Standex Electronics is a manufacturer of custom magnetic components. If you can describe it, we can manufacture it for you in most cases.

Switch mode power supplies and EMI/RFI filter assemblies typically require toroidal inductors and common mode chokes. Standex catalog toroidal inductors and common mode chokes are designed for typical switching power supply applications. We can probably meet your toroidal component requirements, large or small, with Standex standard catalog magnetic components. If our standard products don't meet your needs, let us know and we can supply a component that will, in most cases.

Standex catalog toroidal inductors and common mode chokes offer you the option of specifying the exact inductance you need without the added the cost of a 'custom' value. This option allows you to optimize your design without compromise because you are forced to use a 'standard' inductance value.

The way Standex gives you this cost effective option for large or small orders is to stock standard cores and headers for our catalog series. All of the parts on a particular series are designed on a single core. The inductance of a given inductor is a function of the number turns of wire. The current carrying capability is largely a function of wire size. All we need do to obtain the value you require is to vary the turns and the wire size

The tables of inductance's and current carrying capabilities shown for each series are essentially optimization of design charts. Mechanically, the maximum inductance shown for the CI and CJ series inductors represent the most turns we can cost effectively and efficiently wind of a given wire size on a given core. The larger the wire size (higher the current carrying capability), the less turns (inductance) we can fit on a given core. Smaller wire (less current carrying capability) results in more turns (inductance) that is possible for a given core size. Higher inductance's are available for a specific series and current rating than shown. Usually this will result in a higher cost. Please contact the factory about specific requirements.

In the case of our CM series common mode chokes, the highest inductance available represents one single layer of wire only. If more turns are put on, over one single layer, the inductance is increased, but the filtering effect of the component is greatly reduced. As noted above, the larger the wire size (higher the current carrying capability), the less turns (inductance) we can fit on a single layer on a given core.

Below is a table of the wire sizes and current carrying capabilities for our CI and CJ series differential mode toroidal inductors.