Moeller STI 0.06 Control Transformer 400V to 110V 60VA 50-60Hz ±5% Taps

Moeller STI 0.06 Control Transformer 400V to 110V 60VA 50-60Hz ±5% Taps

The Moeller STI 0.06 is a single-phase step-down control transformer designed to convert a 400V AC primary supply to a 110V AC secondary output at up to 60 VA. The primary terminal block includes five positions — 0, -5%, 400V, and +5% — allowing the input voltage to be trimmed to 380V or 420V to accommodate supply variations. The transformer is built on a laminated E-I core and mounts via an integrated DIN rail foot, making it suitable for panel and cabinet installation.

Specifications & What's Included

• Manufacturer: Moeller (Eaton Moeller)
• Model: STI 0.06
• Catalog / Knr: 238989
• Type: Single-phase control transformer
• Primary Voltage: 400V AC
• Primary Current: 0.19 A
• Secondary Voltage: 110V AC
• Secondary Current: 0.55 A
• Power Rating: 60 VA
• Apparent Power (Sn/Sk): 60/130 VA
• Frequency: 50-60 Hz
• Phase: Single phase
• Impedance Voltage: Uk 7.76%
• Insulation Class: Class 105 (A)
• Primary Voltage Taps: 0, -5% (380V), 400V nominal, +5% (420V)
• Mounting: DIN rail / panel mount via integrated bracket
• Standards: VDE0550 ta40B, EN60742 ta40B, EN60947-4-1
• Certifications: UL506, CE, ÖVE, RU
• Includes: Transformer with DIN rail mounting bracket — no additional cables or accessories

Applications

Control transformers like the STI 0.06 are standard components in European industrial machinery and automation panels, where a 400V three-phase supply is present but control circuits — relay coils, solenoids, indicator lights, and PLC I/O — operate at 110V AC. The step-down ratio of 400V to 110V reflects the European industrial control voltage standard (as opposed to the North American 120V standard), and these units are commonly found in machine tool cabinets, conveyor control panels, packaging machinery, and similar factory-floor equipment. The ±5% primary taps allow the transformer to compensate for local supply voltage variations without replacing the unit. At 60 VA, this size is suited for small control circuits — typically a handful of relay coils or a single solenoid valve. Moeller (now part of Eaton's electrical division) produced the STI series as a compact, DIN rail-mountable solution widely used across European OEM machine builders from the 1990s onward.