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BELL SYSTEM TECHNICAL JOURNAL 



Fig. 9 gives some idea as to the size of the storage batteries for a 

 typical office of this kind. The large cells in wooden tanks are those 

 making up the filament batteries, each of which is an 11-cell battery 

 of 24-volt nominal rating. These two batteries in parallel are large 

 enough to carry the office load for at least 12 hours in the event of a 

 complete failure of charging equipment. 



Fig. 10 shows the charging generators and power switchboard for a 

 typical cable repeater office. The gas engine drives emergency 

 generators to float the filament and plate batteries in the event that 



Fig. 10 — Typical Power Room for Cable Repeater Station 



the regular electric power supply service fails. Alarms are provided to 

 indicate any abnormal condition such as a voltage higher or lower 

 than normal, a blown fuse, etc. These are grouped in an annunicator 

 cabinet on the wall. 



Test Board Equipment 



The test board forms an important part of the cable plant equip- 

 ment, since it is the one point in the office where all of the lines and 

 the equipment as a whole may be reached readily for purposes of 

 testing or re-routing, in cases of line trouble or changes in layout. 

 The form and arrangement of the test board equipment consequently 

 have an important bearing on the effectiveness with which the facilities 

 are handled by the maintenance forces. This is particularly true in 

 the cable plant where the number of circuits involved is large. 



