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Porcelain Post Insulators

Post insulators have a metal bolt down base as opposed to threads.  The Lapp insulator company originated the line post which quickly replaced the porcelain pin type insulator as the most popular for medium voltage transmission.  Many early multipart lines are spotted with line post insulators as replacements.  Post insulators are also used in substations to insulate high voltage switching gear and transformers.  There is no hobby numbering system for post insulators yet.

Line Post

Here is a sky glaze porcelain line post insulator.  The metal base has a threaded hole to bolt to the cross-arm.

Station Post

Here is a porcelain station post.  These insulators could be stacked to support additional voltage insulation.  Switch or distribution gear could be mounted to the top.



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