Tape-wound cores are made from softmagnetic metallic thin tapes. They feature the highest permeabilities and an excellent temperature stability.
Cores from crystalline NiFe-alloys (ULTRAPERM®) are used at low to medium frequencies. Amorphous (VITROVAC®) and especially nanocrystalline alloys (VITROPERM®) however are attractive options against ferrites at higher frequencies for many applications.
The toroidal shape is due to the the evenly distribution of the magnetic flux ideal for soft magnetic cores as the magnetic properties are not degraded by geometrical influences. Consequently, toroidal shapes are often used in combination with gigh grade magnetic alloys. Nanocrystalline Fe-based alloys have turned out to be of special interest as they combine excellent magnetic properties with reasonable costs, a very good temperature stability and favorabgle frequency properties.
Main applications for tape-wound cores are Common Mode Chokes, precise Current Transformers, fast Pulse Transformers, Power Transformers and Magnetic Amplifiers.
Notes on tape-wound cores
Please note that tape-wound cores are made from thin metallic tapes. Due to the surface roughness of the tapes the effective magnetic cross section is about 80 % of the geometric cross section. Furthermore certain tolerances of the outer dimensions need to be considered, which are defined as limiting values in the data sheets.
Please find additional information about the part numbers and the fixation of the tape-wound cores from VACUUMSCHMELZE GmbH & Co. KG in the download below.
Standard series tape-wound cores, VITROVAC® (amorphous) and VITROPERM® (nanocrystalline) Further information and tables 4 MB
Brochure "SEKELS - Prducts & Services" Further information and some hints on how to understand the part number and the fixation 3 MB