Difference between Live Tank type and Dead Tank Circuit Breaker

1. Live Tank Type


   : The interrupter chamber is arranged in the insulator, which can be either porcelain or of a composite material and is at high potential with the voltage level determining the length of the insulators for the interrupter chamber and the insulator column. It sometimes needs a re-insertion resistor.

2. Dead Tank Type

   :  The interrupter chamber is accommodated in an earthed metal housing.

 

3. Live Tank Type vs. Dead Tank Type

1) Location of switching unit

   1.1) Dead-tank type: inside metallic container(earthed voltage) > cons

   1.2) Live-tank type: inside insulator bushing(live voltage) >pros

2) Amount of SF6

   2.1) Dead-tank type: 100% > cons

   2.2) Live-tank type: 10~15% > pros

3) Seismic Capability

   3.1) Dead-tank type: lower center of gravity > pros

   3.2) Live-tank type: higher center of gravity > cons

4) Location of CT
   4.1) Dead-tank type: Current Transformer can be located in bushings(BCT) > pros 
   4.2) Live-tank type: CT should be located separately > cons