TAPIOCA INDUSTRY 
During the last few years a few of the factories on Java's 137 
tapioca estates have been electrified. As power becomes cheaper and 
more available, there is little doubt that many of the factories will 
be electrified. In an electrified tapioca factory the roots are carried 
by electric conveyors to tanks where they are washed by paddles that 
are also electrically driven. The roots are then placed in disinte- 
grators, which are usually operated by individual electric motors of 
about 20 horsepower. After the disintegration process the tapioca 
is drawn by suction pumps to electrically operated sieves, where it is 
sorted into the various grades. 
COPRA INDUSTRY 
A similar process is employed in the electrified copra-crushing mills 
in the Netherland East Indies. After the sun-drying process to re- 
move the moisture the copra is disintegrated by machines that are 
usually driven by electric motors of a slightly higher horsepower than 
those in the tapioca industry. The disintegrated copra is crushed to 
a meal by rollers operated by 12 to 15 horsepower motors and from 
there is pumped to the hydraulic presses by electrically driven pumps. 
ELECTRIC MOTORS 
Although motors in use in the Netherland East Indies must comply 
with the “Standardization Rules of the American Institute of Elec- 
trical Engineers” or with “Die Normalen fur Bewertung and Priifung 
von Electrischen Maschinen und Transformatoren des Verbandes 
Deutscher Electrotechniker,” comparatively few American motors 
are in use in the islands. Some of the American motors that have 
been imported in the Netherland East Indies have given excellent 
results, but many have been unsatisfactory and caused the buyers 
much trouble because the American manufacturer had not constructed 
the motors to suit the tropical climatic conditions and current char- 
acteristics of the country. As previously mentioned, 3-phase, 50- 
cycle, 127/220 volts current has been standardized, and manufac- 
turers must make their motors adaptable. Furthermore, unless 
special windings are used on the motors exported to the Netherland 
East Indies, the intense humidity causes the insulation to break 
down after a few days. 
The largest trade in alternating-current motors is in the sizes from 
5 to 25 horsepower. Larger motors are used to operate the gravel 
pumps in the tin mines and by the sugar mills, but orders for motors 
of over 100 horsepower are rare. The largest motors used in the 
Netherland East Indies are those of 250 horsepower, used in the 
electrified sugar mills. Slip-ring motors are favored and are usually 
required by the power companies. It is reported that the Govern- 
ment favors squirrel-cage motors with a double cage (high torque 
starting). Direct-current motors are used only bv factories or indi- 
viduals making their own power. 
Squirrel-cage induction motors, connected directly to the low- 
voltage distribution circuits of the public-utility companies are 
prohibited unless equipped with some form of starting equipment 
which limits the current thev take from the line at time of starting.