When the system is configured in "Dual Master Drive (two master drives + up to four auxiliary drives)" mode, the fault transfer logic operates as follows:

• Trigger Conditions: The system detects the following situations in the primary master drive (Address 1):
  • Hardware damage or inoperability of the master drive.
  • Protection or failure of the pressure sensor of the master drive (sensor damage).
  • Interruption of communication signal between the master drive and other pumps.
• Activation Process: Once the trigger conditions are met, the standby master drive (Address 2), which was originally in the role of an auxiliary drive (auxiliary working state), will automatically upgrade to "master drive" and take over the command of the entire system.
• Switching Delay: This process is controlled by the function code U3-07 (Standby Master Start Delay/Valid Delay), with a factory default value of 5.0 seconds.
• Hardware Foundation: For this logic to take effect, both master drives must be independently equipped with pressure sensors to independently detect pipe network pressure after taking over the system.

When an auxiliary drive (slave drive) in the system fails, the logic is as follows:

• Detection Method: The master drive monitors the operating status of all auxiliary drives in real time through the extended RS485 design.
• Activation Process: If a certain auxiliary drive fails, the system logic will directly skip the faulty pump and automatically start the next available auxiliary drive.
• Non-interference: The failure of any auxiliary drive will not affect the linkage operation of other normal pump groups, thus ensuring that the automatic rotation and pump adding/reducing logic of the pump group are not hindered.