2A652 Volume 3 CDC Pretest

When operating a gas turbine engine, it is important to use earplugs and muffs to protect your hearing from the loud noise produced by the engine. Additionally, you should never enter the plane of rotation, as this can be extremely dangerous and can result in severe injuries or even death. Lastly, it is also crucial to stay away from the rear of the engine, as there may be hot exhaust gases or other hazards present. Therefore, the correct answer is "all of the above" as all three options are necessary precautions to ensure safety when operating a gas turbine engine.

A three-phase generator is capable of supporting three different loads at the same time because it generates three separate alternating currents that are 120 degrees out of phase with each other. This allows for a balanced distribution of power to each load, ensuring efficient and stable operation. Additionally, the three-phase system provides higher power output compared to single-phase or two-phase generators, making it suitable for powering multiple devices simultaneously.

When using a load bank to test a generator, it is important to follow the procedures outlined in both the generator Technical Order (TO) and the load bank TO. The generator TO provides specific instructions and guidelines for operating and testing the generator, while the load bank TO provides instructions for connecting and operating the load bank. By following the procedures outlined in both TOs, one can ensure that the generator is properly tested using the load bank and that accurate results are obtained.

After shutdown, a motor continues turning due to inertia. Inertia is the tendency of an object to resist changes in its motion. In the case of a motor, when it is suddenly turned off, the moving parts of the motor, such as the rotor, continue to spin due to their momentum. This is because the motor requires some time to come to a complete stop as the force that was driving it is no longer present.

Preventive maintenance is the most cost-effective and efficient method of reducing injection equipment problems and maintenance costs. This approach involves regularly inspecting and servicing equipment to prevent breakdowns and identify potential issues before they become major problems. By conducting routine maintenance tasks such as cleaning, lubricating, and replacing worn parts, the likelihood of equipment failure is significantly reduced. This proactive approach helps to extend the lifespan of the equipment, improve its performance, and minimize the need for costly repairs or replacements.

Before connecting a generator set to the load bank, it is important to make sure that all on-off switches are in the OFF position. This is necessary to ensure that the generator and load bank are properly synchronized and to prevent any potential damage to the equipment or injury to personnel. By ensuring that all switches are in the OFF position, it allows for a safe and controlled connection between the generator set and the load bank.

To find out where a wire is connected, you should consult the wiring diagram. A wiring diagram is a visual representation of the electrical connections and components in a system. It provides detailed information about the routing and connections of wires, allowing you to locate the specific connection point for a wire. By referring to the wiring diagram, you can accurately determine where a wire is connected within the system.

A mechanical injector is operated by a rocker arm. The rocker arm is responsible for opening and closing the injector valve, allowing fuel to be sprayed into the combustion chamber. This type of injector is commonly found in older vehicle models and is known for its durability and reliability. Unlike other types of injectors, such as pintle or pressure injectors, the mechanical injector does not rely on electronic components or sensors for operation. Instead, it is mechanically controlled, making it a simpler and more straightforward design.

When a lubricant reduces friction, it also reduces heat, wear, and resistance. This is because lubricants provide a protective layer between two surfaces, allowing them to slide smoothly against each other. By reducing friction, the lubricant minimizes the generation of heat, which can cause damage to the surfaces. Additionally, the lubricant prevents wear by reducing the contact and friction between the surfaces. Lastly, lubricants help to reduce resistance, making it easier for the surfaces to move and operate efficiently. Therefore, all of the given options are correct.

The radiator holds a large amount of coolant in close contact with a large volume of air. As the hot coolant flows through the radiator, it releases heat to the surrounding air, which helps in cooling down the coolant. The radiator is designed with a series of tubes and fins that increase the surface area for better heat transfer. This allows for efficient cooling of the coolant before it is circulated back into the engine.

The filtration step in a diesel engine fuel system is necessary to protect the system from abrasion caused by foreign particles. These particles can enter the fuel system and cause damage to various components, such as the fuel injectors and fuel pump. By using a filtration step, these particles are removed from the fuel before it reaches the engine, preventing any potential abrasion and ensuring smooth operation of the fuel system.

The starter motor is responsible for rotating the turbine engine during the starting process. It provides the initial power to get the engine moving and build up the necessary momentum for combustion to occur. The AC generator, tachometer generator, and fuel pump and control unit are not directly involved in the starting process.

