I. Overview
Water supply applications are extremely wide-ranging, including road irrigation, domestic water supply, industrial water supply, and construction site water supply.
Inverter control. The quality of water supply inverters varies greatly, with a lack of reliable options, which provides a good entry point for our AC300. Water supply solution comparison.
It is standardized and relatively easy to maintain.
II. Equipment Composition and Working Principle in the Water Supply Industry
The constant pressure water supply system mainly consists of a motor, a water pump, a buffer tank, a remote pressure gauge, and an AC300 frequency converter.
Generally, terminal start/stop is used. Constant pressure water supply systems compare the feedback signal from a remote pressure gauge with a setpoint; when the feedback value is higher than the setpoint, the system will initiate a shutdown process.
When the threshold is reached, the inverter enters sleep mode after the sleep period. When the feedback threshold falls below the start threshold, the motor restarts.
Movement. To keep the pressure near a given value.
III. Functions to be achieved in the constant pressure water supply industry.
The main function of constant pressure water supply is to maintain a constant water pressure and prevent large fluctuations.
Main functions to be implemented:
(a) Pressure setting, that is, the setting of kilograms.
(ii) To achieve a hibernation function, the motor maintains a low speed or zero speed when water is not in use.
(iii) When the pressure feedback is lower than a certain value, it is necessary to restart to maintain the pressure.
IV. Application of AC300 in the constant pressure water supply industry.
Parameter settings:
plan:
1. F00.03=8 (Frequency setpoint channel is set to: PID control setpoint).
2. Set the PID controller's input signal source; (For example: for a 10 kg water tank, to maintain a constant pressure of 6 kg; then set the input signal to 6/10 + F11.32).
(If F11.32 is 5% at this time) = 65%; if the constant pressure is 6 kg and does not require too much precision, and the wake-up deviation is small, the given value can be directly set to 6/10 = 60%).
3. Set up the feedback signal source for the PID controller (voltage-type pressure gauge or current-type pressure gauge, etc.).
4. F11.29=1; (Constant pressure water supply in hibernation mode is effective).
5. Set the sleep frequency to F11.30 based on the local settings; (if the output frequency is lower than the sleep frequency, it will enter hibernation via F11.31).
6. Set sleep delay to F11.31 based on the site settings.
7. Set the wake-up deviation for F11.32; (When the PID setpoint - wake-up deviation > PID feedback, sleep mode will be stopped and the system will start).
8. Set wake-up delay; (When the PID setpoint - wake-up deviation > PID feedback, the system will no longer sleep after the set wake-up delay time.)
The frequency converter will start.
V. Conclusion
The constant pressure water supply system utilizes the PID control function of a frequency converter. Previously, constant pressure water supply mainly used AC60 and AC70 frequency converters to achieve constant pressure.
While meeting water requirements, the AC300 frequency converter offers superior control performance in constant pressure water supply, as our company excels in the AC300 general-purpose frequency converter.
The PID control algorithm has been optimized, resulting in better PID control performance, higher accuracy, and faster dynamic response, thereby enabling excellent process control and ensuring...
Reliability of process control.
