Fig. 426. Rear View Chelsea Switchboard
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Fig. 427. Terminal and Power Apparatus. Chelsea Office
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A view of the terminal and power room is shown in Fig. 427. In the upper left-hand corner the cables may be seen in their passage downward from the cable turning section between the A- and B-boards. The large group of cables shown at the extreme left is the A-board multiple. This passes down and then along the horizontal shelves of the intermediate frame, which is the frame in the extreme left of this view. The B-board multiple comes down through another opening in the floor, and as is shown, after passing under the A-board multiple joins it in the same vertical run from which it passes to the intermediate frame. The cord-circuit cables lead down through the same opening as that occupied by the A-board multiple and pass off to the right-hand one of the racks shown, which contains the repeating coils. The cables leading from the opening in the ceiling to the right-hand side of the intermediate distributing frame are the answering-jack cables, and from the terminals on this side of this frame other cables pass in smaller groups to the relay terminals on the relay racks which lie between the intermediate frame and the coil rack.

The power board is shown at the extreme right. The fuse panel at the left of the power board contains in its lower portion fuses for the battery supply leads to the operator's position and to private-branch exchanges, and in its upper portion lamps and fuses for the ringing generator circuits for the various operators' positions and also for private-branch exchanges.

At the lower left-hand portion of this view is shown the battery cabinet. It is the practice of the New York Telephone Company not to employ separate battery rooms, but to locate its storage batteries directly in the terminal room and to enclose them, as shown, in a wooden cabinet with glass panels, which is ventilated by means of a lead pipe extending to a flue in the wall.

One unit of charging machines, consisting of motor and generator, is shown in the immediate foreground. A duplicate of this unit is employed but is not shown in this view. The various ringing and message register machines are shown beyond the charging machines. Three of these smaller machines are for supplying ringing current and the remainder are for supplying 30-volt direct current for operating the message registers. One of the machines of each set is wound to run from the main storage battery in case of a failure of the general lighting service from which the current for operating is normally drawn.