Specifying the 1FK2104-4AK01-1MB0 against the SINAMICS S120 line
The Siemens 1FK2104-4AK01-1MB0 is a SIMOTICS S-1FK2 HD servo motor in the 1FK2 servomotors family, sized for the SINAMICS S120 drive platform through its DRIVE-CLiQ M17 communication interface and matching M17 power connector. The motor delivers a 0.6 kW rated output at 6000 rpm on a 380-480 V bus (M0 = 1.27 Nm), with a 0.4 kW / 3000 rpm point on the 200-240 V bus, so a single SKU covers both 230 V and 400 V class line-ups without a re-spec. Shaft and feedback package are fixed: D19x40 mm shaft with feather key, absolute encoder AM22DQC at 22-bit single-turn plus 12-bit multiturn resolution — the keying, stack length, and feedback type must match the existing axis when this SKU is dropped into a replacement BOM. IP65 protection on the housing suits shop-floor deployment with splash and light dust exposure, but the rating does not extend to washdown — for hygienic or food-grade lines, the next step up in the family's sealing options is the operating constraint. Siemens lists the product as Active with a current lifecycle stage, so production is ongoing and the order code is the long-term buy, not a last-time-buy placeholder.
Ratings that drive fit on the panel and in the cabinet
The 1.27 Nm stall torque and 0.6 kW continuous rating sit at the compact end of the 1FK2 family — this is the high-dynamic servo frame for short-cycle motion, not a heavy-duty spindle drive, and the duty cycle has to be checked against the application's RMS torque at peak. At 6000 rpm on the 380-480 V bus the motor keeps a flat torque plateau typical of SINAMICS S120 matched servos, which is what gives the dynamic response the 1FK2 HD series is specced for in pick-and-place, packaging, and small-format converting axes. The AM22DQC encoder returns absolute position across power cycles, so the controller does not need a homing routine after every E-stop or mains dip — a concrete advantage on machines with frequent mode changes. Packaging ships one piece per carton at 452.00 x 250.00 x 267.00 mm — sized for standard parcel freight rather than palletized container loads, which keeps the inbound logistics simple for a service spare or single-axis retrofit.
Compliance posture for cross-region builds
RoHS compliance has been in force since 01-07-06 and REACH Article 33 disclosure is maintained per the current candidate list, so EU and most APAC builds accept this part without a separate substance declaration file. Export control is rated AL:N / ECCN:N_CNDU, which means no special export licence is required for typical cross-border industrial shipments — a routine paperwork note for the logistics planner. Siemens classifies the order as product class C — manufactured to order, non-returnable for credit — which sets the procurement expectation that lot sizes and cancellations follow the factory's build cycle rather than shelf inventory.
Procurement and order administration
Group Code R220 and Product Group 9021 are the internal Siemens ordering slots, useful when raising the line on a Siemens portal or matching it against an existing frame agreement.