E44.02 fault in inovance IS580 drive indicates Speed sensor fault. This means the drive is not receiving valid or reliable feedback from the connected speed sensor — such as an incremental encoder or resolver — while operating in closed-loop control mode.

• Check all connections for tightness and continuity.
• Inspect for bent pins, damaged cables, or EMI noise.
• If possible, swap the encoder with a known-good one to verify the issue.