538 



ELECTRICAL EQUIPMENT 



the present time in the form of an L, although ultimately it will be 

 in the form of a U with the dispatcher board in the center. 



Diffused illumination in the control room is provided by means 

 of a skylight, which forms the entire ceiling. In order to prevent 

 glare on the instruments it also became necessary to provide amber- 

 colored glass in the windows. At night a diffused illumination is 

 accomplished by tungsten lamps, which are mounted back of the 

 skylight panes. 



Instrument Equipment. The instrument and meter equip- 

 ment for any particular installation should be chosen with the idea 



FIG. 342. Typical Benchboard of the Continuous Type. 



of getting something which is satisfactory from an engineering 

 standpoint, at the same time keeping in mind its cost in proportion 

 to that of the total installation, and also considering the class of 

 attendants who will operate the board. It is not good economy 

 to invest in an elaborate set of instruments when the man who 

 operates the plant does not understand their use. In the large 

 installations, where more intelligent help is employed, the efficiency 

 of the plant can be greatly improved by the use of instruments 

 which are understood, but which would be more than useless in 

 the hands of the unskilled attendant. 



