CURRENT LIMIT BREAKER

PURPOSE:To increase the arc voltage as a whole and to improve the current limiting property by providing main contacts and an arc suppression loop composed by connecting in series plural switchable auxiliary contacts in a ring form or a polygonal form. CONSTITUTION:A box body 51, a switching device 52, two sets of main contacts 53, a movable contact maker 54, a set of fixing contact makers 55 are provided. Moreover, a set of input terminal and output terminal 56 and 56', and a current limit loop 58, on which plural circular arc form contacts 57 furnished between the set of fixing contact makers 55 respectively are disposed in series contacting each other in a ring form, are provided. The main contacts 53 are separated by a switching device 52 and the like when a large current is generated, and the current is turned to flow through the arc suppression loop 58 which has a small resistance. Since the generated arc 60 is divided in series plurally in the arc suppression loop 58, the arc 60 voltage is increased as a whole, and the current is limited extensively. In such a composition, the stain and deterioration of the contacts are reduced, and the current limiting performance can be improved.