Over the course of the next several upcoming articles, we will present the basics of the behavior of the contact mechanism and the physics of the arc which is present in all electromechanical overcurrent protection devices.

Our discussion of contacts will consider both the electrical and mechanical characteristics of contacts in circuit breaker mechanisms.

Following our review of contacts, we will discuss the development of a simple dynamic thermal model which we will use to consider arc behavior within AC and DC electrical circuits.  

In this context, our next article will consider contact resistance and contact parting dynamics.