model 139 GTGSs and their differences. We have
The speed and temperature channels on the
discussed the construction of the engine, its
model 139 are almost identical to the channels
systems, and its control circuits. We have also
used on the model 104 set. A few exceptions are
discussed the reduction gear, generator, and
as follows:
support systems. After studying this material and
completing the associated NRTC, you should be
The start temperature limit control valve
is not used on the model 139. No signal
able to start qualifying as an operator of the
Allison 501-K17. If your ship does not use these
is sent to it at 2,200 rpm or 12,780 rpm.
generators for electric power generation, you
should know how GTEs are used in constant
During start above 2200 rpm, the engine
speed applications.
must accelerate at a rate of 40 rpm/second
over any 3-second period. This is enabled
Chapter 8 of this training manual (TRAMAN)
by the 2200-rpm speed channel. If the
will also give you information to help you
engine fails to accelerate at that rate, an
understand shipboard electrical equipment. The
antistagnation feature will shut down the
Gas Turbine Systems Technician rating is rapidly
engine and sound the slow start alarm.
becoming one of the major ratings in the field of
shipboard power generation and distribution. To
The 1945F temperature channel has been
become a competent EPCC operator, you must
reset to 2050F. This is to allow for higher
know not only the GTGS, but also the electric
load transients. The 1880F temperature
plant of the ship.
channel remains the same.
Remember, before you attempt to operate any
ship's system, but especially one as important as
SUMMARY
a generator, follow all EOSS procedures. This will
help prevent any major casualty from occurring
In this chapter we have discussed the con-
because of operator error.
struction and operation of the model 104 and
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