The SITAS 4AM3242-5AT10-0FA0 provides safety-isolated 230VAC control power from a 400V mains feeder, rated at 63VA continuous with 190VA short-time surge capability. For panels built to European IEC standards where the incoming supply is 400V three-phase and the control circuit operates at 230V single-phase, this transformer bridges the voltage gap while providing the mandatory galvanic separation between line and control circuits required by EN 60204-1.

Why 230V Control Circuits

While 24V has become the dominant control voltage in modern automation panels, 230V control circuits remain common in machinery built before widespread 24V adoption, in power distribution switchgear where control power is derived directly from the mains, and in applications where the longer cable runs of large installations would suffer unacceptable voltage drop at 24V. The 4AM3242-5AT10-0FA0 delivers 0.27A at 230V — sufficient for multiple contactor coils, timing relays, and panel indicators operating at line voltage.

Construction and Safety

Built on the EI 84/28 laminated core platform shared across the 63VA SITAS range, the transformer uses the ±5% tapped primary (380/400/420V) to match site supply voltage. The II0 vector group with zero shielding winding provides basic safety isolation per EN 61558-2-6. No earth reference exists on the secondary unless the installer intentionally grounds one leg — standard practice is to ground one side of the 230V control circuit for safety. Operating frequency is 50/60Hz, thermal class B (40°C ambient max), and the enclosure rating is IP00 for in-cabinet mounting only.

Key Decision Parameters

For 24V secondary control circuits from the same 400V primary, the 4AM3242-5AN00-0EA0 provides 2.63A at 24V.