Electrical Layout and Estimate Flashcards
1
Q
Is a form of energy generated by friction, induction or chemical change, having magnetic, chemical and radiant effect.
A
Electricity
2
Q
Electrons in Motion
A
Electricity
3
Q
date when electricity was accidentally discovered by Greeks.
A
600 BC
4
Q
He is an english physicist, considered Father of Electricity, after publishing his studies on Electric Attraction and The Electric Force
A
William Gilbert
5
Q
Electricity consists of (3):
A
Electrons
Neutron
Proton
6
Q
The ___ is the negtaively charged particle of an Atom sometimes referred to as the negative charge of electricity.
A
Electron
7
Q
On the other hand, the ____ is the positively charged particle of an Atom which is sometimes referred to as the positive charge of electricity that weighs about 1850 times as much as the Electron.
A
Proton
8
Q
____ is that particle of an Atom which is not electrically charged and weighs slightly more than the proton.
A
Neutron
9
Q
Is the term applied to an atom or molecule which is not electrically balanced. It is an atom or molecule that is electrically cahrged. It simply mean there is a loss or gain of one or more electrons. It occur when the electrons in the atom is loosened through friction by another atom. Therefore, the presence of electrons in any organic or inorganic substance is a fact, that electricity is always present.
A
Ion
10
Q
Volt or voltage is the electrical pressure that causes the electrons to move theough a conductor (wire). It is an Electromotive FOrce
A
Volt or Voltage
Comparatively, to have 12 volts is like having 12 pounds of water pressure inside the pipe of a water system. Thusm the higher the voltage, the more electricity will be forced to flow.
11
Q
Volt was named after this Italian scientist who discovered that electrons flow when two different metals are connected by a wire and then dipped into a liquid that conduct or carry electrons.
A
Alessandro Volta
12
Q
Is the standard unit used in measuring the strength of an electric currrent, named after Andre M Ampere.
A
Ampere
13
Q
It is the amount of current flow, sent by one volt through the resistance of one Ohm,. When there is too mush flow of electricity in a small conductor or wire, heat is produced which eventually may blow-off the protective devise called fuse, or burn the wire insulator and create fire.
A
Ampere
14
Q
Watt is name after _____, a scottish inventor.
A
James Watt
15
Q
Is the rate or measure of power used or consumed. It represents the equivalent heat volts and ampere consumed by lights, appliancces or motors.
A
Watt
16
Q
Refers to the wire installations that supply current to light and convenient outlets.
A
Circuit
17
Q
IS the firction or opposition to the flow of current by the wires and transformers, analogous to plumbing installation, where the flow of water is subjected to resistance caused by friction between the water and the inside wall of the pipe, and the various form of turns and fittings.
A
Resistance
18
Q
For direct current (DC), friction is ______
A
Resistance
19
Q
For alternating current (AC), friction is ______.
A
Impedance
20
Q
Factors that influences Conductor Resistnace. (4)
A
Composition of the conductor
Length of wire
Cross sectional area of wire (eg the bigger the section the lower the resistance)
Temperature
21
Q
is the flow or rate of flow of electric force in a conductor.
A
Electric Current
22
Q
Types of Electric Current
A
DC
AC
23
Q
flows in one direction, the flow is said to be from negative to positive, a dry cell or storage battery.
A
DC
24
Q
Constantly reverses its direction of flow, it is generated by machine called generator, this type of current is universally accepted because of its unlimited number of applications with the following advantages.
Easily produce
cheaper
it can be transformed to higher voltage and drop it to low voltage
more efficient compared to DC
A
Alternating Current
25
who advocates the DC
Thomas Edison
26
who advocates the AC
George Westinghouse
27
The AC current goes through one positive loop and one negative loop to form one complete cycle that is continuously repeated.
The number of times this cycle of plus and minus loop occur per second is called the _____ expressed in cycles per second normally referred to as Hertz.
Frequency of Alternating Current
28
The hertz is named after German physicist \_\_\_
Heinrich Hertz
29
Frequency of DC is \_\_\_
Zero
30
unit of Resistance
OHMS
31
The higher the Voltage, the ___ the Current.
Larger
| (direct proportional)
32
The higher the resistance, the ____ the current.
Lower
| (inversely proportional)
33
Ohms law formula for DC:
I = V/R
whre
I = current
V = voltage
R = resistance for DC electricity
34
Ohms law for AC:
I=V/Z
where
I - Current
V= Voltage
Z= impedance
35
unit of Current
Ampere (A), amp
36
Under the principles of DC electricity. Power is the product of voltage and current.
Watts = Volts x Amperes
37
Under the principle of AC electricity, the product of volts and amperes is equal to the quantity called volt-ampere (va) which is not the same as watts, thus:
Volt Amperes = Volts x Amperes
38
To convert volt-ampere to watts or pwoer, a power factor (pf) is introduced, and to get power in an AC circuit, we have the following formula:
Watts = Volts x Amperes x power factor
W=V x I x pf
39
A 12 amperes electric fan and blower with a power of 0.85 was connected to a 240 volts convenient outlet (CO). Calculate the current and power in the circuit
W = 240v x 12 amp x 0.85
W = 2,448 watts
40
An electric motor has a trade mark label of 2 horse power, 240 volts, 15 amperes,. Calculate the motor power factor.
Assume motor efficiency say 85%
1 HP is equal to 746 watts,
746 x 2 = 1492 watts
Efficientcy = 1492/85
1755 watts
For AC Current:
power = volts x amperes x power factor
power factor = (power/volts x amperes)
pf = 1755 / 240 x 15amp
pf = .4875
Volt-Amperes = 240 v x 25
Volt Amperes = 3600 va
41
The higher the voltage, the larger the current, and the higher the resistance, the lower the current.
Ohms Law
42
In 1962, ____ a german scientist, discovered the relationship between the Current, Voltage and resistance now referred to as the OHms Law.
George Simon Ohm
43
Ohms Law formula:
I = V/R
where
I = current (ampere)
V= electromotive formce (volts)
R = resistance (ohms)
44
Determine the current flow in a circuit having a resistance of 5 ohms on a 120 volts and 240 volts current supple. (circuit refers to electrical wiring installation.
For 120 Volts
I=V/R=120/5
I = 24 amperes
For 240 Volts
I = V/R = 240/5
I = 48 Amperes
It can be conclueded from the foregoing illustrations that a 240 volts circuit is better choice than using a 120 volt circuit as computed with 48 and 24 amperes respectively.
45
Power =\_\_\_\_
Voltage x Ampere
46
Two types of circuit
Parallel Circuit
Series Circuit
47
A single path exist for current flow, that is, the elements are arranged in a series on after the other with no branches. Being a single path in a seriesarrangement and resistance simply adds.
Series Connection
Voltage Total = V1 + V2 + V3
Resistance Total = R1 + R2 + R3
48
Two Automobile headlights are connected in a series to a 12 volts battery each having a resistance of 1 ohm. What is the current flowing in the circuit?
