BATTERY CHARGER UNIT FOR SPECTROPHOTOMETER 



117 VAC 60 CYC. 

 1 



SPST SWITCH 



2 AMP. FUSE 

 ^^^ 



i 



2 AMP. FUSE 



— ^y^— 



RATE OF CHARGE METER 



t 



iiJLSULSLSUiJUli TRANSFORMER # I 



• SELENIUM 

 RECTIFIER 



CIRCUIT 

 BREAKER 



0-50 

 MILLIVOLTS 



DC 

 — » •— 



TRANSFORMER #2 ifiJM^MM' 



0083 AvMETER SHUNT 



3PDT SWITCH 



2PDT SWITCH 

 CENTER OFF 



+ 6 +2 - 



DC SUPPLY TO 



SPECTROPHOTOMETER 



VOLT 160 AMP/HOUR STORAGE BATTERY 



Figure 5. --Wiring diagram (semidiagrammatic) of battery charger unit. 



if the volume of water to be filtered 

 is to be kept below 6 liters. The 

 measurement of extinction at the vari- 

 ous wave lengths has been made less 

 time consuniing by the construction 

 of a cell holder which will accommodate 

 as many as four semimicroabsorption 

 cells. 



DISCUSSION AND CONCLUSIONS 



While the modifications described 

 are not in any sense radical, they have 

 greatly simplified the maintenance and 

 operation of the DU Spectrophotometer 

 both in the laboratory and especially 

 on oceanographic research vessels. In- 



struments provided with these modifi- 

 cations have given virtually trouble- 

 free operation over the past 2 years 

 under most severe field conditions. 



The authors have not used the Beck- 

 man 14500 battery power regulator nor 

 the newer batteryless power supply 

 (Beckman 23700) under field conditions . 

 These units, especially the latter, have 

 not been so employed because they 

 would require special skills in repair- 

 ing. Furthermore, spare parts for such 

 equipment are not generally available 

 in foreign ports, whereas batteries 

 such as are used in the conventional 

 DU Spectrophotometer power supply 

 are available abnost everywhere. 



MS #1063 



GPO 91450S 



