SIEMENS 6SL3351-1AE37-5BA1 Service-Ready Spare Part

SIEMENS 6SL3351-1AE37-5BA1 Service-Ready Spare Part for Industrial Maintenance

The SIEMENS 6SL3351-1AE37-5BA1 is a ruggedized Power Block Module engineered for demanding industrial environments within the SINAMICS S120 drive system platform. For maintenance engineers managing high-availability production lines, motion control systems, or process automation infrastructure, this module represents a critical spare part that directly determines uptime and recovery speed when a drive fault occurs. Sourced as an original SIEMENS component, the 6SL3351-1AE37-5BA1 is stocked, tested, and shipped with a 12-month warranty to support your spare parts inventory strategy and minimize unplanned downtime risk.

Whether you are responding to an emergency shutdown, executing a planned annual overhaul, or building a preventive maintenance spare parts kit for your control cabinet, having the 6SL3351-1AE37-5BA1 on hand eliminates the lead time risk that often extends production stoppages from hours into days. Procurement engineers sourcing for multi-site facilities or MRO inventory programs will find this module available for long-term supply agreements, with consistent quality verification and pre-shipment functional testing included as standard.

Spare Maintenance Table

Maintenance Planning for Continuous Operation

When replacing the 6SL3351-1AE37-5BA1 Power Block Module in a SINAMICS S120 drive system, a thorough site inspection of the surrounding electrical circuit is essential to prevent repeat failures and ensure a clean restoration of drive operation. Maintenance engineers should begin by verifying the condition of the DC link capacitors and the associated DC bus fusing, as power block failures are frequently preceded or caused by overvoltage transients or fuse degradation upstream.

The SINAMICS S120 Control Unit — typically a CU320-2 DP or CU320-2 PN — should be inspected for active fault codes and firmware compatibility with the replacement module. The DRIVE-CLiQ communication cable connecting the Control Unit to the Motor Module and Power Module must be checked for continuity and connector integrity, as signal degradation on this bus can cause intermittent faults that are misdiagnosed as power block failures. Similarly, the Sensor Module Cabinet-Mounted (SMC) units used for encoder feedback should be verified for correct operation after the power block swap.

On the power supply side, the SINAMICS S120 Active Line Module (ALM) or Basic Line Module (BLM) feeding the DC bus should be inspected for output voltage stability and any signs of thermal stress. Line reactors and sine-wave filters installed upstream of the drive system should also be checked for winding resistance and insulation integrity. If the system uses a Braking Module and braking resistor for regenerative energy dissipation, these components should be tested to confirm they are not contributing to DC bus overvoltage conditions that may have caused the original power block failure.

For cabinet-level maintenance, inspect the 24 VDC SITOP power supply units providing logic power to the control rack, as voltage sags or ripple on the 24 V rail can cause erratic behavior in the CU320 and associated I/O modules. Terminal blocks, particularly those on the motor output terminals and PE bonding conductors, should be re-torqued to specification. If the drive system interfaces with a SIMATIC S7-300 or S7-1500 PLC via PROFIBUS DP or PROFINET, verify that the network topology and device addressing remain intact after the module replacement. Any SIMATIC HMI panels connected to the system should be checked for alarm history that may reveal pre-fault conditions not captured in the drive’s own fault buffer.

Building a structured spare parts kit around the 6SL3351-1AE37-5BA1 for a SINAMICS S120 installation should include at minimum: a spare CU320-2 Control Unit, one set of DRIVE-CLiQ cables in the relevant lengths, a replacement SITOP 24 VDC PSU, spare DC bus fuses rated for the system’s short-circuit current, and a set of terminal block connectors for the motor output and feedback wiring. For facilities operating multiple S120 chassis drives, maintaining one complete spare power block per drive rating tier significantly reduces mean time to repair (MTTR) during unplanned outages.

Site Replacement Workflow

Before beginning the physical replacement of the 6SL3351-1AE37-5BA1, isolate the drive system from the main supply using the upstream circuit breaker or disconnector and verify zero energy state with a calibrated voltage tester on the DC bus terminals — SINAMICS S120 chassis drives retain dangerous DC bus voltage for several minutes after power removal. Lock out and tag out (LOTO) procedures must be followed in accordance with site safety regulations.

Once safe isolation is confirmed, document the existing wiring configuration with photographs before disconnecting the motor output cables (U2, V2, W2), the DC bus busbars, and the DRIVE-CLiQ connector. Remove the faulty 6SL3351-1AE37-5BA1 from the cabinet mounting rails, noting the torque values for all busbar bolts as specified in the SINAMICS S120 hardware installation manual. Install the replacement module, reconnect all conductors in reverse order, and verify that the DRIVE-CLiQ topology is correctly recognized by the Control Unit upon power-up.

After energization, clear any residual fault codes from the CU320 and perform a short no-load test run before reconnecting the mechanical load. Confirm that motor current, DC bus voltage, and thermal readings are within normal operating parameters. Update the maintenance log with the replacement date, new module serial number, and any observations noted during the procedure. For systems where the 6SL3351-1AE37-5BA1 is replacing an older or discontinued variant, verify that the firmware version on the Control Unit supports the new module’s feature set, and perform a firmware update if required to maintain full system compatibility.

Spare Parts Support FAQ

Q1: Is the 6SL3351-1AE37-5BA1 compatible with all SINAMICS S120 chassis configurations?
The 6SL3351-1AE37-5BA1 is designed for the SINAMICS S120 Chassis format and is compatible with standard S120 system configurations using the corresponding line and motor modules. Compatibility should always be verified against the existing system’s power rating, DC bus voltage, and Control Unit firmware version before installation. Our technical team can assist with compatibility confirmation prior to order.

Q2: What pre-shipment testing is performed on this module?
Every 6SL3351-1AE37-5BA1 unit undergoes functional and electrical verification before dispatch, including insulation resistance checks, DC bus capacitor integrity assessment, and DRIVE-CLiQ interface validation where applicable. A test report is available upon request. All units are shipped with a 12-month warranty covering manufacturing defects and functional failures under normal operating conditions.

Q3: Can you support long-term or blanket purchase orders for this spare part?
Yes. NINERMAS supports long-term supply agreements for MRO and spare parts inventory programs. For facilities managing multiple SINAMICS S120 installations or requiring guaranteed stock availability for critical production lines, we offer scheduled delivery programs and priority allocation. Contact our sales team to discuss volume pricing and supply continuity arrangements.

Q4: What is the recommended inventory strategy for the 6SL3351-1AE37-5BA1?
For production environments where SINAMICS S120 drives are critical to output, maintaining at least one spare 6SL3351-1AE37-5BA1 per drive rating tier on-site is recommended. For multi-drive installations or facilities with extended supplier lead times, a minimum stock of two units per site is advisable. Spare parts should be stored in a dry, temperature-controlled environment within the original packaging to preserve component integrity and warranty validity.