What lands on the rack
The part is the Siemens 6SL3120-2TE21-8AA3, a SINAMICS S120 booksize double motor module flagged as a spare part — it accepts a 600 V DC link and delivers 400 V three-phase output at 18 A on each of its two motor axes, which is how S120 doubles servo density inside a single slot rather than pairing two single-axis modules. It carries the line's internal air cooling, optimized pulse patterns, the extended Safety Integrated functions and a DRIVE-CLiQ cable for the digital link back to the control unit — so the slot on the rack is the only thing to plan for before the drive is commissioned.
Reading the 18 A / 18 A rating
Two 18 A channels in one module means each axis is sized as its own drive — the 400 V 3 AC output is per motor, not summed, and the upstream DC bus has to feed 36 A continuous across both inverters under simultaneous full load without sagging the link. At 400 V class the 18 A figure translates to roughly 7.5 kW per axis in a typical servo duty — the so-what for a controls integrator is that two adjacent axes on the same module share the cooling path and the DC-link capacitor bank, so thermal headroom on one channel is not independent of the other.
Lifecycle read for the buyer
The product record carries a value of mature on this SINAMICS S120 line — mature is Siemens' bracket for established product that is still orderable but no longer at the front of the new-design push, which frames this as a configured-line spare rather than a greenfield selection. The listing is dated 04.01.2021 (Änderungen vorbehalten © Copyright Siemens 2021) — that is the document revision timestamp rather than a production date, and it is the figure that travels with the declaration pack when quality doc control traces the nameplate back to the PO.
Sourcing posture on a mature line
Sourcing on a mature SINAMICS S120 module runs through the same RFQ channel as the rest of the booksize line — the BOM position gets quoted against a lead time and a price-break ladder confirmed at quote time, with no stock count or immediacy promise made here.