488 



DYNAMO FOR ARC LAMPS 



[Cn. XIII 



FIG. 257. 



SHUNT GENERATOR CONNECTED DIRECTLY TO THE ARC LAMP 

 WITHOUT INTERVENING RESISTANCE. 



N S Poles of field magnet. 



A Armature rotating between the poles of the field magnet. 



a and b Terminals of the Dynamo. 



F Field coil; current through this coil magnetizes the iron of the field 

 magnets. 



R Adjustable field rheostat controlling the current flowing through the 

 field coil. 



L Arc lamp. 



+ and indicating the polarity of the wires connected to the arc. 



This will maintain a uniform current in the arc regardless of its length in 

 case the dynamo is properly designed and proportioned for the purpose. 