V = 12volts
Total resistance = R = r1 + r2
I= v/r
= 12v/2
I = 6 amperes
49
Another example of a series connection is the _____ having a single wire supplying the current. When a single bulb breaks off, the flow of current is also cut off, putting the entire series of light into total darkness.
String of Christmas Light
50
The parallel circuit is sometimes referred to as ____ where the loads are placed across the same voltageconstituting a separate circuit
Multiple Connections
51
\_\_\_ is the standard arrangement for house wiring connections wherein the lights constitute one parallel grouping and the convenience wall outlets constitute the second parallel grouping.
Parallel CIrcuit
52
The fundamental principle under this type of circuitry is that "loads in parallel are ____ for current, and that each has the ___ voltage.
additive
same
53
Ohms Law
AS resitance increases, current decreases. When current rises instantly to a very high level, the condition will constitute a \_\_\_\_. Hence, it is mandatory for all circuit to be protected by fuse or circuit breaker that automatically open and disable the line in case of a fault or short circuit.
Short Circuit
54
\_\_\_\_\_ is a simple static device consisting of a magnetic core wherein the primary and secondary windings are made. The voltage is directly proportional to the number of windings or turns. Thus, if a 120 AC will be connected to the left side containing 100 turns, 240 volts would be on the right side containing 200 turns.
Transformer
55
\_\_ is the technical term for the common word work.
POwer
56
\_\_\_ is the product of power and time expressed in the following equiation:
ENergy or Work= Power x time
Work
57
In electrical terms, energy is synonymous with \_\_\_.
Fuel
58
\_\_\_ is expressed in units of BTU (calories), foot pound (joules) or kilowatt hour.
Energy
59
Under the english unit system, the unit of power is expressed in "\_\_\_\_(3).
Horse power, BTU per hour, watt and kilowatt
60
Under the Metric system or SI, it is correspondingly expressed as ____ (3)
Joules per second, calories per second, watts and kilowatts
61
In physical terms, ___ is also the rate at which fuel or energy is used and expressed as liters of fuel per hour, cubic meter of gas per minute or tons of coal per day. etc.
Power
62
The measuring unit of electric power is the \_\_\_
Watt
63
1kW =
1000watts
64
Derivation of W= VI
Watt = I2 x R
Ohms Law:
V = IR
since W = I2 R
W = VI
where.
W=watts
R=Ohms
I=Amperes
V=Volts
65
A mercury lamp having a hot resistance of 50 ohms, is connected to a socket with 240 volts current supply.\
a. How much current, flows through the lamp?
b. calculate the power drawn
I = V/R;
I = 240/500:
I = 4.8 amperes
Where power factor (pf) in a purely resistive circuit, such as those with only electric heating elements, impedance or resistance power factor (pf) is equal to 1. Thus
W= VI x pf
= 240 x 4.8 x 1
= 1152 watts
=I2R
= (4.8)2 x 50
= 1152 watts
66
Determine the monthyly energy consumption of the following appliance:
Water Heater; Load of 1000 watts, daily used of 3 hours
1000 = 1kW x 3 hrs = 3kwh
If the average cost of energy (not power) is t.00 per kwh for 30 days consumption, multiply:
30 x 3 = 90kwh x 5.00
450 pesos
67
In a series circuit - ___ is the same throughout but ___ differs.
Current
Voltage
68
In a parallel circuit, the __ is the same but the ___ differs.
voltage
current
69
Take note that in a ___ arrangement, all current loads cumulatively add. For instance, appliances and light loads connected to a parallel circuit has the same voltage imposed, but each load draws a different current according to its wattage rating.
Parallel
70
The power loss in the conductor wire is transformed into heat. COmparatively, a 1200 watts appliance rating has 10 amperes current flow on a 120 volts current supply compared to 5 amperes only on a 240 volts current supply. Therefore, it is certain to say that \_\_\_\_\_\_\_\_\_\_\_.
bigger wire is required on a 120 volts that on a 240 volts current supply.
Here's a proof:
1200/120 volt supply = 10 amperes
1200/240 volts supply = 5 amperes
71
A smaller diameter wire on a 240 volts current can safely carry more current in proportion with its weight than a larger diameter wire on a 120 volts supply current.
72
The ___ the circuit voltage the more economical the system will be.
Higher
73
1 HP =
746 watts
74
The owner of a 5kw electric motor irrigation pump, requested line connection from the electric cooperative. The owner was given an option to avail of either 120 or 240 volts service. What is the good choice if the circuit line has a resistance of .42 Ohms?
75
Voltage Drop formula :
Voltage Drop = V/Supply Volt = % of Voltage Drop
76
AWG
American Wire Gauge
77
Wire size and ampere capacity
Identify ampere capacity
no 14 (2mm2)
15 ampere
78
Wire size and ampere capacity
Identify ampere capacity
no 12 (3.5mm2)
20 ampere
79
Wire size and ampere capacity
Identify ampere capacity
no 10 (5.5mm2)
30 ampere
80
Wire size and ampere capacity
Identify ampere capacity
No. 8 (8mm2)
40 ampere
81
Wire size and ampere capacity
Identify ampere capacity
No 6
55 ampere
82
Wire size and ampere capacity
Identify ampere capacity
no 4
70 ampere
83
Wire size and ampere capacity
Identify ampere capacity
no. 0
125 ampere
84
\_\_\_ insulators are those with extremely high resistance to current flow and moderate resistance to load resistor.
Good
85
Insulation is rated by voltage from 300 to 15000 volts. If the insulation used is above its specified rating, the ____ is high which might cause short circuit and arcing that may result to fire.
Risk of breakdown
86
Ordinary conductor wieres for buildings is normally rated at ___ or ___ volts
300 or 600 volts
87
\_\_ are those electrical conductors 8..2 (AWG no 8) and smaller in sizes.
Wires
88
\_\_\_ on the other hand are those which are larger than the wires.
Cables
89
2 types of cables or wires.
Stranded Wire or Solid WIre
90
Consists of a group of wires twisted to form a metallic string. THe circular mil area of a stranded wire is found by multiplying the circular mil area of each strand by the total number of strand.
Stranded Wire
91
\_\_ is the term given to an insulated stranded wire.
Cord
92
The word __ that is equal to 1/1000 of an inch was used to describe or measure a rounded wire diameter. If a wiere has a diameter of one mil, it has a cross sectional area of one circular mil.
Mil
93
1 diameter mil
1 circular mil
94
mil=
1/1000"
95
Different types of Electric wire and cables.
60d C
1.60mm - 500mm2 solid and stranded
Ordinary building wire
TW oil resistant thermoplastic
96
Different types of Electric wire and cables.
75d C
1.6mm - 500mm2 solid and stranded
Building wire wet and dry location
THW oil, heat and moisture resistant thermoplastic
97
Different types of Electric wire and cables.
