Notes

Difference Between Live and Dead Tank Circuit Breakers 

By on


Siemens Dead Tank Circuit BreakerA 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

, ,

More interesting Notes:
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

View 2 Comments (old system)

  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
MIT OpenCourseWare

MIT OpenCourseWare, makes the materials used in teaching all MIT subjects available on the Web, free of charge, to any user in the world.

RLC Circuit, Resistor Power Loss - some Modelica experiments

Modelica is an open source (free) software language for modelling complex systems. Having never used it before, I thought I would download a development...

IEC Reference Designations

The IEC publishes a series of documents and rules governing the preparation of documents, drawings and the referencing of equipment.   Depending on country...

Closed Doors

"I can live with doubt and uncertainty and not knowing. I think it is much more interesting to live not knowing than to have answers that might be wrong...

UPS Battery Sizing

Various techniques exist to enable the correct selection of batteries for UPS applications.  The procedure described below is one of the more common. ...

Understanding Motor Duty Rating

One of the comments on my Motor Starting Series was asking for something on duty cycles. Here it is. As a purchaser of a motor, you have responsibility...

Cost Performance and Time

Often us engineers get so bogged down in equations, using software, producing drawings and writing specifications that this becomes the sole focus.   ...

Electromagnetic Compatibility (EMC)

Electromagnetic compatibility (EMC) is the study of coordinating electromagnetic fields give off equipment, with the withstand (compatibility) of other...

Power Transformers - An Introduction

One of the fundamental requirements of an alternating current distribution systems it to have the ability to change the magnitude of voltages.  It is more...

What does N+1 mean?

The term 'N+1' relates to redundancy and simply means that if you required 'N' items of equipment for something to work, you would have one additional...

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. 

Footer
(click here to extend)
Copyright (c) 2026 myElectrical