The 1.5 kW I/O Control variant is the lowest-cost entry point into the G115D range: the smallest power step, the smallest FSA frame at 380x156x129 mm, and the simplest control scheme - start, stop and a speed setpoint on plain terminals. It delivers 4.1 A continuous and 8.2 A for 3 s at 200% overload, IP65/66, with nothing on board that a simple section does not need.

What is the cheapest way to get a G115D onto a section?

Take the lowest power step in the family and remove the network port, and the price difference is the connectivity you never needed. This variant runs on terminal control: four digital inputs for start, stop, direction and an analog setpoint, two bidirectional I/O terminals for feedback, integrated Category C2 filter so external EMC hardware stays off the wiring list, and natural convection so there is no fan filter to clean. Commissioning is local - wire, set the basic parameters, run - with no network address to assign and no bus telegram list to build.

Which sections are too simple for a fieldbus?

Short transfer legs, gates, small mixers and single pumps rarely need diagnostics or remote control; they need a speed-controlled motor that starts and stops on command. Those sections pay for a network port they will never address. The two honest upgrades are both within the same 1.5 kW FSA hardware: the AB0 variant adds the fail-safe digital input for Safe Torque Off in the emergency-stop chain, and the AF0 variant brings PROFINET, PROFIsafe and EtherNet/IP for sections that will join the line. Choosing the terminal version today does not lock out either path - the drive, frame and ratings stay identical.