60dC
.6mm - .3mm2 solid and stranded
Fiture wire single conductor 2 conductor twister or parallel 3 conductor twisted
TF thermoplastic fixture wire
98
Different types of Electric wire and cables.
Copper
1.6mm - 500mm2
Bare overhead transmission line and for ground wire.
Bare copper wire (solid) and stranded.
99
Different types of Electric wire and cables.
1.50 mm - .39mm2 solid and stranded 2-3 and 4 conductors
General purpose
60 d C
Armored (BX) Cable
100
Different types of Electric wire and cables.
no 24 - no20
300 ohms tv wire
TV antenna wire
101
Different types of Electric wire and cables.
no 18 - no 2
105dC
Primary wire spark plug and battery cable
Automotive wire
102
60dC
no 14 - no 10
no 8 - no 1000 MCM
Power cable for aerial and duct 600 volts power cable for aerial duct and direct burial 600 voltz
Power cable
103
Different types of Electric wire and cables.
1.60 mm - 2.60mm2
2,3 and 4 conductors round or flat
For exposed or concealed works in air voilds in masonry blocks or tilewalls not exposed to excessive moisture or dampness. 600 volts
Non metallic sheathed cable type NM
104
Different types of Electric wire and cables.
22/3 conductors
Extension cord telephone equipment
Jacketed wire
105
Different types of Electric wire and cables.
1 pair thru 100 pairs
Interior communications and sound system
Intercom cable shileded or unshielded
106
Different types of Electric wire and cables.
60dC
No 6 - no 4/0
Arc welding machine
Welding cable
107
60dC
No 14 - no 1
2 and 3 conductors round connection.
For submersible pumps of deep wells
Submersible pump cable
108
Characteristics of Selected Insulated conductors for General Wiring:
KHW
75dC
FOr Dry and Wet location
Moisture and HEat resistant Rubber
109
Characteristics of Selected Insulated conductors for General Wiring:
T/TW
60dC
Dry Location
Dy and wet location
Thermoplastic moisture resistant thermoplastic
110
Characteristics of Selected Insulated conductors for General Wiring:
THHN
THW
90dC
75dC
Dry location, Dy and wet location
Thermoplastic heat resistant
Moisture and heat resistant thermoplastic
111
Characteristics of Selected Insulated conductors for General Wiring:
THWN
75dC
Dry and wet location
Moisture and heat resistant thermoplastic
112
Characteristics of Selected Insulated conductors for General Wiring:
XHHW
90dC
Dry location
Moisture and heat resistant cross linked thermosetting
113
Characteristics of Selected Insulated conductors for General Wiring:
SA
90C
Dry location
Silicon Asbestos
114
Characteristics of Selected Insulated conductors for General Wiring:
AVA
110dC
Dry location
Asbestos and varnish cambric
115
find how many circular mils are there in 21 stranded conductor:
116
Circular mil to Square millimiter
Circular mil x 0.0005067
117
MCM stands for
thousand circular mils
118
What is the equivalent size in square millimeter of a cable 250 MCM?
250 MCM = 250,000 circular mils
250,000 x .0005067
= 126.67 mm2
119
what is Bare Conductors for?
For Grounding
120
Type of Cables
is a fabricated assembly of insulated conductors enclosed in flexbile metal sheath. Armored cable is used both on exposed and concealed work.
Armored Cable (AC)
121
122
Type of Cables
is a factory assembled cable of one or more conductors each individually insulated and enclosed in a metallic sheath of interlocking tape of a smooth or corrugated tube This type of cable is especially used for service feeders, branch circuit and for indoor or outdoor work.
Metal Clad Cable
123
Metal Clad Cable (MC)
124
Type of Cables
is a factory asembly of one or more conductors insulated wit ha highly compressed refractory mineral insulation enclosed in a liquid and gas tight continuous copper sheath. This type of cable is used in dry, wet or continuously moist location as service feeders or branch circuit.
Miniral insulated cable MI
125
Mineral insulated Cable (MI)
126
Type of Cables
Is also a factory assembly of two or more insulated conductors having a moisture resistant, flame retardant, and non-metallic material outer sheath. This type is used specifically for one or two family dwellings not exceeding 3 storey buildings.
Non metallic Sheated cable (NM)
127
Non-MEtallic Sheathed cable (NM)
128
Type of Cables
This type of cable is a factory assembly of two or more insulated conductors in an extruded core of moisture resistant and flame retardant material covered within an overlapping spiral metal tape. This type is used in hazardous locations and in cable trays or in raceways.
Shielded Non-Metallic Sheathed Cable (SNM)
129
Shielded Non-Metallic Sheathed Cable (SNM)
130
Types of Cables
Is a moisture resistant cable used for underground conections including direct burial in the ground as feeder or branch circuit.
Underground Feeder and Branch Circuit Cable (UF)
131
Underground Feeder and Branch Circuit Cable (UF)
132
Type of Cables
is of the types SE and USE. A single or multi conductor asembly provided or without an overall covering primarily used for service wire.
Service Entrance Cable
133
Service Entrance Cable
134
Types of Cables
This is a factory assembled two or more insulated conductors with or without associated bare or covered grounding under a metallic sheath. This is sued for installation in cable trays, raceways or where it is supported by messenger wire.
Power and Control Tray Cable (TC)
135
Power and Control Tray Cable
136
Types of Cables
is an assembly of parallel conductors formed integrally with an insulating material web designed specially for field installation in metal surface or raceways.
Flat Cable Assemblies (FC)
137
Types of Cables
consists of three or more flat copper conductor placed edge to edge separated and enclosed within an insulating assembly. This type of cable is used for general purposes such as: appliance branch circuits, and for individual branch circuits, esp in hard smooth continuous floor surfaces and the like.
Flat conductor cable (FCC)
138
Types of cables
is a single or multi conductor solid dielectric insulated cable rated at 2000 volts or higher This type isused for power system up to 35,000 volts.
Medium Voltage cable (MV cable)
139
is defined as the ability of the wire or conductor to carry current without overheating. Conductor resistance to current flow, generaly not ony heat but also contribute to the voltage drop,
Ampacity
140
\_\_\_ is equal to the components resistance times the current squared.
Power Loss
141
Conductor size and rating shall have sufficient ampacity to carry load, They shall have adequate mechanical strength and shall not be less than the rating of the branch circuit and not less the \_\_\_.
Maimum load to be served
142
\_\_\_ is determine by the maximum operating temperature that its insulation can withsatand continuously without heating. Current flow and conductor's resistance normally generates heat.
Conductors Ampacity
143
\_\_ refers to either enclosed or open condition on which the wire is placed.
Environtment
144
\_\_\_\_ or ability of the conductor to carry load, increases as the sizes of conductor increases. If more than 3 conductors are inserted into a conduit, the temperature also increases and it requires derating of the conductors ampacity.
Ampacity
145
60dC up to ___ AWG copper wire
no 8
146
75d C for bigger than ___ AWG copper wire
75dC
147
means that, the full amount of allowable ampacity, is reduced to a certain percentage due to the environmental condition it is exposed of and the number of wires placed inside the conduit.
