The Siemens SITAS 4AM3842-4TN00 is a 160VA safety isolating transformer that steps 230V AC mains down to 24V AC SELV (Safety Extra-Low Voltage) for machine control circuits, PLC I/O interfaces, and industrial safety systems. Compliant with EN 61558-2-6 safety isolating transformer standards, it provides galvanic isolation between primary and secondary circuits, protecting personnel and sensitive control electronics from mains-borne faults.

24V SELV Output for Machine Safety Circuits

At 160VA continuous rating, the transformer delivers 6.67A at 24V AC — sufficient for powering multiple contactor coils, relay logic banks, solenoid valves, and PLC input modules simultaneously. The 24V SELV voltage level is universally adopted in machine building as it eliminates electric shock risk while remaining high enough to drive inductive loads reliably. Primary voltage taps at 218/230/242V compensate for site supply variations.

490VA Inrush Capacity for Inductive Loads

Control circuit contactors and solenoids draw 3-5× their holding current during pull-in. The 490VA S6 short-time rating provides the momentary power needed to seat multiple contactors simultaneously without voltage sag — preventing nuisance dropout in safety-critical machine control sequences.