Difference Between Live and Dead Tank Circuit Breakers 

By on


Siemens Dead Tank Circuit Breaker
A quick post in connection with an email question:

Live Tank -  the circuit breaker the switching unit is located in an insulator bushing which is live at line voltage (or some voltage above ground). Live Tank circuit breakers are cheaper than dead tank and require less space.

Dead Tank -  the switching unit is located within a metallic container which is kept a earth potential.  As the incoming/outgoing conductors are taken through insulated bushings, it is possible to place current transformers on these (with a Live Tank arrangement this is not possible and separate CTs are required). 

The terms Live and Dead Tank normally only apply to high voltage circuit breakers



Steven McFadyen's avatar Steven McFadyen

Steven has over twenty five years experience working on some of the largest construction projects. He has a deep technical understanding of electrical engineering and is keen to share this knowledge. About the author

myElectrical Engineering

comments powered by Disqus

  1. tang's avatar tang says:
    8/23/2012 8:15 AM

    What is the ground clearance for dead tank CT?

    • Steven's avatar Steven says:
      8/26/2012 12:17 PM

      With a dead tank circuit breaker, the CT primary side is still isolated, so I'm not sure about why you are worried with ground clearance.


Comments are closed for this post:
  • have a question or need help, please use our Questions Section
  • spotted an error or have additional info that you think should be in this post, feel free to Contact Us



Electromechanical Relays

Electromechanical relays have been the traditional backbone of electrical protection systems.  While over recent years these have been replaced by microprocessor...

Lead Acid Batteries

Lead acid batteries are cost effect and reliable, making them suitable for many applications.This note examines topics of interest associated with the...

Alternating Current Circuits

Alternating current (a.c.) is the backbone of modern electrical power distribution. In this article I’ll be pulling some of the more important concepts...

Dielectric loss in cables

Dielectrics (insulating materials for example) when subjected to a varying electric field, will have some energy loss.   The varying electric field causes...

Induction Motor Equivalent Circuit

Induction motors are frequently used in both industrial and domestic applications.  Within the induction motor, an electrical current in the rotor is induced...

Low Voltage Switchroom Design Guide

Low voltage (LV) switchrooms are common across all industries and one of the more common spatial requirements which need to be designed into a project...

Our internet address and Vanity URLs

Visitors who like to type web address rather then click menus may be interested in how our URL structure works.

Thomas Edison

American inventor Thomas Alva Edison was born in Milan, Ohio on February 11, 1847. He was the youngest of seven children and received little formal schooling...

Are We Losing Professional Integrity

I have been thinking recently that there appears to be less professional integrity around than when I first started my career in electrical engineering...

Three Phase Power Simplified

A single phase system is perhaps the most common type of system most people are familiar with. This is what people have in their homes and what appliances...

Have some knowledge to share

If you have some expert knowledge or experience, why not consider sharing this with our community.  

By writing an electrical note, you will be educating our users and at the same time promoting your expertise within the engineering community.

To get started and understand our policy, you can read our How to Write an Electrical Note