Quanzhou Ausenist Technology Co., Ltd How Does AU620 Inverter Achieve Master-Standby Auto-Switching?
The AU620 system achieves master-standby auto-switching through its built-in multi-pump control logic and real-time RS485 communication detection.
Below are the core steps and mechanisms for implementing auto-switching:
1. Basic Hardware Configuration
- Dual Sensor Installation: In the master-standby system, both the master drive (Address 1) and standby master drive (Address 2) must be independently equipped with pressure sensors. This ensures that when either unit acts as the "master" leader, it can obtain real-time pipe network pressure data.
- Communication Parallel Connection: All drives must be physically connected in parallel via RS485 communication cables (S+ to S+, S- to S-) to form a data interaction network.
2. Normal Operating Mode
- During normal system operation, the master drive (Address 1) is in the dominant position, responsible for pressure detection and PID calculation.
- The standby master drive (Address 2) acts as an "auxiliary drive" at this time, receiving PID feedback and start/stop commands from the master drive via RS485 to cooperate with operation.
3. Auto-Switching Logic (Fault Transfer)
The system triggers the auto-switching mechanism when the following specific conditions are met:
- Fault Detection: If the master drive fails (e.g., hardware damage, error reporting), the sensor malfunctions, or communication is interrupted.
- Logic Handover: The system uses "Fault Shift" logic. After detecting the master drive failure, the standby master drive will automatically upgrade to the "master" after waiting for the time set in parameter U3-07 (Standby Master Start Delay, default 5 seconds).
- Takeover Control: The upgraded standby master drive will enable its own connected sensor signal to direct the remaining auxiliary drives to continue maintaining constant pressure water supply.
4. Key Parameter Settings
To ensure auto-switching takes effect, the standby master drive (Address 2) usually needs the following configurations:
- Local Address (U3-01): Set to 2.
- Control Mode (U0-10/U0-13): Set to 2 (Communication Control), allowing it to follow the scheduling of Address 1 during normal operation.
- Delay Setting (U3-07): Adjust the response time for the standby master drive to take over the system according to requirements.
Summary
With this dual-master redundancy design, AU620 ensures that the water supply system can seamlessly switch and continue to operate stably when core equipment fails suddenly.