What is a general use switch intended for?
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For use in the general distribution and branch circuit rated in amperes.
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What is a general use switch intended for?
For use in the general distribution and branch circuit rated in amperes.
What does a Branch Circuit consist of?
What is the purpose of conduits in electrical systems?
To protect and route electrical wiring.
What is a cable?
An electrical conductor that is larger in size.
What is the purpose of the Western Union Long-tie Splice?
To extend the length of wire for outside wiring.
What is a raceway?
An enclosed channel of metal or non-metallic materials designed for holding wires, cables, or busbars.
What is an Aerial Tap?
It is used as a temporary tap, usually done at construction sites.
What is the purpose of legends in electrical design?
To provide a clear understanding of symbols and components used in electrical plans.
How are special outlets counted in the branch circuit?
As one branch circuit and must not be connected to convenience outlets.
What does 'P a g e | 31' refer to?
It indicates a page number in a document.
What is a key feature of conduits according to the Philippine Electrical Code?
They must meet specific standards for safety and functionality.
What should be plotted separately in the floor plan?
Lighting and convenience outlets.
What is a riser diagram?
A visual representation of the vertical distribution of electrical systems in a building.
How does a Cross Joint differ from a plain tap?
It is a combination of two plain taps placed side by side.
What are common types of raceways for household wiring installations?
Conduits, connectors, and other accessories.
What term is used for an insulated stranded wire?
Cord.
What does a junction box typically have?
A blank cover and sufficient space for connections.
Name three examples of good conductors.
Silver, Copper, and Aluminium.
What does ampacity depend on?
The conditions of use and the temperature rating of the conductor.
What is a wire?
An electrical conductor that is smaller in size.
What is the most widely used splice in interior wiring installation?
Western Union Short-tie Splice.
What should be plotted separately in the floor plan?
Lighting and convenience outlets.
What is the primary focus of designing an electrical plan?
To ensure safe and efficient electrical distribution in a building.
What is a stranded wire?
Multiple wires twisted together to form a metallic string.
What is the purpose of a junction box?
To join different runs of raceway or cable, providing sufficient space for connection and branching of enclosed conductors.
Where is a pull box installed?
In one or more runs or raceway.
Why is it important to include safety regulations in an electrical plan?
To prevent electrical hazards and ensure compliance with local codes.
Where should overcurrent protection devices be installed?
On the line or supply side of the equipment being protected.
What is a key component of an electrical plan?
The placement of outlets and switches.
What is the purpose of grounding in an electrical system?
To fix permanently a zero-voltage point in the system.
What is a receptacle?
A contact device installed in an outlet for the connection of an attachment plug.
What is the purpose of a pull box?
To facilitate pulling in the conductors and may also serve to distribute the conductors.
What is the primary purpose of protecting a branch circuit?
To protect it from overcurrent.
What is the purpose of a load schedule in electrical design?
To list the electrical loads and their specifications for proper planning and distribution.
What is an outlet in an electrical wiring system?
A point where current is taken to supply utilization equipment.
What is defined as the portion of supply conductors extending from the street main duct or transformer to the service or switchboard of a building?
Service Entrance.
How can conduits be classified?
As rigid metal, flexible metal, rigid non-metal, and flexible non-metal.
What is the common type of service wire installed by electric power supply companies?
Overhead service.
What is one purpose of electrical conduits?
To provide a means for running wire from one point to another.
What is a requirement for overcurrent protective devices in underground conductors?
They shall be placed in all underground conductors of the protected circuits.
How do conduits protect wires?
By physically protecting them and providing a grounded enclosure.
What is the operating temperature for KHW insulated conductors?
75°C.
Which code provides guidelines for conduits in the Philippines?
Philippine Electrical Code 2017.
What is a special outlet?
An outlet intended for specific equipment that uses a large amount of electricity, such as air conditioning units and refrigerators.
What should be considered when creating a Power Layout Plan?
Load calculations, circuit design, and accessibility.
How should the connections of lighting and outlets be indicated?
By indicating the number of branch circuits.
What is the purpose of a riser diagram?
To visually represent the vertical distribution of electrical systems in a building.
What is an insulator?
Material used to resist the flow of current.
How does a riser diagram relate to a load schedule?
The riser diagram is drawn based on the information provided in the load schedule.
What type of plan is mentioned for lighting layout?