Derating of Conductors Ampacity
148
\_\_\_ are channels or wiring accessories so designed for holdign wires, cables or busbards that are either made of metal, plastic or any insulating mediums.
Raceways
149
Common types of raceways for household wiring
The Conduits
The connectors and other accessories
150
\_\_ is the most common electrical raceways used in all types of construction.
Conduit Pipe
151
Types of conduit materials:
Metallic suchas steel pipes or aluminum
Non-metallic such as plastic and the like
152
\_\_ is a metal sleeve usually made of copper that is slipped over and secured to the butted ends of conductors in making a joint.
Connector
153
Connector is otherwise called \_\_\_.
Splicing sleeve
154
EMT
Electrical metallic tubing (EMT)
Intermediate metal conduit (IMC) is a steel tubing heavier than EMT but lighter than RMC. It may be threaded. Electrical metallic tubing (EMT), sometimes called thin-wall, is commonly used instead of galvanized rigid conduit (GRC), as it is less costly and lighter than GRC.
155
Stamped steel
156
Malleable Iron
157
C CLamp
158
Pipe clamps
159
U Bolt
160
Side beam clamp
161
\_\_\_\_ connectors are used to secure EMT conduits to electrical metallic box.
EMT
Konkore EMT fittings are similar to conventional EMT fittingsboth using either set-screw or compression rings to secure EMTpipes. Connectors are mounted to a metallic box using a steel locknut that screw on standard NPSM threads. ...
162
Compression Type Rain Tight Connection
163
Compression Type Rain Tight Coupling
164
Set Screw Connector Insulated
165
Set Screw Coupling
166
An ___ is a point in the wiring system at which current is taken to supply utulization equipment. In a simple term, an outlet is any point that supplies an electric load.
Outlet
167
An ____ usually consists of a small metal or non-metal box into which a raceway and or cable ends.
Outlet
168
A ___ is a device that by insertion into a receptacle establishes connection between the conductor of the flexible cord and the conductors connected permanently to the receptacle.
Convenience outlet or attachment cap
169
2 Pole 3 wire
170
3 pole 4 wire locking
171
Clock Outlet
172
The common wall outlet is called \_\_\_\_.
COnvenience outlet
173
A ___ is another name for the attachment cap on the wire coming from a device such as lamps or appliances.
PLug
174
octagonal outlet box
used for ceiling and walls
175
round outlet box
used in ceiling
176
rectangular outlet box
used in ceiling and walls
177
Flush Floor Box
178
Utility BOx
179
Adjustable Junction Box
180
Is an outlet intended for direct connection to a lamp holder, lighting fixture, or a pendant cord, terminating in a lamp holder.
Lighting Outlet
181
Is an outlet where one or more receptacles are installed.
Receptacle outlet
182
Is not an outlet. By definition, it does not supply current to utilization device.
Junction box
Do not allow your electrical contractor to count wall switches and junctions boces as outlets.
183
An __ on the other hand, refers only to the box intself. It does not include the items. The receptacle device is not an electrical load but rather anextension of the box wiring. It is separate from the load device even if it is included as part of the device.
Outlet
184
\_\_\_ is a box with a blank cover that is inserted in one or more runs or raceways to facilitate pulling-in the conductors. It may also serve to distribute the conductors.
Pull Box
185
\_\_\_\_ are contact device installed at the outlet for the connection of a single attachment plug. Receptacles are included in the general classification of wiring devices. It includes all receptacles and their matching cap (plug), wall switches, small dimmers and outlet box mounted lights.
Receptacles
186
A contact device installed at the outlet for the connection of a single attachment plug.
Receptacle
187
A ___ is a device that open or closed the circuitry in an electric circuit.
Switch
188
Rotary Switch
189
Toggle Switch
190
Key Switch
191
momentary contact switch
192
Maintained Contact Switch
193
The ____ switch is intended for use in thegeneral distribution and branch circuit rated in amperes. It is capable of interrupting the rated current at a rated voltage.
General Use Switch
194
The ___ siwtch is a form of general use siwtch isntalled in flush device boxes or an outlet box cover..
General use snap switch
195
The __ siwtch is a switch intended for isolating an electric circuit from the source of power.
Isolating Switch
196
\_\_ refers to the complete path travesed by an electric current. Electric circuit is the entire house wiring installation.
Electric Circuit
197
\_\_\_\_ is defined by the national electrical code (NEC) as "The circuit conductors between the final over current protective device and the outlets." Wiring installed between the circuit over current protective deviec, eg. fuse, or circuit brear and the outlets.
Branch Circuit
198
means that the installation can accomodate all probable pattern arrangements and location of the loads for expansion or future development
Flexibility of the Circuit
199
\_\_\_ means that independent service can be used in line of emergency equipment as backup for normal services.
Safety
200
\_\_\_\_ circuit supplies outlets for lighting and appliances, including convenience receptacles.
General Purpose Branch Circuit
201
\_\_\_\_ circuit supplies outlets intended for feeding appliances. Fixed lighting however, is not supplied.
Appliane Branch Circuit
202
\_\_\_ circuit is designed to supply a single specific item.
Individual branch circuit
203
The code requires sufficient circuitry to supply residential load of ___ watts per square meter in buildings excluding porches, garages and basements.
30
204
Thre requirement of 30 waatts per square meter is up to ___ sq.m for a 20 amperes circuit (2400 watts) or 60 square meters for 15 amperes circuit (1800 watts).
80
205
Good practice suggests that the load should not exceed ___ watts for a 20 amperes circuit and __ watts for a 15 amperes circuit.
1600
1200
206
15amperes circuit with a maximum area of \_\_\_\_
40 sqm
207
20 amperes circuit with a maximum area of __ sqm
53 sqm
208
minimum amperes for branch circuit to feed all small appliance outlets in the kitchen, pantry, dining and family room.
20 amp
209
wire size for 20 amp.
no. 12
210
Code says. All receptacles are potential appliance outlet and at least __ circuits shall be supplied to serve them.
2
211
Code says. At least one ___ amp circuit supply the laundry outlets
20
212
Lighting and receptacles should not be combined in a \_\_\_.
Single Circuit
213
Lighting and receptaacles should be supplied with current from at least __ circuits so that if a single line is out, the entire area is not deprived of power.
two
214
Provide at least one receptacle in the ___ and \_\_\_. Both must be Ground Fault Circuit Interrupter (GFCI) type.
Bathroom
Outside the house
215
Convenience outlet though counted as part of the general lighting load shall be limited to __ CO on 15amp.
6
216
Convenience outlet though counted as part of the general lighting load shall be limited to __ CO on 20amp.
8
217
at least ___ amp circuit supply shall be installed to the laundry outlets.
20
218
Convenience outlet shall be laid out in such a manner that no point on a wall is more than \_\_\_m from an outlet. use a groundign type receptacle only.
