The Omron R88ACR1B020NFE is a 20 m encoder cable accessory built for the 1S Servo Motor family — the feedback lead that runs between the drive and the motor's incremental encoder head.
Where this class of cable sits
Encoder cables on this series carry the resolver/encoder signals back to the servo drive, so the cable's length dictates the physical separation between motor and cabinet. The 20 m figure on R88ACR1B020NFE lets the drive rack sit well away from the motor — useful on long gantries, conveyor cells with remote cabinets, or any layout where the servo amplifier lives outside the immediate machine footprint.