Siemens | SINAMICS S120 booksize Single Motor Module
Siemens 6SL3121-1TE21-8AA3 SINAMICS S120 18 A Single Motor Module
An 18 A external-air-cooled booksize power module identified by the AA3 hardware suffix and its documented AA4 successor.
ManufacturerSiemens
Model6SL3121-1TE21-8AA3
LifecycleCancelled product with successor
01
Key Information
Siemens 6SL3121-1TE21-8AA3 is a SINAMICS S120 Single Motor Module with a 600 V DC input class, a 400 V three-phase motor output and an 18 A rated output current. It uses external air cooling, includes a DRIVE-CLiQ cable and supports optimized pulse patterns together with extended Safety Integrated functions. Siemens identifies 6SL3121-1TE21-8AA4 as the successor, so the complete suffix and project compatibility must be evaluated before replacement.
Identification CheckVerify the complete article number, suffix, terminal or cooling arrangement, controller project and field connections before selection.
02
Functions
Core Functions
- Converts the SINAMICS DC-link supply into one controlled three-phase motor output.
- Provides an 18 A rated power stage for a single motor axis.
- Uses external air cooling to transfer module losses outside the cabinet airflow path.
- Communicates within the drive system through DRIVE-CLiQ.
- Supports the documented optimized pulse patterns.
- Works with the extended Safety Integrated feature set of the associated SINAMICS architecture.
Product Identity
- Manufacturer: Siemens
- Model: 6SL3121-1TE21-8AA3
- Product Type: SINAMICS S120 booksize Single Motor Module
- Lifecycle: Cancelled product with successor
03
Specifications
| Manufacturer | Siemens |
|---|---|
| Order Number | 6SL3121-1TE21-8AA3 |
| Product Family | SINAMICS S120 |
| Module Type | Booksize Single Motor Module |
| DC Input Class | 600 V DC |
| Motor Output | 400 V, 3 AC |
| Rated Output Current | 18 A |
| Cooling Method | External air cooling |
| Axis Count | 1 |
| Communication | DRIVE-CLiQ cable included |
| Lifecycle | Cancelled |
| Successor | 6SL3121-1TE21-8AA4 |
04
Installation
- Match the complete order number, rated current, booksize mounting format and external-cooling arrangement.
- Inspect the external airflow path and keep the specified cabinet opening unobstructed.
- Reproduce the DC-link, motor, protective-earth and DRIVE-CLiQ connections from the approved drive design.
- Restore motor, encoder and safety parameters from the validated SINAMICS project.
- Complete electrical, rotation-direction and safety-function checks before enabling production motion.
05
Lifecycle
- Siemens lists the AA3 version as cancelled and identifies AA4 as its successor.
- Successor status does not by itself confirm a drop-in exchange; hardware, firmware, option and project dependencies must be checked.
- The exact AA3 suffix remains important when maintaining an existing spare-parts baseline.
- Document connector positions, motor data, safety settings and cooling details before removal.
- For a planned migration, validate the AA4 successor in the complete drive topology rather than only comparing the 18 A current rating.
