The 6SL3520-0XH65-5AF0 occupies the entry rung of the FSC frame in the SINAMICS G115D family — a 5.5 kW distributed wall-mounted frequency converter with a 13.2 A rated output. It is the bridge between the FSB (up to 4 kW) and the full-power 7.5 kW FSC. For conveyor sections that exceed the 4 kW thermal ceiling of the FSB but do not need the full 7.5 kW, the 5.5 kW FSC is the correctly sized choice. It shares the same FSC enclosure as the 7.5 kW — 425 × 240 × 169 mm with an integrated thermostatically controlled fan and built-in brake chopper — so the mechanical footprint is identical regardless of which FSC power rating is selected.

When does the 5.5 kW FSC make more sense than the 7.5 kW?

The only difference between the 5.5 kW and 7.5 kW FSC variants is the output current rating — 13.2 A versus 19 A. The frame, cooling, brake chopper, safety features, and communication interfaces are identical. If the motor nameplate current is under 13.2 A, the 5.5 kW model is the correct fit — selecting the 7.5 kW would provide no performance benefit while increasing the component cost. The 5.5 kW is commonly paired with medium-duty conveyor sections: accumulation zones, merge tables, inclined belts with moderate slope, and transfer carts where the mechanical load is substantial but below the 7.5 kW threshold.

What changes when moving from the 4 kW FSB to the 5.5 kW FSC?

Three things change at the FSB-to-FSC boundary. First, cooling: the FSC adds an integrated thermostatically controlled fan, where the 4 kW FSB uses a smaller integrated fan and the 2.2–3 kW FSB models are passively cooled. Second, the integrated braking resistor is larger — the FSC frame is rated 20 W continuous / 200 W peak, against 10 W / 100 W for the FSB, and it accepts an optional external braking resistor (minimum 40 Ω). Third, the current reserve increases: 13.2 A at 5.5 kW versus 10.2 A at 4 kW, a 29% step up that corresponds to a real difference in the conveyor sections the drive can handle. The enclosure width is the same (425 mm), so the change is electrical and thermal rather than spatial.

Frequently Asked Questions

What is the difference between the AF0, AB0, and AA0 suffixes on the 5.5 kW model?

The suffix codes designate the I/O interface configuration — the type and arrangement of digital inputs, outputs, and communication connectors populated on the unit. The 5.5 kW power rating, 13.2 A output, 380–480 V supply, 0–550 Hz frequency range, FSC frame dimensions, integrated brake chopper, and integrated safety functions are identical across AF0, AB0, and AA0. The choice is a field-wiring decision: consult the G115D operating manual for the terminal assignment of each suffix variant.

Can the 5.5 kW G115D brake a high-inertia load without an external resistor?

The converter has an integrated braking resistor rated 20 W continuous / 200 W peak, so light braking with extended ramp times can be handled without an external resistor. The chopper is the switching element; the resistor is the energy-dissipating element. For frequent stops, high inertia, or short deceleration ramps, an external resistor matched to the load is required. The minimum resistance for the FSC frame is 40 Ω; the actual resistor wattage depends on the duty cycle and the kinetic energy of the load.