38.1299
Internal Fault: Option software in slot A too old
Danfoss · VLT HVAC-FC 102 Frequency Converter
What does 38.1299 mean?
The software version on the option card installed in slot A is detected as being outdated or incompatible with the frequency converter's current firmware. This mismatch can lead to communication errors, incorrect functionality, or complete failure of the option card.
Source: Danfoss VLT HVAC-FC 102 Frequency Converter
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