What the motor is and where it sits
The Siemens 1FK2104-4AK10-1SA0 is a SIMOTICS S-1FK2 HD synchronous servo motor out of the 1FK2 servomotors line built to pair with the SINAMICS S210 drive platform. The listed lifecycle stage is current, and the manufacturer status is Active — production is ongoing and the part is specified into new machine builds, not relegated to last-time-buy. Continuous stall torque M0 = 1.27 Nm with a rated power PN = 0.6 kW at nN = 6000 rpm on a 380-480 V DC link, dropping to PN = 0.4 kW at nN = 3000 rpm on a 200-240 V link. That two-tier power curve is the tell that this is the S-1FK2 HD (high-dynamic) variant — the wider speed range on the 480 V link is what makes it the right pick over a standard 1FK2 when the axis needs both low-speed torque and high-speed throughput from the same frame. The shaft is D19 x 40 mm with feather key, sealing is IP64, the feedback is an absolute single-turn 22-bit encoder (AS22DQC), and the cable exit is the OCC interface terminated through an M17 rotatable plug. The rotatable M17 connector is the field-side convenience — it lets the installer orient the cable exit to the cabinet routing without clocking the motor on the flange.
Sizing notes for the controls integrator
Holding brake is included, so the motor holds the axis at standstill when the S210 drive drops the enable — that removes an external brake on most vertical or back-driven axes but does add brake-release wiring on the OCC connector side. The 22-bit single-turn absolute encoder (AS22DQC) gives 4.19 million counts per rev for position loops, which is more resolution than most mid-range machine-tool axes need but costs nothing extra in commissioning time on the SINAMICS S210. IP64 is a dust-and-splash rating, not a washdown rating — this motor fits inside a machine cabinet or a covered gantry, not directly in a food-and-bev cell where IP67 or IP69K would be required. The D19 shaft with feather key accepts the standard range of planetary and helical gearboxes sized to the 1FK2 frame, so it drops into retrofit positions originally held by a comparable 1FK7 or third-party low-inertia servo without a re-machined mounting face.
Spares, packaging, and compliance trail
Product class C — built to order, no return-for-credit — so the BOM position needs to be confirmed before release; this is not a stocking-reseller SKU. The unit ships one piece per package at 452.00 x 250.00 x 267.00 mm, so a spare on the shelf takes a real slot in the MRO cabinet rather than fitting in a parts drawer. RoHS compliance has been on the record since 01-07-06 and REACH Art. 33 disclosure is listed as Reach Information on file with the manufacturer.