The A/M24T-8 electrical test set is capable of testing both AC and DC power supplies. This means that it can be used to assess the functionality and performance of electrical equipment that operates on both types of power sources. It provides a comprehensive testing solution for a wide range of power supplies, making it a versatile tool for electrical testing and troubleshooting.

Torque is defined as rotational force. It is the measure of the force that can cause an object to rotate around an axis. It is commonly used to describe the twisting or turning force applied to an object, such as a wrench turning a bolt. Torque is dependent on both the magnitude of the force and the distance from the axis of rotation. It is often measured in units such as Newton-meters (Nm) or foot-pounds (ft-lb).

A visual inspection is the first thing you should do when troubleshooting a motor because it allows you to quickly identify any obvious issues or abnormalities. By visually inspecting the motor, you can check for loose connections, damaged wires, burned-out components, or any other visible signs of damage or malfunction. This initial inspection can help determine if further testing or repairs are necessary, saving time and effort in the troubleshooting process.

Operating the engine unloaded before loading and after unloading the GTC (Gas Turbine Compressor) helps to reduce thermal stress. When the engine is not under load, it experiences less strain and heat, which can prevent damage caused by excessive temperatures. This practice allows the engine to cool down and stabilize before being subjected to heavy loads or during shutdown, ensuring its longevity and efficient operation.

The correct answer is "an equipment condition check". This is because a service inspection involves thoroughly analyzing the unit and checking the condition of the equipment. It is not specifically a weekly or daily requirement, but rather a process that is done to ensure the equipment is in proper working condition.

A lubricant circulates past the air surrounding the oil sump in order to cool the system. As the lubricant flows, it absorbs heat from the engine components and carries it away, preventing overheating. This helps to maintain the optimal operating temperature and prevents damage to the engine. Cooling is an essential function of a lubricant to ensure the efficient operation and longevity of the engine.

The cooling air for the transformer rectifier in a gas turbine engine is provided by the cooling fan. The cooling fan is responsible for circulating air to remove heat from various components, including the transformer rectifier. This helps to prevent overheating and ensures the proper functioning of the engine.

Air-oil seals are used to prevent oil loss into the airflow system during turbine engine operation. These seals create a barrier between the oil and the airflow, ensuring that the oil remains contained within the engine and does not escape into the airflow. This helps to maintain the proper functioning of the engine and prevents any potential damage or contamination that could occur due to oil loss. Oil-tank baffles, exhaust-vent line, and pressure-relief valve do not directly address the issue of oil loss into the airflow system, making them incorrect options.

To produce an electromotive force (EMF) mechanically, three things are necessary: a magnetic field, a conductor, and relative motion between the two. The magnetic field induces a force on the conductor, causing the electrons within it to move. This movement of electrons creates an electric current, resulting in the generation of an EMF. Without any one of these three components, the production of EMF mechanically would not be possible.

To prevent abnormal amounts of carbon, moisture, and sludge build-up in a diesel engine, it is best to avoid operating the engine for extended periods at no-load. When an engine operates at no-load, it means it is running without any external load or resistance. This can lead to incomplete combustion, which in turn causes carbon deposits and build-up of moisture and sludge in the engine. By avoiding extended periods of no-load operation, the engine can maintain proper combustion and reduce the risk of carbon, moisture, and sludge accumulation.

In a gas turbine engine, the air is accelerated by the impellers. Impellers are rotating components that are responsible for drawing in and compressing the air before it enters the combustion chamber. They increase the velocity of the air by rotating at high speeds, which creates a low-pressure area and sucks in more air. This accelerated air is then directed towards the diffusers, exducers, and deswirl ring for further processing and combustion. Therefore, impellers play a crucial role in the initial acceleration of the air in a gas turbine engine.

The drain valve is the turbine engine component that prevents fuel from accumulating in the plenum. This valve allows any excess fuel or other liquids to be drained out of the system, preventing them from building up and causing potential damage or malfunction. By removing the accumulated fuel, the drain valve helps maintain proper functioning and safety of the turbine engine.

During a preoperation inspection of a gas turbine engine, it is important to check the intake and exhaust for foreign objects. This is because any foreign objects, such as debris or particles, can potentially enter the engine and cause damage to the internal components. By checking for foreign objects, the technician ensures that the engine operates smoothly and efficiently without any obstructions. This inspection helps to prevent any potential issues or malfunctions that could arise from the presence of foreign objects in the engine.

