When the CX-B series variable frequency constant pressure water supply automatic control device operates in variable frequency mode, the water pump motor starts to operate after soft start. The actual pressure of the water supply network is detected by a remote pressure gauge, and the actual pressure of the network is compared with the set pressure before outputting a deviation signal. The deviation signal is used to control and adjust the power frequency output by the frequency converter to change the speed of the water pump, This closed-loop control system continuously approaches the set pressure of the pipeline network, achieving constant pipeline pressure through repeated processes of continuous detection and adjustment, thereby enabling the water pump to automatically adjust the water supply according to the water demand, achieving the goal of energy conservation and water conservation

The main control function of PLC is to (1) control multiple water pumps (including backup pumps) to cycle soft start and work in a frequency conversion mode periodically; (2) Control the automatic start of the backup pump. When the first water pump motor operates in variable frequency mode and reaches the rated power (i.e. the frequency output power frequency of the frequency converter reaches 50H), but the water supply network pressure does not reach the set pressure, the second water pump motor will automatically start and operate in power frequency mode. If the network pressure still cannot reach the set pressure, the third water pump motor will automatically start, and the first water pump will still operate in variable frequency mode, To achieve the goal of maintaining constant pressure in the pipeline network, the number of water pumps put into operation is automatically controlled by the device based on the pressure of the pipeline network

The water level display controller is equipped with three water level control limits: upper, middle, and lower. When the pool water level drops from the upper limit to the middle limit position, the controller outputs a start signal of the makeup pump to make up water to the pool. When the water level reaches the upper limit, the controller outputs a stop signal of the makeup pump to stop replenishing water; When the pool water level drops to the lower limit, the controller outputs a stop signal for the water intake pump to stop taking water. After the water level rises to the middle limit, the controller automatically starts the water intake pump and resumes taking water