Difference Between SF6 and Vaccum CB

Hi

Vaccum is better for < 66kV application for > 66 kv sf6 is recommended due to superior dielectric strenght and quenching capabilities .

Please find here some useful information

A simple check of the different switchgear manufacturer's product lines will show you that for indoor switchgear (and circuit breakers) below around 33kV Vacuum is preferred, and for 33kV and above SF6 is preferred. This is a rough guide only and may vary depending on personal preference, manufacturer electrical standards and user application.

If you are totally confused, look at the major MV or HV (depending on what country and standard you are specifying to) switchgear and circuit breaker manufacturer websites for available product lines and application guidance.