At the top of the SINAMICS G120X range, one frame — FSG — carries three ratings: 160, 200 and 250 kW. For a municipal pump station or a large HVAC plant room, that consolidation is convenient for enclosure design but unforgiving at ordering time: the three units differ in rated current, filter class and DC-terminal provision, and the order code must say exactly what you mean.
Start from the motor, then the filter, then the terminals
The sizing sequence that avoids reorders: first, match rated current to the motor at your supply voltage; second, decide who owns EMC filtering — the drive (C2/C3 integrated) or an external line reactor and filter; third, decide whether you need DC terminals for braking or a du/dt choke on long motor cables. Each decision is a digit group in the order code.
Real catalog examples show the spread: the 160 kW C2-filtered PROFIBUS DP pump drive with DC terminals and the 250 kW C3-filtered PROFINET pump drive sit in the same frame with different network and filter combinations. Both belong to the wider variable frequency drive group, and both are LO/HO-rated pump-fan drives rather than high-overload units.
C2 or C3 at this power level?
At 160–250 kW, integrated filtering is a genuine cost decision. C2 suits the first environment of industrial sites with dedicated transformer supply; C3 buys more emission headroom for the second environment near residential feeders. Unfiltered variants move the filtering to an external cabinet — the right call when a central filter serves several drives.
Do all three ratings support PROFINET and PROFIBUS DP?
Yes, as control-board variants — the network is part of the order code, not a field swap you improvise. Decide the fieldbus when ordering: retrofitting a PROFIBUS DP unit to a PROFINET plant means a board, not a parameter change.
Is 250 kW the top of the G120X family?
Yes. Beyond this class the SINAMICS portfolio moves to other families; for distributed motors in the 0.37–7.5 kW band, the wall-mount G115D covers the low end of the pump room.
