208 



ELEMENTS OF ELECTRICAL ENGINEERING. 



The auxiliary contacts are sometimes made of carbon blocks. 

 In this case one carbon block is mounted at the extreme end of 

 the movable arm of the breaker so that when the breaker opens 

 and the arm falls back, the carbon blocks are separated widely 

 enough to put out the arc. Fig. 125 shows a single-pole carbon 



Fig. 127. 



block circuit breaker manufactured by The Cutter Company, and 

 Fig. 126 shows two single-pole carbon block breakers of the 

 Switchboard Equipment Company mounted side by side as a 

 double-pole breaker. 



Fig. 127 shows a direct- current magnetic blow-out circuit 

 breaker of the General Electric Company. In this breaker the 

 auxiliary contacts lie between the poles of an electromagnet 