2.00m
219
As a rule, branch circuit should be protected from over current. Hence, an over all ____ shall be installed in all branch circuitries.
current protective devices
220
The protective devices has but one purpose - to \_\_\_, in case there is an excess current flow in the circuit.
to interrupt the line
221
The action of the over current protective device is called \_\_\_\_. because it clears the circuit of the ault or over current load. It therefore acts in the same manner as the mechanical device to relieve the machine from excessive pressure.
clearing
222
Pressure relief valve in analogy to electrical
Circuit Breaker
223
Application of OVer current protection
That the over current protection devices should be installed on the line or ____ of the equipment being proteected.
Supply side
224
\_\_\_ is defined as, an over all current protective device with a circuit opening fusible element which opens (break) when there is an over current in the circuit.
Fuse
225
The ____ is a one time protective device to be replaced after the fault is cleared.
Fuse
226
Fuse consist of a fusible link or wire that easily melt at low temperature:
The ____ which is enclosed in an insulating fiber tube.
Cartridge Type
227
Fuse consist of a fusible link or wire that easily melt at low temperature:
The ___ enclosed in a porcelain cap.
Plug fuse type
228
The ___ is an over current protective device designed to function as a switch.
Circuit Breaker
229
\_\_\_ refers to the cutting off or disconnection of the current supply.
Trip or Tripping
230
The ___ is defined by the National Electrical Code as "a single panel or group panel limits designed for assembly in the form of a single panel."
Panel Board
231
\_\_\_ is simpy the box wherein the protective devices are grouped from which they are fed.
Panel Board
232
If the devices are fuses, it is called \_\_\_\_.
Fuse Panel
233
Ifi the devices are circuit breakers, it is called \_\_\_.
Breaker Panel
234
A single phase, 3-wire panel is fed with ____ and a ___ connected to the line buses and the neutral bus which varies in:
Ampere ratings of the buses
Type of protective devices installed.
Two hot lines
Neutral line
235
Wires for Single Pole:
1 Hot
1 Neutral
Ground
236
Wires for Two Pole:
2 Hot
1 Neutral
Ground
237
There are as many different format of panel schedule as the numbers of technologists and every one believes that his work is the best. hence, it will be called \_\_\_\_\>
Schedule of Choice
238
Principles applied in Installing Panel Board:
It must be installed near the load center, as in most cases panel boards are mounted near the \_\_\_\_
kitchen and the laundry where heavy duty loads are expected
239
Principles applied in Installing Panel Board:
To limit voltage drop on the branch circuit, the panel board shall be located in such a manner that no circuit wiring connections exceed ___ meters long.
3.5m
240
Principles applied in Installing Panel Board:
In the vent that a circuit more than 3.5 meters long cannot be avoided. ____ wire shall be used for runs up to 50 meters long and ___ wire for longer circuits.
no 10 AWG
no 8 AWG
241
A panel board with 100cm high or less should be located ___ from the floor to the center line of the box.
135cm
242
Panel board with boxes over 100cm high should be located __ cm from the floor to the bottom of the box, except that the highest branch circuit unit should not be more than ____ cm from the floor.
75
195
243
If necessary, the box maybe lowered to a distance not less than ___ from the floor to the bottom of the box. However, where a maximum height of 195 cm above the floor to the upper circuit or a minimum distance of 45cm above the floor cannot be done the panel should be divided into \_\_\_\_.
45cm
two sections
244
If two or more boxes are adjacent on the same wall, they should be installed with the horizontal center line of each box equidistance from the floor. The center line distance of the higher box controlling the boxes should be installed with a minimum spacing of ___ apart.
10 cm
245
Other features of the over current protective device.
The upstream side of the device is called \_\_\_\_. The downstrean side is called the \_\_\_.
Line side
Load side
246
The ____ and ____ are free standing assemblies of switches, fuses and circuit breakers that provide switching and feeder protection to a number of circuits connected to the main source. It distribute large amount of power into small packages.
Switchboard and Switchgear
247
The National Electrical Code requires an entirely separate emergency standby electric supply system on ___ and ____ establishments. The concept of the emergency standby system is to replace normal power supply to selected or entire loads within the building in case of utility power outage.
Commercial
Industrial
248
Where emergency loads are large enough that batteries could not be economically feasible, and where 8 to 15 seconds starting time is telerable, a ____ is employed.
Generator set
249
The ___ is defined as that portion of the supply conductors which extends from the street main duct or transformer to the service or switchboard of the building supply.
Service Entrance
250
The conductor and equipment for the delivering energy from the electricity supply system to the wiring system of the premises served.
SErvice Entrance
251
The ___ is the common type of service wire installed by electric power supply companies for industrial, commercial and residential houses. A service drop, is connected from the nearest utility pole to the building service entrance pointand enter the building through the weather head, down to the electric power meter.
Overhead Service Entrance
252
The ____ consists of a raceway (conduit) extending from the building to the property line where it is tapped to the main.
Type of Service Entrance
Underground Service
253
The cable recommended for underground service entrance is the ___ type cable. A low voltage cable is not advisable for installation in a concrete enveloped raceway, except, when the service equipment is not at the point at which the ground run meets the building.
USE (Underground Service Entrance)
254
Three Porcelain Spool Insulators on a Secondary Rack
255
Minimum size of conduit for service conductor:
25mm diameter
256
Minimum wire size for service wire:
No 8 (8mm2)
257
Service entrance may be 2 wires of 120/240 volt or 4 wire with 120/208 or 277/480 volts for larger installations. In each case, the size of the service wire varies from 60, 100, or 200 amperes depending upon the demand load, but generally, the ___ wire service entrance does not exceed __ amperes.
60
258
\_\_\_\_ is generally installed outside the building at the propoerty lien wall, or electric post for ready access to the meter reader, making it more difficult to tamper or to install jumpers. For multi door services such as apartments and commercial establishments, the use of a master metering is preferred. A battery of metrs are installed in a central meter room or reserved space to facilitate the meter reading and making it a one stop affair.
Electric Meter
259
All circuit conductors between the service equipment or the generator switchboard of an isolated plant, and the final branch circuit over current device.
The Feeder
260
Feeder for ____ shall be independent and totally separated from the light circuits.
electrical motor
261
Feeders requiring more than ____ diameter conduit pipe should not be used.
50mm diameter
262
The ____ is a feeder interior wiring extending from the service switch, generator buss, or converter bus, to the main distribution center or electric service equipments.
Main
263
The service equipment should be centrally located to shorten all home runs. Branch circuit run in excess of ____ will have an excessive voltage drop.
30 meters
264
Location of the Service Equipment
In residential houses, it is located near the heaviest load center such as \_\_\_\_.
kitchen and the laundry area
265
The ____ electricty, is a Triple Circuit. The lighting and outlet loads are connected between any phase leg and a neutral line. Machineries and other bigger loads are connected to the phase leg only.
Three Phase
266
The three phase system, is used in buildings where the loads exceed 50kVa, or where it is required for the bigger loa such as motors and machineries.
