The drive is not detecting a valid encoder signal. Check for and correct:
• Encoder presence and proper connection (reverse wired = channel A
connected to terminal of channel B or vice versa, loose connection or
short circuit).
• Voltage logic levels are outside of the specified range.
• A working and properly connected Pulse Encoder Interface Module,
OTAC-01.
• Wrong value entered in parameter 5001 PULSE NR. A wrong value will
only be detected if the error is such that the calculated slip is greater
than 4 times the rated slip of the motor.
• Encoder is not being used, but parameter 5002 ENCODER ENABLE =
1 (ENABLE).