Siemens 6SL3210-1SE21-8UA0 PM340 Power Module for SINAMICS S120 Drives
Product Overview
The Siemens 6SL3210-1SE21-8UA0 is a Power Module (PM340) belonging to the SINAMICS S120 drive family. This blocksize module serves as the power stage for single-axis AC drives, converting three-phase 380-480V AC to a variable-voltage, variable-frequency output for induction or synchronous motors. It is rated at 18 A nominal output, corresponding to 7.5 kW (10 HP) typical motor power. The PM340 is designed to be combined with a Control Unit (CU310-2 or CU320-2) to form a complete drive system.
Key Specifications
Model: 6SL3210-1SE21-8UA0
Product Type: Power Module PM340 (blocksize)
Frame Size: FSC (Blocksize)
Input Voltage: 3-phase 380-480 VAC, 50/60 Hz
Output Current (rated): 18 A (for 7.5 kW motor)
Output Current (base load): 15 A (at 400V, for high overload)
Short-term Overload: 150% for 60s, 200% for 3s
Efficiency: ≈ 98% at rated power
Protection: Overcurrent, overvoltage, undervoltage, overtemperature, short circuit
Cooling: Internal air cooling (integrated fan)
Mounting: DIN rail or screw mounting
Dimensions (WxHxD): 100 × 305 × 235 mm (approx.)
Weight: 5.0 kg
Modular Drive Architecture
The PM340 is part of the SINAMICS S120 modular system, which separates the control intelligence from the power stage. The power module connects to a Control Unit via a DRIVE-CLiQ interface (using an adapter cable). The Control Unit handles all closed-loop control (vector, servo, V/f) and communication (PROFINET, PROFIBUS). This design allows the same power module to be used with different control units based on the application’s complexity.
Short-Circuit and Overload Capability
The PM340 is designed for high dynamic performance. It can deliver 150% of its rated current for 60 seconds and 200% for 3 seconds, making it suitable for applications with intermittent high torque demand, such as extruders, punch presses, and heavy-duty conveyors. The internal IGBTs are sized accordingly, and the module includes a built-in braking chopper for use with external braking resistors (optional).
Integration and Installation
The blocksize format allows direct mounting in control cabinets without a separate backplane. The module includes terminals for mains supply (L1, L2, L3), motor output (U, V, W), DC link connection (for common DC bus when using multiple modules), and control power (24V via the Control Unit or external supply). The internal fan ensures forced air cooling; proper clearance (100 mm above/below) is required for ventilation.
Applications
Single-axis servo drives for packaging machines
Spindle drives for CNC machine tools
Main drives for extruders and mixers
Conveyor and hoist drives in material handling
Diagnostic and Status LEDs
The PM340 features an LED status indicator on the front panel: green (ready), yellow (operation), and red (fault). Detailed fault information is available via the connected Control Unit’s display or commissioning software (STARTER or SINAMICS Startdrive).
Conclusion
The Siemens 6SL3210-1SE21-8UA0 PM340 power module provides a compact, high-performance power stage for SINAMICS S120 drive systems. Its robust overload capability and modular design make it a core component for modern motion control applications.
