Serial Communication Transmission Error

What does CALL mean?

This minor fault indicates that serial communication has not been established between the drive and the master, or that communication was interrupted. It is often caused by faulty wiring, incorrect termination resistor settings, or programming errors on the master side. If left unresolved, the drive will not be able to receive commands or send status updates, leading to system operational failure.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Review the master-side programming for communication errors, especially during start-up, and make necessary corrections.

2. 4

   Perform a self-diagnostics check on the drive; if the problem persists, the control board or entire drive may need replacement.