Err 21.1 Encoder communication error fault in panasonic drive

Cause: The drive sees the encoder, but data is corrupted by electrical noise.

Remedy:

• Separate encoder signal cables from high-voltage motor/power cables.
• Ensure the encoder cable is a twisted-pair shielded type.
• Install a ferrite core on the encoder cable near the driver.
• Check if the earth ground (PE) is clean.