The stator windings of a synchronous motor are wound 120 degrees apart. This is because a synchronous motor requires a rotating magnetic field to operate. By winding the stator windings 120 degrees apart, the resulting magnetic field produced by the windings will have a phase difference of 120 degrees. This phase difference is necessary for the motor to synchronize with the rotating magnetic field produced by the rotor, allowing for efficient and smooth operation of the motor.

When oil enters the airflow system, it can cause gray or white smoke to pour from the exhaust stack on the GTC. This is because the oil mixes with the fuel and air, resulting in the smoke being emitted from the exhaust.

If combustion does not occur within 15 seconds after placing the start switch in the ON position, the operator must stop the unit. This is because the generator set is not functioning properly and continuing to run it without combustion can potentially cause damage or pose safety risks. Stopping the unit allows the operator to assess the issue and take appropriate measures to troubleshoot and fix the problem before attempting to start it again.

The purpose of the protective circuits of the A/M32A-86D is to protect the aircraft electrical system against damage that could occur due to various factors such as overload, overvoltage, undervoltage, and over/underfrequency. These protective circuits are designed to detect fault conditions and prevent any potential harm to the electrical system by stopping the generator. By doing so, they ensure the safe and efficient operation of the aircraft's electrical system.

The three-phase induction motor does not require a starting device because it is a self-starting motor. This is because the rotating magnetic field created by the stator induces currents in the rotor, which causes it to start rotating. The slip, which is the difference between the synchronous speed of the rotating magnetic field and the actual speed of the rotor, is necessary for the motor to operate efficiently. However, a separate starting device is not needed as the motor can start on its own.

During a compression test, the allowable deviation between cylinders refers to the acceptable difference in compression pressure readings between individual cylinders in an engine. The correct answer of 25 psi suggests that a variance of up to 25 psi is considered acceptable between cylinders. This means that if the compression pressure readings of all cylinders fall within a range of 25 psi, the engine is considered to have balanced compression and is functioning properly.

The AC control panel contains all the necessary controls to test an AC generator with reactive loads. Reactive loads are loads that require both active power (real power) and reactive power (imaginary power) to operate. These loads include inductive loads, such as motors and transformers, which require reactive power to create and maintain magnetic fields. The AC control panel would have the necessary controls to adjust and measure the reactive power output of the generator during load testing.

The auxiliary fuel tank on the A/M32A-60A generator set automatically transfers fuel to the main tanks. This means that the transfer process does not require any manual intervention or control. The transfer occurs when the main tanks are empty, ensuring a continuous fuel supply to the generator set. Additionally, the transfer may also happen at regular predetermined time intervals, further ensuring that the main tanks are always adequately fueled.

The advantage of a three-phase induction motor over a comparable single-phase unit is its high starting torque. This means that the motor can handle heavier loads and start them more efficiently, making it suitable for applications that require high torque at startup. The high starting torque allows the motor to quickly accelerate and overcome inertia, making it more reliable and efficient in various industrial and commercial settings.

When using a troubleshooting chart, you are not likely to find "Analysis" as it is not a typical component of a troubleshooting chart. A troubleshooting chart is designed to provide a step-by-step guide to identify and resolve problems, typically listing symptoms, probable causes, and remedies. Analysis, on the other hand, refers to the process of examining and evaluating data or information, which is not typically included in a troubleshooting chart.

Cleaning solvents can cause damage to the brushes in an electrical component. The solvents can dissolve the material of the brushes or cause them to become brittle, leading to their deterioration or breakage. Brushes are crucial for the proper functioning of the component as they make contact with the commutator or slip rings, transferring the electrical current. If the brushes are damaged, it can result in poor electrical contact, reduced performance, or even complete failure of the component. Therefore, it is important to handle cleaning solvents with caution to avoid damaging the brushes.

The correct answer is governor. A governor is a device used in turbine engines to maintain a constant speed. It regulates the flow of fuel to the engine based on the load and speed requirements. By adjusting the amount of fuel supplied, the governor ensures that the engine maintains a consistent speed, even when the load changes. This helps to optimize the performance and efficiency of the turbine engine.

A troubleshooting chart provides information about common or frequently occurring troubles in a unit, their cause, and remedies. It is a useful resource for identifying and resolving issues that may arise during the operation or maintenance of the unit. Historical records may provide some information about past troubles, but they may not be comprehensive or up-to-date. Maintenance records primarily focus on the maintenance activities performed on the unit and may not provide detailed troubleshooting information. An illustrated parts breakdown is a visual representation of the unit's components and may not include troubleshooting details. Therefore, a troubleshooting chart is the most appropriate source for finding information about common troubles, their cause, and remedies.

