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BULLETIN OF THE BUREAU OF FISHERIES 



DESIGN OF ELECTRIC FISH SCREENS 



In this discussion of the design of electric fish screens no attempt will be made to 

 discuss the details of mechanical construction, because these may be altered greatly 

 by local conditions. The electrical design, however, is fundamental and contains 



Fig. 17 



conditions that must be met to obtain satisfactory operation. These conditions, 

 stated very briefly, are as follows: 



1. An insulating transformer should be used between the power supply and the 

 screen to avoid a useless current flow from the electrodes to ground. 



2. The lines of current flow in the electric field must be perpendicular to the 

 plane of the protected opening and the equipotential surfaces parallel with this 

 plane. (See figs. 10 and 12.) 



