doble TDR9000, User Manual, Page: 215 / 454

TDR9000
™
Circuit Breaker Test System User’s Guide
72A-1898 Rev. A 11/01 A-15
Monday
, November 26, 2001 1:09 pm
Live Tank vs. Dead Tank
In the dead-tank design, shown in Figure A.14, the interrupting elements
are enclosed in a grounded metal tank and the line and bus conductors
enter the interrupting chamber through entrance bushings.
Figure A.14 Dead-Tank Circuit Breaker Schematic
In the live-tank design, as shown in Figure A.15, the circuit breaker
interrupters are mounted in a container at line potential and are insulated
from ground potential using porcelain insulating columns. The major
advantage of the live tank is its lower cost, especially at a higher voltage
rating.
A major disadvantage is that it requires externally mounted current
transformers, which are more expensive and require more substation
space than bushing current transformers.
Figure A.15 Live-Tank Circuit Breaker Schematic
Bus Line
Current
Transformers
Bus Line
Main Current
Transformers