267
The neutral conductor of a three phase system, although common to all three lines, only carries the \_\_\_\_. Thus the neutral conductor carries no current when loads both sides of it are balanced. Meaning, if the two legs carries the same load of say 120 volts, the neutral line is zero voltage.
Unbalanced Current
268
Difference between single phase and three phase
The single-phase power supply has one distinct wave cycle whereas; three phase has three distinct wave cycles. Single phaserequires the single wire to connect the circuit whereas; 3-phaseneeds 3-wires. The voltage of the single phase is 230V, whereasthree phase voltage is 415V.
269
A ___ alternating current can either be 2 or 3 wires. However, a 3 pahse AC has 3 or 4 wires consisting of 3 hout loegs designated as A,B, and C plus a neutral wire designated with letter N. The common electrical circuit serving residential buildign is the two wires receptacle circuit thatfeeds the ceiling and the wall plug. The service entrance is sometimes 3 wires circuit written as, 3 wire 120/240 volt 60 hertz
Single Phase
270
Advantages of the Three Phase System
The 120 volt is for the lighting and receptacles outlet only.
the 240 volt is for bigger loads.
votlage drop is lower
smaller wire is used
271
3 phase conductor wires color coded
Neutral
White or gray color
272
3 phase conductor wires color coded
First Hot line A
Black Color
273
3 phase conductor wires color coded
Second Hot line B
Red Color
274
A diagram wherein the major components are represented by rectangles or blocks.
Block Diagram
275
Diagram presented showing the spatial relations between components.
Riser Diagram
276
Diagram which electrical symbols are used instead of blocks.
One Line or a Single Line Diagram
277
The ____ is the power supplied by company like Meralco and Electric Cooperative or what the transformer produces.
System Voltage
278
\_\_\_ on the other hand, is the current being utilized after some normal voltage drop.
Utilization Voltage
279
When specifying transformer, used the ____ voltage (240/480). For electric motors use ___ voltage (240/460). The 4% utilization voltage drop is within the normal motor tolerance.
System Voltage
Utilization Voltage
280
The national electrical code (NEC) defines ____ as Zero Voltage.
Ground
281
The purposed of grounding the circuit is to \_\_\_\_\_
fix permanently a zero voltage point in the system. The grouned line of a circuit should not be broken nor fused to maintain a solid and uninterrupted connection to the ground. An stablished ground automatically becomesthe reference for all voltage in the system.
282
Grounding could be accomplished by: (3)
Connecting to a buried cold water main
to Groud rod
to buried ground plate
283
All new installations shall use grounded outlets such as ___ and ____ devices on all appliance circuits more particularly on outdoors and bathroom locations of outlets.
GFI and GFCI
284
\_\_\_\_ is the technical term for the House Wiring Installation. House wiring varies in sizes depending upon the kind of load it is to serve.
Branch circuit
285
\_\_\_ refers to the electricity drawn or consumed by lighting fixtures, appliances, equipment etc.
Load
286
The Code provides that wirings for electric circuitry shall be of the types _____ (6) in a raceway or cables.
RHW
T
THW
TW
THWN
XHHW
287
Om a 15 amperes circuit, a single appliance shall not draw a maximum load of more than ___ amp.
12
288
on a 20 amperes circuit, a single appliance shall not draw current in excess of __ amp.
16
289
If a branch circuit is combined with lighting or portable appliances, any fixed appliance shall not be allowed to draw more than ___ amp on a 15 amp circuit and __ amp on a 20 amp circuit.
7.5
10
290
That on a 30 amperes circuit, a single appliance draw shall not exceed __ amp.
24
291
A heavy lamp holders shall be rated not less than ___ watts
750
292
A ___ amperes circuit shall not be used for fixed lighting in residences.
30, 40, 50
293
When loads are conneceted for a long period of time, its actual load shall be computed not to exceed ___ of the fuse rating. Long period of time refers to electric motors, air conditioner and other similar units with a continuous loading.
80%
294
A continuous type load shall be considered at 125% of the actual load in all load calculations.
125%
295
Receptacles feeding portable and or steady appliance shall be limited to loads of 80% of their rating.
12 amp for ___ amp receptacle
16 amp for ___ amp receptacle
24 amp for ___ amp receptacle
15
20
30
296
The number of outlets in a circuit shall be limited to:
\_\_ outlets on a 15 ampere circuit
\_\_ outlets on a 20 ampere circuit
6
8
297
Unit Watts per Sq. M
that has
24 watts/sq m
Dwelling UNits
Schools
Stores
Beauty parlor and barber shops
298
\_\_\_ watts shall be the maximum load for each house hold lighting outlet.
100 watts
299
Ampacity of the connected load shall not exceed ___ of the amperage capacity of the conductor and the fuse.
80%
300
For each single receptacle shal be considered at no less than ___ watts rating.
180 watts
301
The code specifically mandated the use of a ___ copper wire as the minimum size for all types of convenience outlet wiring except for an appliance with limited load wherein a 2.00mm2 or no 14 AWG wire is permitted.
3.5mm2 or No 12 AWG
302
the Code limits the use of ___ conductor as minimum size for service entrance.
8.00mm2 or no 8 AWG
303
Service entrance shall have sufficient ampacity to carry the building load. They shall have adequate mechanical strength and shall not be small than __ diameter except for installation to supply limited load of a single branch circuit such as small poly-phase power, controlled water heaters and the like and they shall not be smaller than ___ or ___ diamter copper or equivalent.
8mm2 or 3.2mm diameter
3.5mm2
2mm2
304
Artcle 6.7 of the Philippine Electrical Code (PEC) provides that: "Branch circuit conductor supplying a motor shall have an ampacity not less than ___ of the full load current. eg. ACU
125%
305
The code on branch circuit protection for a single motor provides that. It shall be increased by ___ of the full load current of the motor.
250%
306
The Neutral conductor of a 3-wire line to line supply system shall have an ampacity of not less than ___ of the ungrounded (live wire) conductor or Two Trade Size smaller than the ungrounded conductor.
70%
307
If the computed load exceeds 10000 watts, the conductor and overcurrent protection shall be rated not less than ___ amperes.
100
308
The Branch circuit and receptacles for small appliance load shall be rated at no less than ____ watts. However, if the number of receptacles were indicated and specified in the plan, the load is computed ___ watts per outlet.
1500
180
309
The protection rating or setting of a motor shall be __ percent (maximum) of the ful load current of the biggest motor being served plus the sum of the full load current of the other motors.
250%
310
Symbol for:
Antenna
Lightning Arrester(indicate Kv rating)
Circuit Breaker, indicate rating and setting
Fuse cutout, indicate rating
Ground
Transformer, Indicate Kva type, voltge and phase
Service Entrance. indicate number of conductors, size type and voltage
311
\_\_\_\_\_ lamp are critically dependent on the wattage supply that even for a small fluctuation of the current voltage, its life, output, and efficiency is materially affected.
