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Glass Suspension Insulators

Suspension insulators are designed to link together into strings, typically of two or more, to provide much higher voltage protection than any single insulator.  Suspension insulators are identified using the ST (Suspension Type) numbering system recently developed by Shaun Kotlarsky and Steve Coffman.  This system covers both glass and porcelain suspensions worldwide.  Suspension insulators are typically used on high tension power transmission towers as shown below.  Porcelain is by far the most commonly used insulating material but there are a number of glass styles as well.  

High Voltage Transmission

 

a side view of the 10 inch Corning Pyrex suspension insulator.  These are sometimes found with the metal removed and there is threading in the center to help the cement hold.

A Brief Overview of Glass Suspension Insulators -- ST-7000 through 7999

Note:  For more information and photo credits visit ALLINSULATORS.COM 

ST-7000-7249 -- glass cap and pin of all types 6" (152mm) and under

ST-7010

ST-7150

ST-7190

ST-7200

ST-7250-7499 -- glass cap and pin of all types 6.25 (158mm) to 9.75" (247mm)

ST-7300

ST-7310

ST-7315

ST-7400

ST-7500-7749 -- glass cap and pin of all types 10 (254mm) to 12" (304mm)

ST-7550

ST-7625

ST-7627

ST-7670

ST-7712

ST-7750-7999 -- glass cap and pin of all types Greater than 12" (304mm)

ST-7830

ST-7855

ST-7950

ST-6000-6025 -- Solid Core suspension string

ST-6000

ST-6001

 

 


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