Points To Note - Mitsubishi Electric FR-E5NP Instruction Manual

7.4.1 Points to note

Only when the contents of the command request (request for changing the inverter setting: PKW) from the
master changed, the inverter processes the request. If the contents of the command request are identical
with those of the last request, the inverter does not process the request. (The received request is cleared.)
For instance, while the master keeps sending the "network operation mode enabled" command,
changing the mode to the PU operation mode with switchover function does not allow the "network
operation mode enabled" command to be executed due to the same contents as that sent last time.
Therefore, the operation mode remains the PU operation mode without changing to the network
operation mode.
In this case, send another command as "PU operation mode enabled" from the master once, then send
the "network operation mode enabled" command again.
Profibus PROFILES—PPO Non Support Specification
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