SIEMENS 6SL3120-1TE31-3AA3 Retrofit-Compatible Single Motor Module

SIEMENS 6SL3120-1TE31-3AA3 Retrofit-Compatible Single Motor Module for Legacy System Modernization

The SIEMENS 6SL3120-1TE31-3AA3 is a booksize-format Single Motor Module belonging to the SINAMICS S120 drive system family. Rated at 132 kW output power with a DC link voltage of 600 V, this module is engineered for high-dynamic servo and vector control applications across a wide range of industrial sectors including automotive manufacturing, paper and printing machinery, metal processing lines, and heavy-duty conveyor systems. As legacy SINAMICS S120 components reach end-of-life or become increasingly difficult to source through standard distribution channels, the 6SL3120-1TE31-3AA3 has become a critical retrofit and replacement unit for engineers tasked with keeping aging production lines operational without committing to a full drive system overhaul.

When planning a retrofit around the 6SL3120-1TE31-3AA3, the first step is always a thorough audit of the existing DC bus architecture. The module connects to the shared DC link rail via the booksize chassis backplane, and engineers must confirm that the upstream Active Line Module or Basic Line Module — such as the 6SL3130-7TE31-6AA3 or 6SL3130-6AE21-0AB0 — can supply sufficient DC bus capacity to support the 6SL3120-1TE31-3AA3 alongside any other motor modules already installed in the same cabinet. Undersized line modules are one of the most common causes of nuisance trips during commissioning after a module swap.

Terminal and connector compatibility is the next critical checkpoint. The 6SL3120-1TE31-3AA3 uses the standard SINAMICS S120 booksize motor output terminals, and in most cases the existing motor cable and shield termination can be reused without modification. However, engineers should verify the motor cable cross-section against the module’s rated output current and confirm that the PE bonding conductor meets local installation standards. If the legacy installation used an older booksize variant with a different terminal pitch or a different shield clamp design, a short cable adapter section may be required to maintain a clean, low-impedance motor connection.

Upgrade Compatibility Table

Retrofit Planning for Existing Automation Systems

A successful retrofit using the 6SL3120-1TE31-3AA3 requires careful coordination across multiple system layers. Starting at the power supply level, the existing Active Line Module must be verified for adequate kW headroom. In many legacy S120 cabinets, the line module was sized conservatively at initial commissioning, and adding a higher-rated motor module without recalculating the DC bus load can result in overcurrent faults on the line module. If the existing line module is marginal, a parallel upgrade to a higher-rated 6SL3130-series Active Line Module should be planned concurrently.

At the backplane level, the 6SL3120-1TE31-3AA3 slots into the standard SINAMICS S120 booksize chassis. Engineers should inspect the backplane connector pins for corrosion or mechanical damage before insertion, particularly in installations that have been in service for more than ten years. The DRIVE-CLiQ topology must also be re-mapped after the module swap: the CU320-2 Control Unit automatically detects the new module during power-up, but the drive object assignment in the project file must be updated to reflect the new component serial number. Failure to update the DRIVE-CLiQ topology in the STARTER or Startdrive project will result in a topology mismatch fault (F01375) that prevents the drive from enabling.

For sites running PROFIBUS DP as the fieldbus backbone, the CU320-2 DP control unit handles all PLC-to-drive communication, and the 6SL3120-1TE31-3AA3 itself does not require any additional PROFIBUS configuration — the motor module is addressed as a drive object within the control unit’s parameter set. Sites that have already migrated to PROFINET should use the CU320-2 PN variant and verify that the PLC’s GSDML device description file matches the installed firmware version on the control unit. In mixed installations where some axes remain on PROFIBUS while others have been migrated to PROFINET, a CBE20 Communication Board Extension can be fitted to the CU320-2 to support both protocols simultaneously.

I/O expansion requirements should also be reviewed during retrofit planning. If the legacy installation relied on a TM31 Terminal Module for analog speed references or digital enable signals, the existing TM31 wiring can typically be retained without modification. Similarly, if encoder feedback is provided via a SMC30 Sensor Module Cabinet-Mounted or an SME20 Sensor Module External, these modules remain fully compatible with the 6SL3120-1TE31-3AA3 and do not need to be replaced as part of the motor module swap. The encoder cable shield should be inspected and re-terminated if there is any evidence of intermittent feedback faults in the maintenance history.

