Single-phase and Three-phase Autotransformers

All our autotransformers are made to order, with tensions, primary and secondary numbers, connections, dimensions, implementations and options made at the customer's request.

• Single-phase autotransformers in accordance with standard IEC/EN 61558-2-13
• Three-phase autotransformers in accordance with standard IEC/EN 61558-2-13

Technical Specifications

• Service: continuous
• Frequency: 50...60 Hz
• Ambient temperature: 40°C
• Thermal insulation class (depending on power): F / H
• Electrical protection class: I
• Degree of protection: IP00
• Magnetic core: low core loss
• Coating: covered in class H varnish

Some examples of possible uses

• Thermal protection, thermistor
• Magnetic core with grain-oriented (G.O.) steel
• Connection with front clamps, on DIN rail
• For single-phase: fixing with frames, angular, also compliant with DIN 41307 standards
• For three-phase: brackets for vertical, horizontal fixing
• Painted steel container, stainless steel
• Lifting eyebolt

The autotransformers are transformers with only one coil working as primary and secondary, therefore there is no galvanic isolation between the two.
These products are convenient from an economic point of view when used in place of a transformer of equal power as the difference in tension between the input and output is lower.

In addition, autotransformers offer higher yields, reduced losses, lower short-circuit voltages and lower voltage variations from vacuum to load.

To evaluate its effectiveness, the sizing power must be calculated using the following formula:

Pd = [(Vmax-Vmin) / Vmax] x PV

Where:

• Pd = sizing power
• Pn = nominal power
• Vmin = minimum operation voltage
• Vmax = maximum operation voltage