Control Systems Page 37-38 Flashcards
Describe a single element temperature control for a large lubricating oil system.
Lube oil from the sump of the main engine is circulated around the system to maintain the correct temperature. The control module compares the oil temperature at the suction of the sump and the inlet of the engine to the set point. If too hot, the 3-way valve opens to pass through the cooler; if the temperature is correct, it bypasses the cooler and goes straight to the main engine inlet.
What components are involved in the single element temperature control system?
The components include a control module, output signal, actuator, set point input, 3-way valve, circulation pump, and cooler.
Describe a method of remotely monitoring the contents of a fuel oil tank.
Level Pressure Transmitters gauge the tank by measuring hydrostatic pressure applied on the transmitter. The pressure is converted into an electrical signal through the deformation of the sensor diaphragm, which changes the electrical resistance.
What components are involved in the fuel oil tank monitoring system?
The components include a basic tank level gauge, fuel tank, pressure diaphragm, and an electrical signal output showing tank level.
- Describe with the aid of a sketch, a single element temperature control for a large lubricating oil system (16)
- Describe with the aid of a sketch, a single element temperature control for a large lubricating oil system (16)
Description:-
Lube oil from sump of M.E is circulated around system where it is maintained at correct
temperature. This is achieved as the oil at the suction of sump & inlet of engine is compared to
the set point. The control module senses this and either opens the 3-wayvalve to pass through
cooler if too hot or bypass the cooler and go straight to the main engine inlet if the temperature
is correct
- Describe, with the aid of a sketch, a method of remotely monitoring the contents of a fuel oil tank (16)
Description:-
The Level Pressure Transmitters are performing tank gauging by hydrostatic pressure that is applied on the transmitter.
The direct conversion of the pressure into electrical signal is achieved by a minute deformation of the sensor diaphragm with applied pressure which changes the electrical resistance.
- Describe, with the aid of a sketch, a method of remotely monitoring the contents of a fuel oil tank (16)
What are four examples of a measured variable in a control system?
Temperature, Electrical Voltage, Flow Rate, Pressure
What is the basic action of a two-step controller?
The two-step controller output signal changes from one predetermined value to another when the deviation of the measured variable changes.
This is not the same as ON-OFF control especially in digital systems.
What is the basic action of a proportional controller?
The proportional control acts to maintain the output variable near constant by adjusting the process proportionate to the deviational value, with the smallest possible offset.
