EC: Sinusfilter Plus++

Network Integration — Signal Conditioning, Diagnostics: The Sinusfilter Plus++ output filters are designed for common-mode, high-frequency interference. This is a Control Engineering 2015 Engineers’ Choice finalist.

By Control Engineering October 20, 2014

The Sinusfilter Plus++ is a combination of conventional differential and common-mode filters and is connected to the dc-link circuit to provide a low impedance path back to the source of the parasitic currents. Spindle-bearing currents in the motor originate from the dc-link and so protection of the mechanical system is ensured. In addition to the reduction of switching disturbances, radio frequency interference on the input side of the inverter is also reduced and the general EMC is greatly enhanced.

In long cable lengths, such as those necessary for use in heat-pumps or high-rise buildings, the common-mode disturbances take the path of lowest impedance back to earth. These disturbances can also cause inaccurate and unacceptable measurement of water flow-rates. Again, this problem can be solved by using the Sinusfilter Plus++.

In any application where long cable runs and common mode RF interference cause massive problems, the Sinusfilter Plus++ is the best choice for providing long-term protection of mechanical equipment, and also insurance for the plant operator against costly repairs, or in the worst case replacement of a complete system.

Conforming to EN 61558-2-20, it has a rated voltage of V=3×500 V and insulation material class of T40/B. The advantages of the REO Sinusfilter Plus ++ include:

  • Voltage distortion factor Uout <5%
  • Reduces the need for a complex EMC Input Filter
  • Use of unshielded cables
  • No need for external line filters
  • Lower magnetic stray field of motor conductors
  • Compact and low noise construction.

REO Inductive Components,