Mitsubishi Electric 800 Series Instruction Manual page 70

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 enable" command, changing the mode to the PU
operation mode with switchover function does not allow the "network operation mode enable" 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 enable" from the master once, then send the "network operation
mode enable" command again.
8
69
PPO TYPE NON-SUPPORT SPECIFICATION