What the 400 W rating means for fit
The R88D-KT04L: The 400 W output power rating governs which servo motor this drive can pair with. In the R88D family, the drive and motor must share the same power tier — a 400 W drive mates with a 400 W R88M motor frame. Oversizing the motor without matching the drive output will stall the axis under load. The drive's power stage is sized for continuous rated torque at that 400 W level. Peak torque delivery for acceleration or deceleration typically exceeds the continuous rating by a factor of 2–3× for a few seconds, but the continuous thermal limit is the binding constraint for duty-cycle applications like pick-and-place or conveyor indexing.