The Siemens 3RF3050-1AA04 is a 1-pole SIRIUS 3RF30 solid-state relay in the 45 mm width, rated for 50 A continuous load current across a 48-460 VAC supply, switched by a 24 VDC control signal via screw terminals. This is a zero-crossing or random-fire SSR depending on the internal circuit variant — the 3RF30 family handles resistive and lightly inductive loads in industrial heating, lighting, and motor control circuits where silent, wear-free switching is required.
Screw terminals accept 0.5–16 mm² conductors; torque to 2.0–2.5 Nm depending on wire gauge. The 50 A continuous rating assumes the relay is mounted with adequate ventilation — derate by 0.5 A per °C above 40 °C ambient. For dense panel layouts, leave a 10 mm air gap above and below the housing for natural convection. Control-side 24 VDC draws approximately 10–15 mA at nominal voltage. A free-wheeling diode across the DC coil is not required internally but is recommended if the control signal is switched by a PLC transistor output to suppress back-EMF during turn-off.