What it is
The Omron R88ACA1E020BFE is a power cable in the R88A-CA1 family, built as an accessory for 1S Servo Motors and listed for stepper motor and servo accessory use. It carries the motor power conductors together with the brake conductors in a single 20 m run rated for 400 V service, which is what the integrator confirms against the drive's motor output rating before pulling it into the panel.
Where it sits in a 1S system
Cables in this family are the motor-side link between an Omron 1S servo drive and its matching 1S servo motor, so the R88ACA1E020BFE is the line that gets terminated at the drive end and dressed through the cable chain on the machine.
Compared with the 10 m brake cable
R88ACA1A020SFE and R88ACA1G010SF are further same-family power cables for 1S Servo Motors, but they sit on different sub-series — one without the brake conductor suffix, the other on a different cable family — so neither is a drop-in replacement on a panel already specified for the R88ACA1E brake-cable format.