Product Description


ESS Series

Variable Transformer

DIN rail, PRI 230 Vac, SEC 0 - 250 Vac, 0.8 - 20 A


  • Rotary knobs and scales optionally available

  • 4-point flange mounting

  • Self-cleaning of the exposed contact tracks

  • Stepless adjustment of the AC voltage from zero to the maximum value



Autotransformers are the efficient and ideal solution for minor voltage adjustments. Compact designs can be provided depending on the voltage difference. Autotransformers feature lower losses compared with isolating transformers with the same power rating. The transformers without galvanic isolation also feature inverse operation. BLOCK's standard range features power outputs of between 150 VA and 250,000 VA

  • Efficient solution for minor voltage adjustments
  • Inverse operation possible
  • Power output: 250 VA to 250,000 VA


Variable auto transformer for continuous adjustment of AC voltages or currents under load.


Maximum Ambient Temperature

40 °C


Class B

Degree of Protection

IP 00

Rated Output Current

0.8 - 20 A

Rated Output Voltage

0 - 250 Vac

Rated Input Voltage

230 Vac


VDE 0552

Specifications vary between configurations. Refer to the Configurations below for more information and links to the manufacturer's website.


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