Originally Posted by john salyards
seems to be alot of questions about these specialty bbreakers where can i find them in the code book
They are defined in article 100. They are mentioned in the motor over current table. Other overcurrent protection articles can be found in 240. But overall, the code doesn't say much about them. They would be specified in a set of plans, more than a code article.
But if you don't know, an inverse-time breaker is one whose trip time is inversely proportional to the amount of overcurrent. That is, the larger the overcurrent, the faster it trips. As opposed to instantaneous-trip.
You want inverse-time on circuits that expect to have a slight overload for a short period of time, like motor circuits.