The portable load bank can apply a maximum AC resistive load of 75 kilowatts to a generator.

The oil pressure switch is responsible for monitoring the oil pressure in the A/M32A-60A. If the switch opens at any point during operation, it will stop the operation of the A/M32A-60A. This means that regardless of the operating period, whether it is from 0-35 percent, 35-95 percent, or 95-100 percent, if the oil pressure switch opens, the operation will be halted. Therefore, the correct answer is "Anytime during operation."

The vent system is responsible for removing oil vapors from the turbine engine. This system is designed to release any excess pressure and gases that may build up within the engine. By venting these vapors, the system helps to maintain proper functioning and prevent damage to the engine. The cooling fan, suction pump, and oil jet assembly are not directly involved in the removal of oil vapors from the turbine engine.

The correct answer is a decrease in vibration after 35 percent. This means that as the GTC accelerates, the level of vibration experienced by the vehicle decreases after it reaches 35 percent of its acceleration. This characteristic suggests that the GTC provides a smoother and more comfortable ride as it gains speed.

The weak points of a self-excited AC generator are the brushes, slip rings, and commutator. These components are prone to wear and tear over time, leading to decreased efficiency and potential malfunctioning of the generator. The brushes make contact with the commutator, which rotates with the rotor, allowing the electrical current to flow. However, the brushes and commutator can wear down due to friction, resulting in poor contact and electrical resistance. Similarly, the slip rings, which provide a continuous connection between the rotor and external circuit, can also wear down and cause issues with the generator's performance.

After the A/M32A-60A generator set has reached 95 percent of governed speed, the operator should reset the AC system. This is because reaching 95 percent of governed speed indicates that the generator set is operating at its desired speed. Resetting the AC system ensures that any previous settings or errors are cleared and the system is ready to operate efficiently. It allows for a fresh start and ensures that the AC system is functioning properly.

Before using the EPU-6/E frequency converter, it is necessary to inspect the air inlets for blockage. This is important because if the air inlets are blocked, it can restrict the flow of air into the converter, leading to overheating and potential damage. By ensuring that the air inlets are clear and free from any obstructions, proper airflow can be maintained, allowing the converter to function efficiently and effectively.

In a series-wound DC motor, the speed is controlled by the load. This means that the speed of the motor is influenced by the amount of mechanical resistance or load that is connected to it. As the load increases, the motor's speed decreases, and vice versa. The load torque directly affects the motor's speed by opposing or assisting the rotation of the armature. The field winding, on the other hand, is responsible for creating the magnetic field within the motor but does not directly control the speed.

The capacitive-start induction motor has the highest starting torque compared to the other options. This is because it uses a capacitor in the starting winding to create a phase shift between the main and starting windings, resulting in a higher starting torque. The squirrel cage, shaded pole, and split-phase induction motors have lower starting torques in comparison.

When checking the concentricity of a commutator or slip rings, it is important to look for roundness. This means that the shape of the commutator or slip rings should be circular and not distorted or irregular in any way. Roundness is crucial for the proper functioning of the commutator or slip rings as it ensures smooth contact and transfer of electrical current. If there is any deviation from roundness, it can lead to issues such as poor electrical conductivity, increased friction, and potential damage to the components. Therefore, roundness is a key factor to consider when inspecting the concentricity of a commutator or slip rings.

A blower is installed on a two-stroke diesel engine to ensure the displacement of all exhaust gases. The blower helps in creating positive pressure in the cylinder, which helps in pushing out the exhaust gases and bringing in fresh air for the next combustion cycle. This ensures that all the exhaust gases are effectively removed from the cylinder, allowing for better engine performance and efficiency.

The resistive elements on the A/M24T-8 test set are best cleaned by blowing off with 5 psi uncontaminated air. This method is effective in removing any dust or debris that may have accumulated on the resistive elements. Steam cleaning or scrubbing with soap and water may not be suitable as they can introduce moisture or contaminants that could damage the test set. Blowing off with 15 psi uncontaminated air may be too high of a pressure and could potentially cause damage to the resistive elements. Therefore, blowing off with 5 psi uncontaminated air is the most appropriate and effective method for cleaning the resistive elements.