Bi-Alpha power resistors

Salient features

  • Power 45 - 175W
  • Overload factor 5-7xPn @5s
  • Working voltage 850VAC/1400VDC
  • Dielectric strength 50Hz 1 min. 2500V
  • Protection degree IP50
  • Cooling method forced air


Danotherm has developed very flat power resistors for moderate power brake applications in drive systems, braking a few hundreds of watts to few kilowatts during a short time.

The Bi-alpha is available in 3 sizes; Bi-Alpha 4, 5 and 6. Their nominal power is rated at 45W for size 4, 100W for size 5 and 175W for size 6. These values are valid for forced air cooling of 2m/s. By increasing the airspeed the nominal power can be increased. Because of its low profile height they can easily be mounted at the back side of an VFC (Voltage Frequency Converter).

The Bi-Alpha is a simple construction where the resistor wire is wounded on a mica substrate and insulated by mica sheets on both sides. This element is enclosed in a metal alloy housing made from aluminium and zinc. The Bi-Alpha resistors are a cost effective solution for small to medium power drive systems.

Connection leads are insulated with high temperature silicon, rated at 250°C. IP value for each size is IP50.


Heatsink power resistor

Contact us:

Maarkaervej 1- 3
2630 Taastrup

+45 3673 2222

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