Incandescent Lamps
312
The _____ bulb or lamp is a source of electric light that works by incandescence, which is the emission of light caused by heating the filament. They are made in an extremely wide range of sizes, wattages, and voltages.
last on average for 1 year.
do not contain mercury.
They can be used with a dimmer switch.
incandescent light
In 2007 Congress passed the Energy Independence and Security Act requiring new energy-efficient standards for basic light bulbs. All standard 100-, 75-, 60- and 40-watt incandescent bulbs are being phased out and will no longer be produced.
313
\_\_\_\_\_\_ bulbs are currently the most energy efficient of all types of light bulbs. The materials used to generate the light are encased within a solid material (“solid-state” technology). Practically, this translates into a lamp with a rated life much longer than those using non-solid-state technology.
Available for outdoor use; just make sure the packaging indicates the bulb is rated for outdoor use.
Does not contribute to heat buildup, which helps save on air conditioning.
Suited for signs and indicators, night lights, flashlights, undercabinet fixtures, and some recessed light/downlight applications where the constancy of color temperature is not critical.
Light emitting diode (LED)
314
\_\_\_\_\_ bulbs are primarily used in larger spaces such as warehouses, commercial buildings or in streetlights. They are filled with sodium or mercury vapor that conducts electricity. These bulbs don't have filaments like most light bulbs, so they last longer.
These lamps are used primarily in applications where the most critical factor is creating as much visible light per watt as possible. **Major applications include streetlights, gymnasiums, warehouses, large retail facilities, and stadiums, and plant growing rooms.**
High Intensity Discharge (HID)
315
\_\_\_\_\_ bulbs—easily identified by their hallmark curlicue design—use a fraction of the wattage incandescent bulbs use. Both come in a wide variety of wattages, sizes, color temperatures, and base types, and they are known primarily for their efficiency, long life, low cost, and ease of upgrading.
Good for reading and project work.
Don’t work with dimmer switches and aren’t particularly well suited for light fixtures you switch on.
Compact fluorescent (CFL)
316
The ______ light bulb or lamp is a type of gas-discharge lamp. Linear fluorescent bulbs come in a wide variety of lengths, diameters, wattages, and color temperatures.
Known for high energy efficiency, long life, and relatively low cost.
Fluorescent tubes will not work without a ballast.
linear fluorescent
317
The ____ light bulb or lamp is a type of incandescent lamp which uses a halogen gas in order to increase both light output and rated life, but they use less energy.
Last two to three times longer than standard incandescent bulbs.
Smaller in size than standard light bulbs.
Capable of producing brighter light than standard incandescent designs.
After about 750 to 1000 hours of use, the filament eventually gets so thin that it breaks, which is what happens when your light bulb “burns out.” But, with the invention of the halogen bulb, there is a new solution to illuminate your space without some of the complications of incandescent bulbs.
halogen
318
\_\_\_ Light is a sort of LED light made with environmentally-friendly silicone injections. Each bulb is made from the highest quality resin, found only in Burma. It is very transparent, it won't break when it's dropped, and it is not hot to the touch even after it has been illuminated for hours.
The actual color and paint curves inside is totally random and unique, which makes each piece an artwork.
E.P. Light
319
\_\_\_ was first introduced in 1937. It was considered the best, and most widely used type of Lamp. Generally it comes in varieties of sizes, wattages, colors, voltages and specific application.
Fluorescent Lamp
320
The ___ fluorescent lamp is the most common type comprising of a cylindrical glass tube sealed at both ends, containing a mixture of an inert gas generally arggon, and low pressure mercury vapor.
Cathode
321
The fluorescenet lamp is so called because its ___ radiate light when exposed to ultra violet rays.
Phosphors
322
Fluorescent lamp requires ___ in its circuit.
ballast
323
The ____ is basically made of coil to limit the current in the circuit in which, if not controlled, will open the fuse or circuit breaker.
ballast
324
\_\_\_ refers to the amount of energy converted to visible light.
Efficiency
325
Is a measure of the lumens per watt produced by the lamp
Efficacy
326
Fluorescent lamp has longer life span compared with the incandescent lamp. Its life span is materially affected by \_\_\_\_.
number of times the lamp is switched on and switched off
327
The original fluorescent lamp is the \_\_\_\_\_. The circuit used is a separate starter. When the lamp circuit is closed, the starter energizes the cathod. After 2 to 5 seconds delay, it initiates a high voltage arc across the lamp causing it to start.
Preheated design
328
F20 T12 WW means
Fluorescent lamp 20 watts, Tubular shaped bulb 12/8 inches diamter, Warm white
329
\_\_\_\_ was introduced in 1952. It was typically the same in construction as the preheat lamp. The basic difference is the circuitry that eliminates the delay inherent in preheat circuit by constantly keeping the cathodes energized or preheated.
Rapid Start Lamp
330
Rapid Start Lamp Type:
operates at 800amp
High Output
331
Rapid Start Lamp Type:
operates at 1500milliamperes.
Very high output
332
F48 T 12/CW/VHO means
Fluorescent 48 in long
Tubular 12/8 in diamter bulb
Cool White
Very High Output (1500mla)
333
This type of fluorescent lamp was introduced in 1944. It was called the ___ considered the best among the varieties of instant start fluorescent lamps.
Slim Lamp
334
\_\_\_\_ is another type of lamp that offers a very long life service compared with the hot cathode lamp. The lamp is not affected by the number of starting or switching of the lamp. It has a lower overall efficacy compared to the hot cathode lamp and is generally used where a long continuous burning is required.
Cold Cathod Tube
335
\_\_\_\_\_ is a combination of the arc discharge characteristics of a fluorecent lamp and the compact focusable shape of an incandescent lamp. The combination effect is responsible for its efficiency and long life in various uses.
Mercury lamp
336
The lamp life of a mercury lamp is extremely long with an average of ____ based on 10 burning hours per start.
24,000 hours.
337
Types of Ballast
is a low power factor and does not require voltage regulation. This is only used where line voltage fluctuation does not exceed plus or minus 5%
Reactor Ballast
338
Types of Ballast
Is a reactor unit with transformer to match line voltage to lamp voltage. It has a low power factor and non regulating.
Auto Transformer Ballast
339
Dimming of mercury lamp is possible by using a ____ and a ____ control available for 400-700 and 1000 watts.
dimming ballast,
solid state dimming control
340
Types of Ballast
is the same as type 2 except the additional capacitor to improve the power factor.
High Power Factor Auto Transformer Ballast
341
Types of Ballast
is also called lead circuit ballast. A regulating high power factor unit that maintains lamp voltage making wattage and lumen output constant. The lamp wattage varies from 5% with a 10% voltage change.
Constant Wattage Auto Transformer Ballast
342
\_\_\_\_\_ is mercury lamp, improved by the addition of halides of metal such as Thallium, Indium, or Sodium to the arc tube.