Lighting Layout Plan.
What is a Duplex Cross Joint?
It is a two-tap wire joint turned simultaneously, used under heavy tensile stress.
What is the ampacity rating for a 2.0 mm² copper conductor at 90°C?
25 amps.
What is the smallest circuit breaker size listed in the Philippine Electrical Code?
15 amps.
What is a lighting outlet?
An outlet intended for direct connection to a lamp holder, lighting fixture, or pendant cord terminating in a lamp holder.
What is a Rat Tail or Pig Tail splice used for?
To join two or more conductors inside a junction box without mechanical stress.
What is one method of accomplishing grounding?
Connecting to a buried cold water main.
Can a Circuit Breaker be manually tripped?
Yes, it can be manually tripped and also acts as a circuit switch.
What are butted splices?
Splices made by joining the free ends of conductors together.
What is a third method of grounding?
Connecting to a buried ground plate.
How do 3-way switches differ from single pole switches?
They do not have an on/off position.
What is a riser diagram?
A schematic representation of the vertical distribution of electrical systems in a building.
What does a sample riser diagram typically illustrate?
The layout and connections of electrical components and systems in a vertical format.
What is a Plain Tap Joint used for?
It is used where the tap wire is under considerable tensile stress.
What are the three types of conductors used in electrical systems?
Bare, Covered, and Insulated.
What is the range of circuit breaker sizes according to the Philippine Electrical Code?
15 to 6000 amps.
What should be installed in all branch circuitries for protection?
An overall current protective device.
What advantage does the Aerial Tap provide?
The easy twist facilitates tap wire movement.
What is the primary function of a switch in an electric circuit?
To open or close the circuitry.
Where is the Electric Service Meter typically installed?
Outside the building at the property line wall or electric post.
What is the primary focus when designing an electrical plan?
To ensure safe and efficient electrical distribution throughout a building.
What type of service consists of a raceway extending from the building to the property line?
Underground service.
What is the ampacity rating for a 14 mm² aluminum conductor at 60°C?
55 amps.
What is the role of an electrical meter?
To measure the amount of electricity consumed.
What is the total connected load in the load schedule?
31,700 VA.
How do conduits protect buildings and occupants?
By protecting them from damage caused by the electrical system.
What is the demand factor used in the load schedule?
85%.
What are the two main factors affecting the reliability of electric power?
The electric utility and the building electric system.
What happens to a fuse when there is an overcurrent?
It opens (breaks) the circuit.
What is the ampacity of a 2.0 mm² copper conductor at 90°C?
25 A.
What is the ampacity rating for a 38 mm² aluminum conductor at 60°C?
75 amps.
What is an individual branch circuit designed for?
To supply a single specific item.
What is ampacity?
The current in amperes that a conductor can carry continuously without exceeding its temperature rating.
What is a conductor?
Materials used to flow current.
What are some examples of electrical accessories?
Junction Box, Receptacles, Pull Box, Switches.
What does a pull box typically have?
A blank cover.
What should be considered when designing an electrical plan?
Load calculations, circuit layout, and safety regulations.
When is a Wrapped tap or Tee joint used?
On large solid conductors where wrapping the heavy tap wire is difficult.
What does the Philippine Electrical Code provide for motor current ratings?
A table of motor current ratings.
What are the different kinds of outlets?
What key elements should be included in a riser diagram?
Electrical panels, circuits, load connections, and vertical pathways.
What are the types of switches classified under general use?
What is a key component to consider when drawing a riser diagram?
The correct representation of electrical loads and their connections.
What is a Circuit Breaker?
An overcurrent protective device designed to function as a switch.
What is another function of conduits in relation to buildings?
To protect the wiring system from damage by the building and occupants.
What type of location is suitable for TW insulated conductors?
Dry Location.
What does flexibility of the circuit installation refer to?
The ability to accommodate all probable pattern arrangements and locations of loads for expansion or future development.
What is a fuse?
A current protective device with a circuit opening fusible element that opens when there is an overcurrent.
What does the Power or outlet layout in an Electrical Plan indicate?
The placement and distribution of electrical outlets and power sources.
What is Ampere Trip (AT)?
The maximum current that a circuit breaker will trip the circuit, normally 60% to 100% of ampere frame.
What size of wire is recommended for the circuit protection?
