ELECTRIFICATION Flashcards
This refers to the part of the control system to be controlled or monitored, it can also be referred to as a process.
PLANT
Certain books refer to this term as (the controlled output CO) and is defined as the signal of interest, the desired result to be obtained from the system.
OUTPUT
A physical interconnection of devices that influences the behavior of other devices or systems.
ELECTRICAL CONTROL SYSTEM
A physical interconnection of devices that influences the behavior of other devices or systems.
ELECTRICAL CONTROL SYSTEM
This can either be a device inside the system or outside the system which regulates the plant or the process. –
CONTROLLER
This is the signal injected into the system from an external energy source. It is majorly referred to as the reference input.
– INPUT
This can be seen as an alien symbol, which can be generated either externally or internally that affects the system in a negative manner. –
DISTURBANCE
System where one in which the output does not feedback to the input to correct variations.
– OPEN LOOP CONTROL SYSTEM
System where one in which the output has an effect upon the input to maintain a desired output value. –
CLOSED LOOP CONTROL SYSTEM
Types of control where the system uses no automatic controls, the link is provided by the human operator. –
MANUAL CONTROL
Types of control where the sequence of operations is carried out automatically after being started by a human operator. –
SEMI-AUTOMATIC CONTROL
Types of control where the human operator is replaced by a controller which monitors the system in comparison with a desired value, using feedback loops to take corrective action if necessary. –
AUTOMATIC CONTROL
Types of control where a level, hand wheel or other attachment fixed on the unit ‘locally’ is used as a means of alteration and control.
– LOCAL CONTROL
Types of control where the regulating unit is connected to an actuating device mounted some distance away by means of power transmission through electrical linkages.
– REMOTE CONTROL
Types of control where the regulating unit can occupy only one of the two available positions of ‘on’ or ‘off’. –
ON/OFF CONTROL
Types of control where more than two positions can be occupied by the regulating unit but the action occurs in steps rather than being continuous. –
STEP-BY-STEP CONTROL
Factor in selecting electric motor where electricity may be direct current (d.c) or alternating (a.c). It may be one of the several voltages. –
TYPE OF ELECTRIC POWER AVAILABLE
Part of a motor where is consists of a slotted core, made up of thin sections of a special soft steel, exercise pet squirrels –
ROTOR
Part of a motor where is consists of a slotted core also made of special laminated steel. Insulated copper wire is wound in the slots in such a way as to form one or more pairs of definite magnetic poles. –
STATOR
type of motor where motor consists of a squirrel-cage rotor and a stator in which are found two different sets of windings. –
SPLIT-PHASE
A Type of motor where motor will operate an either direct or alternating current of the correct voltage –
UNIVERSAL MOTORS
A Type of motor where the direction of rotation of a determined by the way the three line wires are connected to the motor. Interchanging the connections of any two line leads will cause the motor to rotate in the opposite direction, so reversing is a very simple process. –
THREE-PHASE MOTORS
A Characteristic of a Good Electrical System where there are grounding, proper size of conductors and ratings of circuit breakers. –
SAFE
A Characteristic of a Good Electrical System where the design is ready for future expansion. –
EXPANDABLE
A Characteristic of a Good Electrical System where the one that fulfills its needs at the least expense over the lifetime of the system. –
EFFICIENT
Type of grounding where it can be a grounding electrode or any conductive material connected directly or indirectly to earth –
EQUIPMENT GROUNDING
Type of grounding where the main function is to prevent electric shock to persons or animals coming in contact with metallic objects, which themselves have come in contact with a hot conductor due to some electric fault –
EQUIPMENT GROUNDING
electrons at the outermost shell, farthest from the nucleus
valence electrons
rate of charge flow past a given point in an electric circuit
current
the work required to move a unit charge from one location to another
voltage
the relative difficulty with which current can be transmitted in a material
resistance
most conductors ____ in resistance with an increase in temperature
increase
components are connected end-to-end in a line to form a single path for electrons to flow
series circuit
all components are connected between the same set of electrically common points
parallel circuit
AC stands for____
altenating current
this is the basic operating principle of an AC generator
alternator
has the ability to step voltage up or step voltage down from the powered coil to the unpowered coil
transformer
primary winding has more turns than the secondary
step-down transformer
the primary winding has fewer turns than the secondary
