CAT Titan 250 Manual De Usuario

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Turbomachinery Package Specification 
Titan 
250 Generator Set 
The fuel control valve gradually opens and admits fuel into the combustor through the 
injectors. The inlet guide vanes open and the bleed valve gradually closes. Fuel flow, 
engine temperature, and turbine speed all increase. Once starter dropout speed is 
exceeded, the starter freewheels and is de-energized. The engine continues to 
accelerate under its own power. 
The generator is loaded by closing the generator circuit breaker. The circuit breaker can 
be closed to a dead (de-energized) or a hot (energized) bus. If a dead bus is detected, 
the circuit breaker may be closed without synchronization. If a hot bus is detected, the 
system must synchronize the generator output to the bus before the circuit breaker is 
closed. Typically, synchronization and closing of the breaker are done automatically. 
Manual synchronization is available as an option. 
9.4.2 Steady-State 
Control 
During steady-state operation, the control system keeps the equipment within specified 
operating conditions. The maximum power limit is determined by engine temperature and 
speed. 
Temperature control is based on the third-stage nozzle temperature (T5). A set of 
thermocouples arranged circumferentially around the turbine are used and the values 
averaged. If one thermocouple has a value that deviates from the average by more than 
a preset amount, an alarm is generated by the control system. If two thermocouples 
deviate, the package is shut down. 
Special sensors continuously monitor the gas turbine speed and the control system 
makes adjustments to meet operating requirements and to keep the speed within 
specified limits. A separate backup overspeed detection system provides additional 
protection by automatically shutting the engine down if a preset overspeed limit is 
reached. 
9.4.3 Stopping 
The gas turbine may be shutdown either manually or automatically. 
The  Normal Stop command initiates a cooldown stop. The generator circuit breaker is 
opened and the gas producer runs at idle speed for a preset time to allow the gas turbine 
and driven equipment to cool, then the fuel valves close. The Emergency Stop 
command results in the immediate opening of the generator circuit breaker and closure of 
the fuel valves without a cooldown period. 
In the event of a hazardous condition or equipment malfunction, the control system will 
shut the package down automatically. These shutdowns are divided into four categories: 
•  Cooldown stop nonlockout (CN) 
•  Cooldown stop lockout (CL) 
•  Fast stop nonlockout (FN) 
•  Fast stop lockout (FL) 
Cooldown and fast stops correspond to the manual normal and emergency stops 
respectively. Lockout stops inhibit operation of the control system and prevent restarting 
until the malfunction is reset. Lockout stops result from serious malfunctions that require 
corrective action before the system can be restarted. Nonlockout stops result from an 
operational disruption or abnormal condition and can be reset when conditions return to 
normal. 
To protect the rotor from deformation and to enable a prompt restart of the package, the 
turbine does not come to a complete stop unless the shutdown is the result of fire being 
detected. The starter motor, or the DC backup turning gear mechanism in the case of 
loss of AC power, engages the turbine at low speed and maintains rotation until the 
cooldown cycle is complete. At the same time, the control system initiates and supervises 
© 2008 Solar Turbines Incorporated. All rights reserved. 
TPS250GS/908 - Preliminary 
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