TDR9000
™
Circuit Breaker Test System User’s Guide
72A-1898 Rev. A 11/01 A-11
Monday, November 26, 2001 1:09 pm
Interruption in SF
6
One of the most important electrical characteristics of SF
6
(sulfur hexafluoride) is its dielectric strength. Figure A.10 shows a graph
demonstrating the dielectric strength of SF
6
and N
2
. (Reprinted from
Reference 2. Permission granted by Marcel Dekker, Inc.)
Figure A.10 60 Hz Dielectric Strength of SF
6
vs. N
2
At any given pressure the dielectric strength of SF
6
is generally three to
five times that of air.
The remainder of this discussion gives the specific information on how
Double-Pressure, Puffer Type, and Self-Extinguishing SF
6
circuit breakers
operate.
Voltage, rms, kV
Pressure, psig