The Siemens 3SK1230-1AW20 is a SIRIUS safety relay power supply — a DIN-rail-mounted, 24 V DC / 0.6 A output module that powers the logic side of a safety relay or small safety controller. It accepts 110–240 V AC (50/60 Hz) or DC input and delivers a regulated 24 V DC at 0.6 A, with galvanic isolation between input and output and an output that is short-circuit proof. The 22.5 mm width means it takes one standard modular position in the enclosure, and it mounts by screw or snap-on in any orientation.
The 0.6 A output is the continuous rated current at 24 V DC — sized to power the internal bus of a 3SK1 safety relay or a small safety logic module, not for driving field actuators. Power loss is 17 W, which is heat that must be dissipated inside the enclosure; with a 22.5 mm footprint and no forced cooling, keep ambient below 60 °C and respect the 5 mm side spacing to grounded parts for natural convection. The surge voltage resistance of 4 000 V and overvoltage category 3 confirm it's rated for fixed-installation industrial panels where transients from contactor or motor switching are expected.
Integration notes
Screw terminals accept solid wire 1x (20…14 AWG) or 2x (18…16 AWG), and with ferrules 1x (0.5…2.5 mm²) or 2x (0.5…1.0 mm²). Strip length is the standard 8–10 mm for this terminal class. The green LED lights when 24 V output is present — useful during commissioning to confirm the supply is alive before the safety relay logic is energized. Shock resistance of 10g / 11 ms covers most machine-mounted applications but not high-vibration zones near un-damped presses or crushers.