Power module with integrated braking chopper
The Siemens 6SL3211-1PB21-0UL0 is a SINAMICS Power Module PM240-2, unfiltered, with an integrated braking chopper. It operates on a 200-240 V supply, single- or three-phase, 47-63 Hz. The key selection decision is the overload duty: at high overload (HO) it delivers 1.5 kW with 200% current for 3 seconds and 150% for 57 seconds, within a -10 to +50 °C ambient. For low overload (LO) it delivers 2.2 kW at 150% for 3 seconds and 110% for 57 seconds, but the ambient limit drops to +40 °C. This means the HO rating governs for cyclic loads like conveyors or pumps that need short torque bursts; the LO rating applies for steady-running fans or compressors where the thermal headroom is tighter.
Mounting and integration
The module is FSB frame size, 345 x 154 x 171 mm (HxWxD), with IP20 degree of protection — suitable for enclosure mounting in a clean, dry control cabinet. It requires a separate Control Unit (CU) and operating unit; the power module itself is released as of CU firmware version V4.6. The integrated braking chopper handles DC-link energy from decelerating loads, so no external braking resistor is needed for moderate duty cycles.