2 - 50 sq.mm THHN Cu wire + 1 - 14 sq.mm TW ground in 40 mm RSC.
What is a Branch Circuit in electrical terms?
It refers to the complete path traversed by an electric current, including the entire house wiring.
What type of insulation does SA conductors use?
Asbestos & Varnish.
What is the first step in designing an electrical plan?
Plot the lightings, convenience outlets, special outlets, and panel board in the floor plan.
What is the operating temperature for THWN insulated conductors?
75°C.
How should lighting and receptacles be supplied with current?
From at least two circuits to prevent total power loss if one line is out.
What is the Volt Ampere requirement for lighting?
100 Volt Amperes each.
What is the ampacity of a 60 mm² copper conductor at 60°C?
100 A.
What is a Power Layout Plan?
A schematic representation of electrical systems and components in a building.
What does a Power Layout Plan typically include?
Locations of outlets, switches, and electrical panels.
Why is a Power Layout Plan important?
It ensures efficient distribution of electrical power and compliance with safety standards.
What is a solid wire?
A single strand of wire.
How should special outlets be counted in the circuit design?
As one branch circuit and must not be connected to the convenience outlet.
What are the two main causes of overcurrent?
Overload in the equipment or conductors, and short circuit or ground fault.
What is required to indicate the number of branch circuits in the plan?
Draw the connections of lighting and outlets.
What must overcurrent protective devices protect?
The wiring, transformer, lights, appliances, and other equipment.
What type of outlet is specifically designed for certain appliances?
Special Outlet.
What is the purpose of the lighting layout plan?
To plot the lighting and outlets in the floor plan.
What device is used to control the flow of electricity in a circuit?
Circuit Breaker.
Name three examples of insulators.
Rubber, Porcelain, and Glass.
What should be considered in an electrical plan design?
Load calculations, circuit placement, and safety codes.
What are the two types of service entrance?
Overhead service and underground service.
What is the purpose of the automatic tripping device in a Circuit Breaker?
To protect the branch circuit from overload and ground fault.
What is a key component of an electrical plan?
The layout of outlets, switches, and fixtures.
When can conductor size be reduced in a circuit or tap?
Unless the smallest wire is protected by the circuit overcurrent devices.
What are 3-way switches used for?
To control lights with two switches.
Which insulated conductor type is moisture and heat resistant with an operating temperature of 75°C?
THW.
What is the Volt Ampere requirement for lighting in the load schedule?
100 Volt Amperes each.
What information does a Riser Diagram provide in an Electrical Plan?
It illustrates the vertical distribution of electrical systems.
What is a major advantage of a fuse over a circuit breaker?
Fuses are more reliable and stable, often lasting for years.
What is a good practice regarding lighting and receptacles in a circuit?
Lighting and receptacles should not be combined in a single circuit.
How does the cost of a fuse compare to that of a circuit breaker?
Fuses are much cheaper than circuit breakers.
What should space allocation consider?
Easy maintenance, ventilation, expandability, centrality, and limited access.
What is the characteristic of a cartridge type fuse?
It is enclosed in an insulating fiber tube.
What is the characteristic of a plug fuse type?
It is enclosed in a porcelain cap.
What is the demand factor used in the calculations?
85%.
What is the multiplier for the largest motor load when determining wire size?
Multiply by 0.25.
What information is typically included in a load schedule?
Details about the electrical loads, including their types, ratings, and locations.
What do overcurrent protective devices do?
They open the circuit or disconnect the line when the current rating capacity is exceeded.
What is the largest circuit breaker size listed in the Philippine Electrical Code?
6000 amps.
What is a convenience outlet?
A device that establishes connection between the conductor of a flexible cord and the conductors connected to the receptacle.
What is the function of a panel board in electrical systems?
To distribute electrical power to various circuits.
How should all equipment be protected?
In accordance with its current carrying capacity.
Which types of conductors have a temperature rating of 75°C?
Types RHW, THHW, THW, THWN, XHHW, USE, ZW.
What is a common feature of lighting outlets?
They are designed to connect lighting fixtures.
What happens to a circuit breaker after it trips due to an overcurrent?
It can be reset and used again after correcting the fault.
What role do load calculations play in electrical plan design?
They determine the appropriate size and number of circuits needed.
What is the total demand current calculated at the 85% demand factor?