Metal Halide Lamp
343
\_\_\_\_\_ was first developed and introduced by General Electric Co (GE). THis is one of the latest developements in the high intensity discharge (HID) lamps. It is marked under the trade name Lucalux, Ceramalux, and Analox.
High Pressure Sodium Lamp
344
\_\_\_ are used in open bottom fixtures or where glare is a problem. Special ballast is required.
Lumalux Coated Lamps
345
type of lamp also called SOX. It produces light of sodium characteristics monochromatic deep yellow color. Not applicable for general lighting because of its very high efficacy over 150 lumens per watt including ballast loss.
Low Pressure Sodium Lamp
346
\_\_\_\_ is a chemical element with symbol Na (from Latin natrium) and atomic number 11. It is a soft, silvery-white, highly reactive metal.
Sodium
347
The ____ lamp is popularly called Quartz Lamp. It is a special type of incandescent lamp. One advantage it has over the nomarl incandescent lamp is its ability to maintain a constatnt level of light output throughout its life.
Tungsten-halogen lamp
348
\_\_\_\_ are electrical devices designed to hold and connecet the lamps to power supply as well as control and distribute the light, and to position and protect the lamp.
Lighting Fixtures
eg: lamp holders, reflectros, or shields, diffusers
349
\_\_\_ is defined as the intensity of light per unit area.
Illumination
350
\_\_\_\_ is the production of light by means of electricity and its applications to provide efficient, comfort, and safe vision.
Electric illumination
351
refers to the amount of illumination or luminous flux per unit area.
Quantity of Light
352
\_\_\_ refers to the distribution of brightness in the lighting installation.
Quality of Light
353
Is the light that seems to radiate from an object being viewed. It is the luminous flux (light) emitted, transmitted or reflected from a surface.
Brightness
354
\_\_\_\_ is the difference in brightness or the brightness ratio between an object and its background. The recommended brightness ratio between an object being viewed and its background is nomally 3:1
Contrastt
355
Is a strong, steady, dazzling light or reflection. The quality of the lighting system must also include the visual comfort of the lighting system must also include the visual comfort of the system, that is, the absence of glare.
Glare
356
Types of Glare:
is an annoying brightness of light in persons normal field of vision
Direct Glare
357
Types of Glare:
\_\_\_\_ is much more serious anddifficult to control. Technically, reflected glare is a glossy object.
Indirect or Reflected Glare
358
\_\_\_\_ refers to the control of shadows cast by light. It is the degree to which light is shadowless, and is therefore a function of the number of directions to which light collides with a particular point and the comparative intensities.
Diffuseness
359
\_\_\_\_ is an equal intensity of light clashing from directions producing no shadows.
Perfect Diffusion
360
A ____ provides a satisfactory diffused illumination and less shadows.
PErfect Diffusion
361
is the quality attribute by which we reconize and describe colors as red, blue, yellow, green, violet and so on
Hue
362
is the difference between the resultant colors of the same hue, such as: white is the most brilliant of the neutral colors while black is the least.
Brilliance
363
\_\_\_ is the difference from the purity of the colors. Colors of high saturation must be used in a well lit spaces.
Saturation or Chromate
364
is the amount of light flux density. It is the unit of measure used when desccribing the amount of light in a room and is expressed in lumens per square foot.
Footcandle (fc)
365
the luminance of a surface reflecting, transmitting or emitting one lumen (lm) of illumination per square foot of area in the direction being viewed or the conventional unit of brightness or luminance.
Footlambert (fl)
366
the amount of light that falls on the areas we want to illuminate:
Lumens per square foot or square meter
presented by formula
Footcandle = lumens/area
Light Flux Density
367
footcandle adequate for halls and corridors.
10fc
368
1 lux to fc
o.09fc
369
footcadle sufficient for areas between work stations such as in offices other than desk areas.
30fc
370
footcandle satisfactory on spaces where office work is being done.
30fc
371
Uniformity of Lighting
The purpose of lighting calculation, by hte footcandle or lux, is to determine the average illumination in a room to a working level condition. This working level condition refers to the height of about ____ above the floor being the approximate height of the table. The average illumination at the working level is directly related to the maximum spacing of the light to the mounting height ratio represented by the formula:
S/mh
where
S = Spacing of Light fixtures
mh = mounting height
75 cm
372
Spacing and MOunting Height Ratio
Direct concentrating
.40
373
Spacing and MOunting Height Ratio
Direct Spreading
1.20
374
Spacing and MOunting Height Ratio
Direct Indirect Diffusing
1.30
375
Semi - direct - indirect
1.50
376
A warehouse will install pendant dome incandescent lamps at a mounting height ratio of 1.50 meters. The lamp will be mounted on a grid measuring 5 x 5m. What is the minimum mounting height of the lamps?
Mounting height is mh = spacing/ratio
mh=5/1.5 = 3.30m
377
When the light on an illuminated area is focused downward coming directly from the lighting fixtures.
Direct Lighting
378
When the predominant light on the illuminated area is fed directly from the lighting units wherein the greater amount of light is obtained from the ceiling through reflection.
Semi-DIrect Lighting
379
A lighting arrangement wherein 5% to 25% of the light is directed downward with more than half of the light focused upward and rflected from the cceiling.
Semi-indirect-lighting
380
when the light is diffused and reflected fro ma wide ceiling area. This kind of lighting produces a soft and subduedeffect due to low brightness and absence of sharp shadows.
indirect lighting
381
are the means by which the switching and dimming functions operates. (eg. wall switches, time switches and dimmers)
Control Devices
382
\_\_\_ is the entire assembly of control and signal initiating equipment together with ther interconnections plus the microprocessors and programmable controllers.
Control System
383
Control Functions:
\_\_\_ is an ON and Off function.
Switch
384
is defined as the whole of the equipment provided for lighting the roadway comprising the lamps luminaires, means of support and electrical installations including other auxilliaries.
Lighting Installations
385
refers to an array of luminaires having a characteristic of light distribution.
Lighting System
386
is a housing for one or more lamps comprsing a body and any refractor, diffuser or enclusre associated with the lamps.
Luminaire
387
is the distance between the edges of the road curbs measured at right angles to the length of the roadway.
Road Width
388
is the distancec measured horizontally between the outer of the column or wall face or lamp post and the center of the luminaires.
Outreach
389
is the horizontal distance between the center of luminaires and the adjacent edge of the road.
Overhang
390
refers to the vertical distance between the center of the luminaire and the surface of the roadway.
Mounting height
391
is the distance between the sucecssive luminaires in an installation.
Spacing
392
streets in residential or warehouse areas and on expree or elevated depressed roadways.
Light or nor pedestrian traffic
393
A secondary business street and some industrial roads.
Medium pedestrian traffic
394
business streets
Heavy Pedestrian Traffic
395
Level of Illumination For Residential
150 lux
396
Martial Law date
September 21, 1972
397
PD 269
Creating the National Electrification Administration (NEA)
398
Electric Distribution System Present Setup
The National Power Corporation
The Meralco
Electric Cooperative INc
399
Ayos
