Controls - Part B Flashcards
The three (3) primary reasons for sensing and measuring variables are to __________, __________, and __________.
Indicate, record, and control
The four (4) main types of measured variables are __________, __________, __________, and __________.
Temperature, pressure, liquid level, and flow rate
To protect thermometers and other sensing bulbs from high external pressures and possible damage, __________ are installed in pressure vessels and pipe.
Thermowells
The __________ __________ __________ produces a longer scale of measurement than other types, so a more accurate reading can be taken.
Inclined tube manometer
__________ or __________ to be applied to the gauge is connected to the housing that encloses the diaphragm.
Pressure or vacuum
As a result, the __________ rises and falls with the liquid level, and this movement can be used to operate a control valve.
Float
An __________ __________ is the most common form of restriction used to measure flow.
Orifice plate
The term __________ __________ is explained as the point where the area is at a minimum size; therefore, the fluid is at its highest velocity and lowest pressure
Vena contracta
__________ __________ sense impact and static pressure at the same instant.
Pitot tubes
On small systems, a __________ __________ __________ located in the compressor room supplies reduced pressure to the entire control system.
Pressure reducing station
The __________ __________ is to prevent dust or other airborne contaminants from entering the intake valves of the compressor.
Intake filter
The compressor oil must be the type recommended by the __________ to maintain the life of the compressor and the warranty.
Manufacturer
Limiting __________ in compressed air piping is of the utmost importance.
Condensation
Another type of dryer involves the use of __________, or chemicals, to remove moisture from the control air.
Desiccant
The __________ __________ is located in the piping between the compressor and the pressure reducing valve.
Moisture condenser
The ___________ ___________ has been decreased in the system, thereby reducing the amount of water deposited throughout the system.
Air temperature
Pneumatic controls are separated between ___________ and ___________ type control systems
HVAC and process
The ___________ ___________ located on the outside wall at the ground floor would make maintenance and future renovations more accessible.
Compressor room
For all pneumatic instrumentation systems, the ___________ ___________ ___________ is the major organization that writes and issues standards.
International Society of Automation
A ___________ ___________ that has a ___________ float must react at the correct elevation to maintain the function of the process.
Level meter, float
Precautions should be made when working moving equipment; ___________ and ___________ procedures should be followed.
Tag and lockout
When working on plant sites, follow the ___________ ___________ and ___________ ___________. Generally the industry plants exceed the OH&S rules and they must be followed.
Written regulations and safety rules
Consult the ___________ for relevant information on the material in the process lines.
MSDS
When troubleshooting the sensing and measuring variables, you should be primarily concerned with the:
Primary element
When a pressure gauge is located on the process piping, it is classified as:
Integral mounted
A thermometer is really designed to measure:
Molecular movement
The sensing element normally used in a pressure gauge is a:
Bourdon tube
The thermoelectric pyrometer temperature uses:
DC millivolts
Floats can control, indicate, or record events; this liquid level device is based on the laws of:
Buoyancy laws
The only type of flow measuring device that accurately measures volume is the:
Positive displacement type
When installing an orifice plate between a pair of orifice flanges, the stamped face is normally installed:
Upstream of the flow
Which flow sensing device will handle more flow with less pressure drop?
Pitot tubes
The type of meter that is mainly used as an indicating device is the:
Rota meter
Moisture is introduced into the pneumatic control system from the:
Intake filter
The air compressor is controlled by a:
Pressure switch
The aftercooler is located:
Before the receiver
Lubrication should remain in the:
Compressor
The type of air drying technique that uses a cooling tower is a:
Moisture condenser
The building type that would require the most rigid HVAC standards is a:
Hospital
The primary noises transmitted from the compressor are caused by:
Vibration
The type of piping or tubing found on large pneumatic instrumentation systems is:
Galvanized pipe
Before filling and testing a system that contains float type meters, you should:
Install plugs
Each control valve should have an:
ID tag
