What is the significance of SF6 gas pressure in 6.6kV breakers?

What is the significance of SF6 gas pressure in 6.6kV breakers?
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1 Answer

Answer :

Density gauge

Green – correct SF6 pressure (3 –3.5bar)

Yellow – pressure for breaking system fault current (refilling should be done)

Red – SF6 pressure less than 2 bar, which indicates leak in the system. 
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