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8

Mechanical properties

8.1

Potting (economy potting, complete potting)

We distinguish between economy potting and complete potting.

Economy potting is used to fix the the core and windings in the case and the windings on the core.

This is an economical technique which enables a single resin casting procedure to be used. Be-

cause of this, most chokes supplied by EPCOS are produced using this method.

Complete potting is only required when the thermal conductitvity of economy potting is not adequate

or if the customer has special demands. Complete potting requires several process steps to ensure

complete embedding of the core and the windings.

8.2

Types of winding

EPCOS uses different types of winding to suit the respective technical requirements:

– single-layer winding

– multilayer winding

– random winding

The different types of winding lead to different inductance characteristics, especially at high fre-

quencies.

Single-layer winding:

The winding pitch is equal to or greater than the wire diameter. The coil is wound in one direction

only. The only capacitances (parasitic capacitances) are those between one turn to the next. In

comparison to all other types of winding, this type of winding leads to the lowest possible capaci-

tances and thus the highest resonance frequencies.

Economy potting

Complete potting

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General Technical Information