SWITCHING EQUIPMENT 



539 



Obviously it is difficult to establish exact dividing lines which 

 will cover all conditions. The tables given in the following give 

 the instrument equipment recommended for use on the circuits 

 enumerated. Special operating conditions and requirements will 



FIG. 343. Typical Benchboard of the Gallery Type. 



often demand different measuring apparatus than that given, but 

 the table will, in all cases, serve as a guide in choosing a suitable 

 equipment. 



Instruments of each different function are valuable under 

 certain conditions or to aid in accomplishing certain results. To 



