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Please read Cautions and warnings and

Important notes at the end of this document.

Mechanical stress and mounting

Ferrite cores have to meet mechanical requirements during assembling and for a growing number

of applications. Since ferrites are ceramic materials one has to be aware of the special behavior

under mechanical load.

As valid for any ceramic material, ferrite cores are brittle and sensitive to any shock, fast tempera-

ture changing or tensile load. Especially high cooling rates under ultrasonic cleaning and high static

or cyclic loads can cause cracks or failure of the ferrite cores.

For detailed information see data book, chapter “General - Definitions, 8.1”.

Effects of core combination on AL value

Stresses in the core affect not only the mechanical but also the magnetic properties. It is apparent

that the initial permeability is dependent on the stress state of the core. The higher the stresses are

in the core, the lower is the value for the initial permeability. Thus the embedding medium should

have the greatest possible elasticity.

For detailed information see data book, chapter “General - Definitions, 8.1”.

Heating up

Ferrites can run hot during operation at higher flux densities and higher frequencies.

NiZn-materials

The magnetic properties of NiZn-materials can change irreversible in high magnetic fields.

Ferrite Accessories

Our ferrite accessories have been designed and evaluated only in combination with our ferrite

cores. We explicitly point out that our ferrite accessories or our ferrite cores may not be compatible

with those of other manufacturers. Any such combination requires prior testing by the customer and

will be at the customer‘s own risk.

We assume no warranty or reliability for the combination of our ferrite accessories with cores and

other accessories from any other manufacturer.

Processing remarks

The start of the winding process should be soft. Else the flanges may be destroyed.

– Too strong winding forces may blast the flanges or squeeze the tube that the cores can not be

mounted any more.

– Too long soldering time at high temperature (>300 °C) may effect coplanarity or pin arrange-

ment.

– Not following the processing notes for soldering of the J-leg terminals may cause solderability

problems at the transformer because of pollution with Sn oxyde of the tin bath or burned insula-

tion of the wire. For detailed information see chapter “Processing notes”, section 2.2.

– The dimensions of the hole arrangement have fixed values and should be understood as

a recommendation for drilling the printed circuit board. For dimensioning the pins, the group

of holes can only be seen under certain conditions, as they fit into the given hole arrangement.

To avoid problems when mounting the transformer, the manufacturing tolerances for positioning

the customers’ drilling process must be considered by increasing the hole diameter.

Cautions and warnings

Ferrites and accessories

Cautions and warnings