Product Description


AT3 Series


Fixing rail, PRI 3 x 200/208 Vac - 3 x 690 Vac, SEC 3 x 400 Vac, 2,000 - 250,000 VA


  • Enlarged mounting bracket for easy installation from above
  • Integrated crane eyes
  • Multi-functional mounting brackets with 12 slots
  • Fixed, contact protected screw connection terminals complying with UVV BGV A3
  • Very good corrosion protection and low noise thanks to BLOCK IMPEX vacuum impregnation
  • Patented assembly technology to lower heat losses
  • Very high efficiency
  • Reverse mode possible



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


Autotransformer for adjustment of the voltage on the input and output sides with no requirement for electrical isolation.


Rated Power

2,000 - 250,000 VA


Up to 98 %

Maximum Ambient Temperature

40 °C


Class F

Degree of Protection

IP 00

Optionally adapted package for higher degrees of protection

Rated Output Voltage

3 x 400 Vac

Rated Input Voltage

3 x 200/208 - 3 x 690 Vac


VDE 0570 Teil 2-13, DIN EN 61558-2-13, EN 61558-2-13, IEC 61558-2-13


UL 5085-1/-2, CSA 22.2 No.66

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


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