Serial Link Failure

What does -SLF mean?

This fault occurs when communication is lost between the drive controller and its connected serial devices, such as a remote keypad display or a MODBUS master controller. This prevents external control, monitoring, or parameter adjustment of the drive, interrupting automated processes. The cause could be physical disconnection, incorrect settings, or device malfunction.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Ensure the remote keypad or MODBUS controller is powered on and functioning correctly. Check its own status indicators for errors.