step-up transformer
when an alternator produces AC voltage, the voltage switches polarity over time, but does so in a very particular manner
AC waveforms
____ is where two or more waveforms are out of step with each other
phase shift
is defined as one waveform that is ahead of another in its evolution
leading waveform
is a mathematical quantity representing 2 dimensions of magnitude and direction
complex number
is a graphical representation of a complex number
vector
is used in electrical applications where the angle of the vector represents phase shift between waveforms
phasor
length of a vector represents the ____ of the wave
amplitude
angle of a vector represents the ____ of the wave
phase angle
is the opposition that an inductor offers to alternating current due to its phase-shifted storage and release of energy in its magnetic field
inductive reactance
SORI SA MGA TYPO MGA MADIIII
AMEN
the total measure of opposition to electric current and is the complex (vector) sum of (real) resistance and (imaginary) reactance
impedance
power dissipated by a load
true power
power merely absorbed and returned in load due to its reactive properties is referred to as ___
reactive power
total power in an AC circuit, both dissipated and absorbed/returned
apparent power
- 2000 years ago, they realized you could create a charge by rubbing two things
- discovered electric charges
ancient greeks
is simply the flow of electrons from one place to another
electricity
moves very easily through metal wire
electron
works by producing mechanical energy using an engine, which can be powered using a variety of fuel option such as diesel
generator
used to create mechanical energy
engine
created the electrical output form the engine generated mechanical energy
alternator (genhead)
is a piece of portable equipment, consisting of an engine and an alternator/electric generator, used to provide energy
generator set (genset)
a combination of prime over, and an alternator
genset
converts the chemical energy of a fuel to mechanical energy
engine
uses the sun energy to either boil water or directly converts solar energy to electrical energy
solar
solid-state devices that convert sunlight directly into electricity
Photovoltaic (PV) Modules
building blocks of PV modules made of semiconductor materials
PV cells
when light strikes a PV cell, it imparts energy to some electrons to free them
PV effect
adding atoms with different number of electrons to create an unbalanced number of electrons to the base material
doping
commonly termed as wind turbines or windmills
wind machines
- rotor axis of rotation is in line with the prevailing wind direction
- also called directional windmill type
horizontal axis turbines
continuously orients the rotor in the direction of the wind (yawing)
yaw control
the turbine, the electrical generator, and the entire system is designed to withstand the extreme speed under gusty wind
no speed control
the rotor axis is shifted out of the wind direction when the wind speed exceeds the design limit
yaw and tilt control
changes the pitch of the blade with the changing wind speed to regulate the rotor speed (PITCHING)
pitch control
when the wind speed exceeds the safe limit on the system, the blades are shifted into a position such that they stall
stall control
has lower heat value but has higher octane rating than gasoline (higher engine efficiency with higher compression ratio)
ethanol
–synthesizes from biomass pyrolysis gas
–can also be processed from natural gas
–can be used as an alternative fuel to gasoline
methanol
is used to convert the wave motion into power
wave power device
national highway of electricity delivery
transmission
a form of radiant energy from natural sources and artificial sources
light
application of light to illuminate objects, surfaces, scenes, pictures
lighting
rays of light enter the eye through __
cornea
a measure of how much flux is emitted within a small conical angle in the direction of the surface
luminous intensity
a physical interconnection of devices that influences the behavior of other devices or systems
electrical control system
is the ‘cause’ of the change in the process or system operation
input signal
is the ‘effect’, the consequence of the cause
output signal
Is ensured by the insulation of all life parts to prevent from a direct contact
basic protection
Is ensured by simply placing electrical circuits and installations out of reach and by prevention of direct contact through enclosures, barriers or covers and housing.
direct protection
use to house the overcurrent devices
panel board
are installed in series with the hot conductors and are designed to open the circuit if a specified current level is exceeded
Overcurrent protective devices
overcurrent devices of which a portion is destroyed when interrupting the circuit
fuses
allow higher temporary overcurrent during motor starting
time-delay fuse
device designed to open a circuit automatically at a predetermined overload current without damage to itself
circuit breaker
–connecting directly or indirectly to earth
–main fxn: safety
grounding