toroid iso

Phone Number: 800-867-3526


Toroid Coil Winding Factors

In the world of toroidal transformers, winding factors are the total ratio of conductor cross sections to the area of core winding. Winding factor is also typically referred to as fill factor. Depending on the toroid core, fill factors can widely vary from 20 to 60%. More commonly, an application’s winding factor will range between 30-40%.Custom Coil Winding

There are several approaches for toroid winding, which includes:

  • Single layer- The inside circumference of a core, when divided by the wire diameter, give users the number of turns toroid winding is limited to. Advantages of single layer include lower winding capacities, repeatable parasitic, low cost, and good cooling. On the other hand, it has reduced power handling, and it is more susceptible to flux leakage.
  • Full winding- typical factors (between 30 and 45%) are considered a reasonable trade-off between utilizing available space for the core and keeping manufacturing costs down.
  • High fill-  winding factors up to 65% are achievable when extra measures are taken. For high fill, each coil must be completed by hand (after residual holes become tiny and cannot fit in the winding shuttle.
  • Low fill-  when looking for reduced capacitance and ease with manufacturing, winding factors that are between single layer and 30% should be employed.

Custom Coil Winding

For more information on transformer winding and custom coil winding, please give us a call. Turn to us for toroids.

Related Reading: