6684
EFB load fault
ABB · ACS880 Primary Firmware
What does 6684 mean?
The embedded fieldbus (EFB) protocol firmware could not be loaded, or there's a version mismatch between the EFB protocol firmware and the drive firmware. This means the EFB functionality is completely disabled. The drive cannot communicate via EFB.
Source: ABB ACS880 Primary Firmware
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