HMI integration is another area that requires attention during the retrofit. If the machine uses a SIMATIC HMI panel — such as a TP700 Comfort or TP1200 Comfort — connected to the drive system via PROFINET or PROFIBUS, the HMI screen objects that display drive status, speed feedback, and fault codes should be tested after the module replacement to confirm that the tag addresses remain valid. In some cases, a firmware update on the CU320-2 may change the parameter numbering for certain drive objects, requiring corresponding updates to the HMI project.

Downtime Control During System Migration

Minimizing production downtime is the primary commercial driver for most retrofit projects involving the 6SL3120-1TE31-3AA3. The recommended approach is to pre-commission the replacement module on a test bench before the scheduled maintenance window. Using a laptop running SINAMICS Startdrive and a DRIVE-CLiQ USB adapter, the module’s firmware can be updated and the basic drive parameters can be loaded from the existing project backup before the module is installed in the production cabinet. This pre-commissioning step typically reduces the in-cabinet commissioning time to less than two hours, compared to four to six hours for a cold-start commissioning from scratch.

Before powering down the existing system, a full parameter backup should be exported from the CU320-2 using the STARTER project upload function or the Startdrive upload workflow. This backup serves as both a reference document and a recovery file in the event that the new module requires parameter adjustments during commissioning. The backup should be stored in at least two locations — on the commissioning engineer’s laptop and on a USB memory stick kept in the control cabinet — to protect against data loss.

During the physical swap, the DC bus capacitors in the existing motor module must be fully discharged before the module is removed from the chassis. The standard discharge time after mains isolation is five minutes, but engineers should always verify with a calibrated DC voltmeter before touching any DC bus conductors. Once the 6SL3120-1TE31-3AA3 is installed and the DRIVE-CLiQ and motor cables are reconnected, the system can be powered up in a controlled sequence: line module first, then control unit, then motor modules. The CU320-2 will perform an automatic component recognition cycle, after which the engineer can confirm the topology and enable the drive for a no-load test run before reconnecting the mechanical load.

All units supplied by NINERMAS are subject to a pre-shipment functional test that verifies DC bus charging, DRIVE-CLiQ communication, and output stage integrity. A 12-month warranty is provided from the date of shipment, covering manufacturing defects and component failures under normal operating conditions.

Retrofit Support FAQ

Q1: Is the 6SL3120-1TE31-3AA3 a direct drop-in replacement for earlier SINAMICS S120 booksize motor modules?
A: In most cases, yes. The 6SL3120-1TE31-3AA3 is mechanically and electrically compatible with the standard SINAMICS S120 booksize chassis. However, engineers should verify that the firmware version on the CU320-2 Control Unit supports the replacement module, and that the DRIVE-CLiQ topology is updated in the commissioning project after the swap.

Q2: What commissioning steps are required after installing the 6SL3120-1TE31-3AA3?
A: After physical installation, power up the system and allow the CU320-2 to complete its automatic component recognition. Confirm the DRIVE-CLiQ topology in STARTER or Startdrive, load the parameter backup from the previous module, and perform a no-load test run to verify speed control and current regulation before reconnecting the mechanical load. Check encoder feedback signals and HMI tag validity before returning the machine to production.

Q3: Can the existing motor cable and encoder wiring be reused?
A: In most retrofit scenarios, yes. The motor output terminals on the 6SL3120-1TE31-3AA3 are compatible with standard SINAMICS S120 booksize motor cables. Encoder feedback via SMC30 or SME20 sensor modules is also fully compatible. Engineers should inspect cable insulation and shield terminations and replace any sections showing signs of wear or damage.

Q4: What warranty and stock availability does NINERMAS offer for the 6SL3120-1TE31-3AA3?
A: NINERMAS maintains stock of the 6SL3120-1TE31-3AA3 and can typically ship within 3–5 business days. All units are pre-tested before shipment and covered by a 12-month warranty from the date of delivery. For urgent retrofit requirements, expedited shipping options are available. Contact our team at sale@ninermas.com or +0086 187 5021 5667 for current stock levels and lead times.