew point temperature and humid heat load of the fresh air and return air. The opening ratio of the valve and return air valve and the operating frequency of the fan enable the central air conditioner to operate throughout the season.

4. Interlock control: The fresh air valve, return air valve, cold/open water valve, humidification valve, etc. are all interlocked with the fan. When the fan is started and started, the opening of the fresh air and other gate valves is adjusted; when the fan is shut down, the fresh air valve, The cold/open water valve, humidification valve, etc. are also turned off.

5. Detect: fresh air/return air/exhaust air/temperature and humidity of typical rooms, opening of electric air valve/water inlet valve, fan operation and operation status, etc.

6. Alarm: Common fan failure alarm, filter device obstruction alarm, ultra-low temperature alarm, fire safety shutdown.