200 ELECTRIC PUMPING EQUIPMENT AND NOTES OF INTEREST ON 
These turbines exhaust into the auxiliary condenser, but it is also arranged so 
that they can exhaust into the main condenser. While discharging, the larger tur- 
bine is of sufficient size to operate nine pumps at about 140 pounds pressure, and 
for general purposes this is the maximum number of pumps that can be operated at 
one time with present shore discharge lines. However, necessary arrange- 
ments are made to operate both generators in parallel, making a total capacity of 
500 K-va; this would permit the operation of eleven to twelve pumps at the same 
pressure. In case of any trouble with the large turbine, the smaller unit could be 
used to operate two to three of the cargo pumps. When at sea, the 125 K-va tur- 
bine is used, exhausting into the main condenser; this turbine is of sufficient size 
to operate the boiler feed, main circulating pump and lights. In case of any trouble 
with the 125 K-va turbine, the larger turbine could be used. With the above ar- 
rangement there is always one turbine available as a spare. 
For furnishing lights, there are supplied two transformers stepping voltage 
down from 240 to 120. To furnish the necessary power for the lights when both 
the above turbines are shut down, there is a small 5-kilowatt, 125-volt engine- 
driven, direct-connected generator available. 
The switchboard is shown on Fig. 14, Plate 122, and is installed on a gallery 
on the starboard side of the engine-room. Starting from left to right, the switch- 
board consists of the following :— 
One swinging bracket, one synchronizing device, used for paralleling the two 
turbines and the voltage regulator. 
Panel 1 controls the two direct-connected exciters of the turbine sets. 
Panel 2 controls the 125 K-va generator set. 
Panel 3 controls the 375 K-va turbine set. 
Panel 4 controls the feeder lines to the motors in the engine-room and the com- 
pensators used for starting the cargo pump motors. 
Panels 5, 6 and 7 control the twenty-two circuits to the cargo pump motors. 
Panel 8 is the lighting panel and controls the 5-kilowatt generating set and the 
auto transformers which changes the voltage from 240 to 110. It is so arranged that 
lights can be operated either from the main generating sets or the small auxiliary 
5-kilowatt set. 
One of the novel features in connection with this installation, and which is 
part of the switchboard, is the method of starting the cargo pumps. Ordinarily the 
practice is to use a starting compensator with each squirrel-cage motor. For various 
reasons it was not considered advisable to. use any starting devices where the cir- 
cuit would be made or broken on the upper deck, on account of possible presence of 
explosive gases, and a scheme was worked out by which all the motors were started 
from the engine-room switchboard. 
Arrangements were also made to start all motors from two compensators, one 
of which is a spare. This is accomplished as follows:—The three panels, 5, 6 and 
7, controlling the cargo pump motors, have running and starting buses, the running 
bus energized direct from the generators, and the starting bus through the compen- 
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