2A672 Volume 2 Ure Frequesncy Converter

Prior to use, it is important to inspect the air inlets for blockage in the EPU-6/E frequency converter. This is because blocked air inlets can restrict the flow of air into the converter, leading to overheating and potential damage. By checking the air inlets for blockage, any obstructions can be cleared, ensuring proper airflow and preventing any potential issues.

If the exhaust door is not opened and secured, the -95 will not be able to start. This is because the exhaust door allows the release of exhaust gases from the turbine. If it is closed or not properly secured, the exhaust gases will not be able to escape, which can cause a buildup of pressure and prevent the turbine from starting. Therefore, opening and securing the exhaust door is a crucial preliminary step in the set-up process to ensure the -95 can start successfully.

During the operation of the EPU-6/E frequency converter, it is determined that the E and F pin voltage is not needed for the aircraft. In this scenario, the operator should place the Loop/bypass/28 V to aircraft switch in the "Bypass" position. This allows the voltage to bypass the E and F pins and directly supply the aircraft with the 28 V power it requires.

The deswirl ring on the -95 gas turbine compressor is responsible for smoothing turbulent air flow. Turbulence in the air flow can cause inefficiencies and disruptions in the compressor's operation. The deswirl ring helps to eliminate or reduce these disturbances, ensuring a smoother and more controlled airflow. This allows for better performance and efficiency of the compressor, ultimately improving the overall functioning of the gas turbine.

Inward leaks occur in a refrigeration system when the pressure within the system is less than atmospheric pressure. This means that air or other substances from the outside are being drawn into the system, causing a decrease in pressure. These leaks can lead to a loss of refrigerant and a decrease in the system's efficiency.

Bubbles in an air conditioner refrigeration system sight glass probably indicate a low refrigerant charge. When there is a low refrigerant charge, the system does not have enough refrigerant to properly cool the air. This can cause the refrigerant to boil and create bubbles in the sight glass. It is important to have the correct amount of refrigerant in the system to ensure efficient and effective cooling.

The correct answer is nothing, this is normal operation; the blower clutch energizes at governed speed. In this scenario, the engine on the air conditioner is operating at 1,250 rpm, but the blower clutch does not engage. However, this is considered normal operation as the blower clutch energizes at governed speed, which means it will only engage at a certain predetermined speed set by the system. Therefore, there is no need to replace any components or check the MPU signal in this case.

The interstage seal is the correct answer because it is a component that separates the second-stage air from the operation of the first-stage compressor. This seal ensures that the air from the first-stage compressor does not mix with the air from the second-stage, allowing for efficient and controlled compression in each stage. The interstage seal helps maintain the integrity and performance of both stages of the compressor.

The ACE 802S air conditioner uses an air engine starter.

The probable cause of the trouble is the battery charging module. This module is responsible for regulating the charging rate of the battery. If it is not functioning properly, it may not shut down the -95 when the charging rate decreases to 12 amperes.

The control transformer on the EPU-6/E frequency converter provides 120 VAC for the operation of the E and F line 28 VDC power supply. This means that the transformer converts the incoming voltage to 120 VAC, which is then used to power the E and F line 28 VDC power supply. This voltage is necessary for the proper functioning of the power supply, allowing it to provide the required 28 VDC power to the aircraft contactor.

The oil tank vent line prevents overpressurization of the bearing cavity on a -95. This is because the vent line allows excess pressure to escape from the oil tank, preventing it from building up and causing overpressurization.

A loose push-on connector on the output filter capacitor could cause one phase voltage to be lower than the other two phases. When the connector is loose, it can result in a poor connection and create an imbalance in the voltage distribution. This can lead to lower voltage in one phase compared to the others.

When the butterfly valve is closed, chambers 1, 3, and 4 are pressurized.

At 100 percent engine speed, the discharge air pressure on the -95 should indicate 35 +2 psig.

When the ACE 802S compressor is in the HOLD position, the compressor displacement remains constant. This means that the volume of air compressed by the compressor remains the same, regardless of any external factors or changes in operating conditions. The compressor does not vary its displacement while in the HOLD position, ensuring a consistent output of compressed air.

The correct answer is that the analog board has failed. This means that there is an issue with the analog board, which is responsible for converting analog signals into digital signals. This malfunction could be causing the undervoltage fault problem with the EPU-6/E frequency converter unit.

The oil pressure switch is the component that closes to complete the electrical circuit to the fuel solenoid and ignition unit. This switch is designed to monitor the oil pressure in the engine. When the oil pressure reaches a certain level, the switch closes, allowing the electrical current to flow and activate the fuel solenoid and ignition unit. This ensures that the engine has sufficient oil pressure before allowing the fuel and ignition systems to operate, which is crucial for the safe and efficient functioning of the engine.

When heat is applied to an ice cube and it starts to melt, the process is known as latent heat. Latent heat refers to the heat energy absorbed or released during a phase change, such as melting or vaporization, without a change in temperature. In this case, the ice cube absorbs heat energy from its surroundings, causing the solid ice to change into liquid water. This absorption of heat energy is known as latent heat because it is not causing a change in temperature, but rather a change in the state of matter.

The correct answer is conduction, convection, and radiation. These three methods of heat transfer are fundamental concepts in thermodynamics. Conduction is the transfer of heat through direct contact between objects or materials. Convection is the transfer of heat through the movement of fluids or gases. Radiation is the transfer of heat through electromagnetic waves, such as infrared radiation. These three methods play a crucial role in various natural and technological processes, and understanding them is essential in fields like engineering, physics, and meteorology.

