The Siemens SITAS 4AM3842-4TJ10 delivers 160VA of isolated 110V AC control power from a standard 230V AC mains supply, widely used in UK construction site temporary power and railway signaling control panels where reduced low voltage (RLV) is mandatory for personnel safety.

110V Output for Safety-Critical Control Circuits

The 110V secondary complies with BS 7671 reduced low voltage requirements for construction sites and BS EN 50122 for railway signaling applications. The center-tapped 55-0-55V configuration commonly derived from 110V output provides earth fault protection with a 55V maximum touch voltage. With ±5% primary taps (218/230/242V), the transformer adapts to site supply voltage variations while maintaining stable 110V output.

490VA Short-Time Overload Capacity

The S6 short-time duty rating of 490VA — over three times the continuous 160VA rating — handles motor contactor pull-in currents and control circuit startup surges without voltage sag. This prevents contactor dropout during motor starting sequences, a critical requirement in machine tool control panels where control voltage integrity must be maintained during all operating conditions.