The Siemens SITAS 4AM4342-5AN00 is a 315VA safety isolating control transformer converting a 400V primary supply to 24V at 13.1A. It is the higher-power alternative to the 250VA 4AM4042-5AN00, providing 26% more continuous capacity for European industrial panels where 24VDC control circuits are derived from the 400V three-phase mains via a transformer-rectifier combination.

Electrical Performance

Built on the EI 105/60 core at approximately 90% efficiency, the 1,120VA short-time (S6) rating — 3.6x the 315VA continuous rating — comfortably handles contactor and solenoid inrush. The 6.08% short-circuit voltage ensures stable output regulation. Primary taps at 380V, 400V, and 420V (+-5%) accommodate site voltage variation.

24V System Capacity

At 13.1A secondary current, this transformer supports large-scale 24V control systems: multiple PLC racks, safety relay chains, distributed I/O modules, HMI panels, and signal conditioning devices — all from a single transformer. Combined with a three-phase rectifier, it forms the core of a robust 24VDC power supply for machine and process automation.

Construction & Certifications

IP00 open-frame, 107x111x120mm, ~4.6kg, screw mounting. Certified to EN 61558-2-2 and EN 61558-2-6 with CE, cRUus, and EAC. Class B insulation, 40 C ambient.