The basic components of a pumping station include: machine room, collection tank, grille, auxiliary room, and sometimes even a substation. Install water pump units and related ancillary equipment in the machine room; The grille and suction pipe are installed inside the water collection tank, which can also regulate the unevenness of incoming water to a certain extent, so that the water pump can work more evenly; The function of the grille is to block large solid impurities in the water, in order to prevent them from blocking and damaging the water pump.
The pump station mainly adopts buried installation and intelligent real-time monitoring. There are multiple classification methods for pumping stations. According to the nature of their drainage, pumping stations can be divided into intermediate pumping stations (or regional pumping stations) and terminal pumping stations (or main pumping stations). Intermediate pumping stations are located along the sewage pipeline and are usually set up to avoid burying the drainage main pipe too deep. The terminal pumping station is located at the end of the drainage system, pumping all sewage to the sewage treatment station or irrigating farmland or directly discharging the treated sewage into water bodies; According to the combination of the collection tank and the machine room, the drainage pumping station can be divided into a combined pumping station and a separate pumping station; According to the control method, drainage pumping stations can be divided into divided control pumping stations and automatic control pumping stations.
Next, let's talk about the four control methods for the operation of pump units in integrated prefabricated pumping stations:
1. Fully automatic control mode
In this way, the PLC automatically controls the number and sequence of water pumps based on the water level of the collection tank and the process parameters set by the computer according to the pre programmed program, maintaining the work balance between the collection tank and the four submersible pumps within a certain water level range. The electric valve and the pump motor are linked. After the water pump is turned on, the electric valve automatically opens, and after the pump is stopped, the electric valve automatically closes.
3. Local manual control mode
In this way, both the submersible pump and the electric valve are controlled by the control buttons on the local control box to start and stop. The PLC system only monitors these devices, liquid levels, and flow rates, and cannot control them. This method is generally only used for debugging or maintenance.
2. Soft starter and protection
Each water pump is equipped with a soft starter in the main control circuit, which uses thyristors (thyristors) to control the motor terminal voltage during starting, reducing the starting impulse current and accelerating torque, making the water pump start stable and smooth, and increasing the service life of the equipment. In addition, soft starter equipment is used.
4. PLC remote manual control
In this way, the operator uses a computer keyboard or mouse to control the start and stop of the submersible pump and electric valve through PLC. This control method only allows the operator to control the equipment without going to the site. It is only an extension or transfer of the local control button, usually used for debugging or maintenance.
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