The SCR voltage regulator and phase sequence transformer receive potential directly from the input auto transformer.

The air flowing through an air conditioner is commonly referred to as the "heat load" because it carries the heat from the indoor space to be removed or cooled by the air conditioning system. The heat load is the amount of heat energy that needs to be transferred or removed from the space to maintain a desired temperature. It is an important factor in determining the capacity and efficiency of an air conditioning system.

The probable cause of the engine not operating when the MA-3D air conditioner SW1 is placed in the START position is that the override switch is not closed.

The correct answer is the Input auto transformer. The input auto transformer is responsible for providing 525 VAC to the control transformer of the EPU-6/E frequency converter. This component helps in regulating and transforming the voltage from the input power source to the desired level for the control transformer. It plays a crucial role in ensuring the proper functioning of the frequency converter by supplying the necessary voltage to the control transformer.

When the output air temperature of the MA-3D air conditioner is too high, setting the temperature control to maximum cooling is the appropriate action to take. In this scenario, the temperature controller sends a signal to B7, which steps open to meter R134a into the evaporator. This means that B7 opens up to allow R134a refrigerant to enter the evaporator, which aids in cooling the air.

The correct answer is the compressor section. In a gas turbine, the compressor section is responsible for supplying high-volume, low-pressure air for various purposes such as combustion, cooling, and bleed air output. It compresses the incoming air, increasing its pressure before it enters the combustion chamber. This section plays a crucial role in the overall functioning of the gas turbine by ensuring the proper flow and pressure of air for combustion and other necessary operations.

Fuel is used to lubricate the engine starter on the ACE 802S air conditioner. Fuel is essential for the engine to start and run smoothly. It acts as a lubricant for the moving parts of the engine, reducing friction and preventing wear and tear. Without fuel, the engine starter would not be able to function properly, leading to difficulties in starting the air conditioner. Therefore, fuel is the correct medium for lubricating the engine starter on the ACE 802S air conditioner.

The correct answer is 2 because the rate-metering valve on the -95 prevents the butterfly valve from snapping open. This is achieved by bleeding air through the atmospheric bleed port from the chamber.

When engaging the compressor on the ACE 802S, holding the compressor switch in the HOLD position allows the oil and discharge pressures to stabilize. This is important because the compressor needs stable pressure levels for proper operation. By holding the switch in the HOLD position, it ensures that the pressures have reached a stable state before fully engaging the compressor.

The correct answer is suction pressure is too low so the boiling point of the refrigerant must be increased to increase the output air temperature. When the suction pressure is too low, it means that there is not enough refrigerant entering the compressor. This can result in a decrease in the output air temperature. To compensate for this, the temperature controller opens the hot gas bypass valve, which increases the boiling point of the refrigerant. By increasing the boiling point, the temperature of the refrigerant increases, which in turn increases the output air temperature.

The air load switch energizes SV4 according to foldout 2.

Short cycling in an air conditioner refers to the unit turning on and off frequently, which can be caused by various issues. Checking the receiver outlet valve is a valid step to take in order to correct this trouble. The receiver outlet valve controls the flow of refrigerant from the receiver to the evaporator, and if it is malfunctioning or blocked, it can cause the unit to short cycle. By checking the valve, one can identify and address any issues with it, potentially resolving the problem of short cycling.

The electric expansion valve is the component that controls the flow of refrigerant into the evaporator in an MA-3D air conditioner. It is responsible for regulating the amount of refrigerant that enters the evaporator coil, ensuring optimal cooling efficiency. By opening and closing, the electric expansion valve adjusts the flow rate based on the cooling demand, maintaining a consistent temperature in the evaporator and preventing the system from freezing or overheating.

During an ops check of a -95, when the air load switch S2 is placed in the ON position, the butterfly valve starts to open at 95 percent. In this scenario, you would check TD2.

The probable cause of this trouble is that K3 de-energized and its contacts did not remain closed. This means that the circuit that charges the battery is not able to complete, resulting in the battery not charging.

The probable cause of the engine cranking but not starting is that the SV1 coil is open. An open coil means that there is a break in the electrical circuit, preventing the coil from receiving power and functioning properly. Without the coil functioning, the necessary spark to ignite the fuel mixture in the engine cannot be generated, resulting in the engine failing to start.

The power monitor relay (PMR) component of the MA-3D air conditioner provides 24 VAC for operation of the temperature controller. This means that the PMR is responsible for supplying the necessary electrical power to the temperature controller, allowing it to function properly. The generator (G1) and alternator (G2) are unlikely to provide the specific voltage required for the temperature controller, while the transformer rectifier (TR1) is not mentioned in relation to providing power for the temperature controller. Therefore, the correct answer is the power monitor relay (PMR).

The relay K8 prevents the MA-3D air conditioner pumpdown light from illuminating in the cool mode.

The temperature controller (TC) is responsible for monitoring the temperature and maintaining it within a specific range. In the case of the MA-3D air conditioner, when the temperature exceeds the desired limit, the TC breaks the circuit to K2, which in turn de-energizes the compressor clutch. This action prevents the compressor from running and helps to ensure the safety of the air conditioning system.

To troubleshoot the issue of the MA-3D air conditioner radiator fan not operating, you should start by checking K4. This suggests that K4 is a component or a connection point related to the operation of the fan. By inspecting K4, you can identify any potential faults or malfunctions that may be causing the fan to stop operating.