The SINAMICS G115D 6SL3520-1XA21-5AA0 is the 1.5 kW wall-mounted distributed frequency converter in FSA frame with I/O Control — the highest FSA power rating in the SINAMICS G115D series, configured with the simplest hardwired control interface. At 1.5 kW FSA (380 × 216 × 129 mm), natural convection through the IP65-sealed aluminum housing sustains continuous operation without a fan — this is the FSA power ceiling; beyond this, the drive steps up to the larger FSB frame. It delivers 4.1 A rated output with 200% overload, driving IE3/IE4 motors via SIMOGEAR 2KJ8 direct mounting. I/O Control (AA0) provides discrete digital inputs for run/stop/direction/fixed speeds, analog input for speed reference, and F-DI for STO — no fieldbus protocol, no network configuration, just terminal-block wiring to the PLC I/O cards.

When is I/O Control the right choice at the FSA power ceiling?

At 1.5 kW — the highest FSA rating, covering the majority of light-to-medium conveyor zones — the AA0 I/O Control variant suits three scenarios: (1) the PLC cabinet is within wiring distance of the conveyor zone, making discrete wires simpler than fieldbus configuration; (2) the machine builder standardizes on hardwired I/O for commissioning simplicity across all drive sizes; (3) the end user specifically requires I/O Control for compatibility with existing plant wiring standards. The 1XA21 code in the 1XA series identifies this variant — paralleling 1XA01 AA0 for the same 1.5 kW FSA hardware.

Frequently Asked Questions

Can I add a fieldbus to this drive later?

No — the AA0 variant has no fieldbus interface hardware. To migrate to AS-Interface or PROFINET, replace with the AF0 or AB0 variant.

What is the difference between 1XA21 and 1XA01?

Catalog designation only. Both identify the same 1.5 kW FSA hardware — mechanically and electrically identical. Drives are functionally interchangeable.