Industry Overview
In the water supply system, constant pressure water supply refers to a control method that controls the outlet pressure to remain unchanged at a set value when the water pressure in the water supply network system changes by detecting the pressure of the pipe network. When the pump is generally used, the rated flow rate of the selected equipment usually exceeds the actual required flow rate, and the flow rate required during actual water use will change. For example, in the building water supply, the amount of water used during day and night changes greatly, and valves are used. The method of adjusting the flow rate is more commonly used. Although the method is simple, this method actually achieves the goal of adjusting by artificially increasing the resistance. This kind of throttling regulation method wastes a lot of electric energy, and increases the cost of equipment use and maintenance.
Working principle analysis
The constant pressure water supply system detects the pressure of the pipe network through the pressure sensor, and feeds it back to the inverter in the form of voltage or current (0-10V or 4-20mA). The built-in PID is used to compare the set pressure and feedback pressure of the user, correspondingly. Adjust the output speed of the motor so as to achieve the constant pressure effect. In the evening when the water consumption is very low and the water pressure does not affect the user's use, the entire system enters the dormant state, after the water pressure drops to a certain value and keeps the pressure over a certain period of time. Can wake the system automatically.
Scheme electrical diagram
Parameter setting
System scheme advantages
1. Built-in PID function can automatically detect the water pressure according to the user's actual water consumption and realize constant pressure water supply
2. With built-in dormancy function, the frequency conversion water supply system can automatically enter the hibernation state when the water consumption is small and does not affect the normal use of the user. When the water pressure drops to a certain value, the water pump can wake up automatically to meet the energy saving and consumption reduction requirements.
3, can achieve a constant pressure pipe network, to avoid the excessive pressure caused by the traditional water supply pipe network and faucet resonance phenomenon.
4. No need for water supply water tanks, which occupies a small space, low investment costs, and avoids secondary pollution of water quality.
5, start smooth, small impact on the power grid and motor water pump, to avoid the water hammer phenomenon, greatly increasing the service life of the pump.
6, a full range of protection features, such as: undervoltage, overcurrent, overload, overheating, lack of phase, short circuit protection.