The Siemens SITAS 4AM4042-4TN00-0EA1 is a 250VA single-phase control and safety isolating transformer converting 230V primary to 24V secondary at 10.4A. The 0EA1 variant features cage-clamp terminals for tool-free, vibration-resistant wiring — a practical advantage for high-volume panel builders.

Electrical Performance

With an 850VA short-time (S6) rating, it comfortably handles contactor, relay, and solenoid inrush currents. The 89%-efficient EI 96/58 laminated core keeps heat dissipation low. Primary taps at 218V, 230V, and 242V (±5%) accommodate supply voltage variation.

Safety & Standards

The 24V secondary provides SELV-level output for safe control circuit operation. Certified to EN 61558-2-2 and EN 61558-2-6 as both a control and safety isolating transformer, with CE, cRUus, and EAC approvals. Class B insulation (IEC 60085) rated for 40°C ambient.

Installation

IP00 open-frame design, 98×106×118mm, 4.6kg. Mounts via screws or 35mm DIN rail. Cage-clamp terminals accept solid or stranded conductors without ferrules, speeding installation while maintaining secure, gas-tight connections.