The Siemens 6SL3210-1PE21-1UL0 is a SINAMICS G120 Power Module PM240-2 intended for robust, cabinet-mounted variable-speed drive systems in standard industrial environments. In the SINAMICS G120 architecture, the Power Module is the “power stage” that handles energy conversion and motor output, while a compatible Control Unit provides control logic, parameterization, and communications. This modular design is popular with OEMs and panel builders because it allows you to standardize the power hardware and tailor control features to each machine or customer requirement.
This specific module is designed for 3-phase 380 to 480 V AC mains with 47 to 63 Hz line frequency tolerance, making it suitable for many global factory power distributions. For users who need one hardware platform to cover both “general machinery” and “fan/pump-like” loads, Siemens defines two operating profiles: High Overload (HO) and Low Overload (LO). In LO mode the module is rated 4.0 kW at IEC 400 V, while in HO mode it is rated 3.0 kW at IEC 400 V. This dual-profile concept is not cosmetic—it directly affects thermal design, acceleration capability, and the drive’s allowable overload behavior.
Where this Power Module shines is in the messy reality of production lines: frequent start/stop, uneven loads, and the need for consistent machine behavior across shifts. The datasheet lists overload capability in a way that maps to real cycles: in LO, it supports 110% rated output current for 57 seconds and 150% for 3 seconds (cycle time 300 seconds). In HO, it supports 150% for 57 seconds and 200% for 3 seconds (cycle time 300 seconds). Translation: LO is typically chosen when continuous duty dominates (often fans and pumps), while HO is chosen when you need stronger short-term torque and harsher acceleration/braking cycles.
The electrical and thermal design details matter just as much as the headline kW rating. Siemens specifies internal air cooling with a cooling air requirement of 0.009 m³/s, and a reference installation altitude of 1000 m. Ambient limits are clearly defined: LO operation -5 to +40 °C, HO operation -5 to +50 °C, and 95% relative humidity with condensation not permitted. Those constraints are exactly what separates a drive cabinet that runs for years from one that slowly cooks itself and becomes a “random trip generator.”
From a commissioning and acoustic standpoint, the module specifies 4 kHz pulse frequency and a 72 dB sound pressure level (1 m) as well as typical electrical behavior values like power factor λ 0.85, cos φ 0.95, and efficiency η 0.97 (under the stated conditions). For many projects, these numbers help justify cabinet placement, ventilation, and expectations about heat and noise. Siemens also provides a quantified power loss of 0.11 kW, which is extremely useful for cabinet thermal budgeting.
Mechanically, the 6SL3210-1PE21-1UL0 is an IP20 / UL open type module intended for installation inside an enclosure. It is frame size FSB with dimensions approximately 292 mm (height) × 100 mm (width) × 165 mm (depth) and a net weight of 2.90 kg (without the integrated filter variant). Cabling is designed for industrial practicality: it uses plug-in screw terminals, supports 1.50 to 6.00 mm² (AWG 16 to AWG 10) conductor cross-sections on both line and motor sides, and specifies maximum motor cable lengths of 100 m unshielded and 50 m shielded.
For efficiency and regulatory discussions, the datasheet references losses evaluation and assigns an IE2 efficiency class (converter losses standard reference). Compliance listings include UL, cUL, CE, RCM (C-Tick), and SEMI F47, which is helpful when the drive system must pass acceptance in multinational plants or semiconductor-adjacent environments.
Core Technical Data (Summary Table)
| Item | Specification |
|---|---|
| Product | SINAMICS G120 Power Module PM240-2 |
| Order Number | 6SL3210-1PE21-1UL0 |
| Supply (Input) | 3 AC 380…480 V ±10%, 47…63 Hz |
| Rated Power | LO: 4.00 kW (IEC 400 V) / HO: 3.00 kW (IEC 400 V) |
| Rated Input Current | LO: 13.30 A / HO: 11.60 A |
| Rated Output Current | LO: 10.20 A / HO: 7.70 A |
| Max Output Current | 15.40 A |
| Output Rated Voltage | 400 V |
| Output Frequency | Vector control: 0…200 Hz; V/f control: 0…550 Hz |
| Pulse Frequency | 4 kHz |
| Cooling | Internal air cooling; cooling air requirement 0.009 m³/s |
| Ambient Limits | LO -5…40 °C; HO -5…50 °C; 95% RH non-condensing |
| Protection | IP20 / UL open type |
| Mechanical | Frame size FSB; 292 × 100 × 165 mm; net weight 2.90 kg |
| Connections | Plug-in screw terminals; 1.50…6.00 mm² (AWG 16…10) |
| Motor Cable Length | 100 m unshielded / 50 m shielded |
| Losses / Efficiency | Power loss 0.11 kW; efficiency η 0.97; IE2 class (losses evaluation reference) |
| Standards | UL, cUL, CE, RCM, SEMI F47 |
What Makes This Model Useful in Real Projects
1) A practical “4 kW class” module with two personalities
The same hardware can be used either as a 4.0 kW LO module for smoother continuous duty or as a 3.0 kW HO module when the cycle includes heavier torque bursts and harsher acceleration ramps. This reduces SKU fragmentation in your drive cabinet BOM (bill of materials) and makes spares management cleaner.
2) Clear thermal budgeting for enclosure design
The datasheet gives you direct inputs for heat and airflow planning: 0.11 kW power loss and 0.009 m³/s cooling air requirement. That’s the kind of data you can actually use to size fans, place ducting, and predict cabinet temperature rise.
3) Defined wiring limits and maintainable terminals
With plug-in screw terminals and specified conductor sizing, the hardware is designed for predictable installation quality. Cable length limits (100 m unshielded / 50 m shielded) help prevent late-stage commissioning surprises like overvoltage reflections, EMC issues, and unstable control behavior.
Application Fit (Engineering-Oriented Table)
| Application Type | Why PM240-2 6SL3210-1PE21-1UL0 Fits | Typical Profile Choice |
|---|---|---|
| Pumps and fans | Continuous duty, energy optimization, wide speed range | LO (4.0 kW) |
| Conveyors | Start/stop cycles, load variation, torque bursts | HO (3.0 kW) when starts are heavy |
| Mixers / agitators | Controlled ramps reduce mechanical shock | Depends on inertia and cycle aggressiveness |
| General machinery | Standardized cabinet builds and repeatable service practices | LO or HO based on duty cycle |
Installation Notes That Save Time Later
| Topic | Practical Advice | Datasheet Anchor |
|---|---|---|
| Cabinet ventilation | Treat airflow as a design requirement, not an afterthought | Cooling air requirement and ambient limits |
| Environmental control | Avoid condensation; humidity spec assumes non-condensing conditions | 95% RH, condensation not permitted |
| Cable planning | Keep motor cable within specified limits; choose shielding intentionally | 100 m unshielded / 50 m shielded |
| Load profiling | Pick LO vs HO based on cycle time, acceleration demands, and overload needs | Overload capability definitions |
Conclusion
The Siemens 6SL3210-1PE21-1UL0 is a cabinet-mounted SINAMICS G120 PM240-2 Power Module built for 380–480 V three-phase industrial environments, offering a highly usable balance of 4.0 kW LO capability and 3.0 kW HO performance with clearly defined overload behavior, thermal requirements, wiring limits, and mechanical integration data. If your goal is a drive cabinet that is easy to build, predictable to commission, and stable across real-world cycles, this model is a strong, engineering-friendly choice in the PM240-2 family.
