The Siemens SITAS 4AT3612-8DD40 is a 5 kVA control transformer — the entry point to the 4AT heavy-industrial series, designed for the largest motor control centers, switchgear, and process control installations. Its eleven primary taps (550 V to 208 V) cover every industrial mains voltage worldwide, while the dual 2×115 V secondary provides massive 21.7 A per winding — enough to power the entire control system of a major industrial facility. The 19,000 VA short-time (S6) rating handles the inrush of dozens of large contactors closing simultaneously. Insulation class H (155°C) with a 55°C ambient rating reflects the 4AT series design for the harshest industrial environments — steel mills, foundries, and desert installations where panel temperatures exceed the standard 40°C limit. At approximately 46 kg on a 194 × 169 × 320 mm chassis, this is a floor-standing or large-enclosure component.

Key Features

• 5,000 VA continuous, 19,000 VA S6 — industrial-scale control power
• 11 primary taps (550–208 V) — universal global mains compatibility
• Dual 2×115 V secondary, 21.7 A per winding (43.5 A parallel)
• Insulation class H (155°C) with 55°C ambient rating — extreme environment ready
• 94% efficiency, 50/60 Hz, IP00 open-frame
• Screw/chassis mounting, 194 × 169 × 320 mm, ~46 kg
• UL/CSA recognized, CE, EAC certified

Technical Data

Applications

Heavy industrial and utility-scale control systems: steel mill motor control centers, power plant auxiliary panels, water/wastewater treatment plant MCCs, mining switchgear control circuits, and oil/gas process control buildings. The class H insulation and 55°C ambient rating are essential for installations in un-air-conditioned electrical rooms in hot climates. The 5 kVA rating serves as the single control power source for an entire motor control center lineup.