The Siemens 6ES7928-3AA20-4AA0 is a relay for the TPRO product family, designed to switch 230 V AC loads from a 24 V DC control signal. It is a panel-mount relay typically used in industrial control cabinets for isolating or amplifying digital outputs from a PLC or controller to field devices such as contactors, solenoid valves, or indicator lamps. The 24 V DC coil voltage matches standard industrial control voltages, so it can be driven directly by a PLC digital output module or a 24 V DC power supply without an intermediate interface. The 230 V AC output rating covers single-phase loads common in European and Asian industrial installations.
RoHS compliant since 26 September 2014, and REACH Article 33 applies due to lead content above 0.1% (CAS 7439-92-1). Packaging dimensions are 22.5 x 15.00 x 1.00 cm, suitable for standard DIN-rail enclosures or panel layout. The part is not field-serviceable; replacement is the standard approach for failure.