105.18 A.
What does reliability and efficiency of service depend on?
The wiring system.
What is the operating temperature for XHHW insulated conductors?
90°C.
How can the position of a circuit breaker be easily detected?
It can be closed, tripped, or open right at the handle.
What is the ampacity rating for a 175 mm² copper conductor at 75°C?
405 amps.
What is the ampacity of a 14 mm² aluminum conductor at 75°C?
65 A.
What is the role of the final overcurrent device in a Branch Circuit?
It protects the circuit and connects to the outlets.
What are the two types of fuses?
Cartridge type and plug fuse type.
What is the ampacity of a 38 mm² copper conductor at 75°C?
90 A.
What is the ampacity of a 100 mm² aluminum conductor at 90°C?
225 A.
What is the significance of safety in circuitry design?
It prevents hazards and ensures user protection.
How is the circuit breaker size determined?
It may equal the wire ampacity or the next size lower.
Why is space allocation important in circuit design?
To ensure proper installation and functionality of components.
What multipliers are used for the largest motor load in wire size and protection?
Multiply by 0.25 for wire size and 1.5 for protection.
How does a riser diagram relate to a load schedule?
The riser diagram is drawn based on the information provided in the load schedule.
What becomes the source of voltage in a panel board?
The busbars, when looking upstream from the overcurrent devices.
What is splicing in electrical wiring?
The process of combining two lengths of wires so they can carry a current.
Why should the grounding connection not be broken or fused?
To maintain a solid and uninterrupted connection to the ground.
Where is a general use snap switch typically installed?
In flush device boxes or an outlet box cover.
When is a Y-Splice typically used?
On small cables where the strands are flexible and can be wrapped in one operation.
What are the main components of an Electrical Plan for a residential building?
What is the ampacity rating for a 100 mm² aluminum conductor at 75°C?
200 amps.
What do general purpose branch circuits supply?
Outlets for lighting and appliances, including convenience receptacles.
What is a key limitation of a fuse compared to a circuit breaker?
A fuse is a single pole device that can only protect one electric line.
What is the Volt Ampere requirement for convenience outlets?
180 Volt Amperes each.
What does economy refer to in electrical installations?
Both the initial cost and the operating cost.
What is the application provision for AVA insulated conductors?
Dry Location.
What is the spare load requirement in Volt Amperes?
1500 Volt Amperes.
What are some considerations for good circuitry design?
What is the Volt Ampere requirement for lighting in the load schedule?
100 Volt Amperes each.
What is the Volt Ampere requirement for a convenience outlet?
180 Volt Amperes each.
What rule should be followed when selecting wire size?
Always choose the next size up rule.
What is the ampacity of a 175 mm² copper conductor at 90°C?
400 A.
What type of circuit breaker is recommended?
60 AT/100AF, 2P, Bolt-On Type CB.
Why is it important to follow safety codes in electrical plan design?
To prevent electrical hazards and ensure compliance with regulations.
What should be ensured about the assembly of overcurrent protective devices?
They should be readily assembled and protected from physical damages and away from easily ignited materials.
What is the purpose of an isolating switch?
To isolate an electric circuit from the source of power.
What is the maximum operating temperature for THHN insulated conductors?
90°C.
How many poles can a circuit breaker have?
It can have 1, 2, or 3 poles.
What is the ampacity rating for a 22 mm² copper conductor at 90°C?
80 amps.
What is the purpose of an appliance branch circuit?
To supply outlets intended for feeding appliances.
What is Ampere Frame (AF)?
The maximum current that a circuit breaker can withstand for a long period of time.
What is the most common type of circuit protective device used in house wiring?
Fuse.
What is the Volt Ampere requirement for a refrigerator?
500 Volt Amperes each.
What are the key factors to consider for energy considerations?
Energy laws, budget, energy conservation techniques, and energy control.
Which conductor type has the highest ampacity at 90°C for 60 mm²?
255 A (Copper).
What type of insulation is used for thermoplastic heat resistant conductors?
Thermoplastic.
What should not be allowed in combination with switch and receptacle outlets?
Combination switch and receptacle outlets.
What is the Volt Ampere requirement for a refrigerator?
500 Volt Amperes each.
What is the total connected load in the example provided?
8280 Volt Amperes.
What rule should be followed when selecting wire size?
Always choose the next size up rule.
How do you calculate the total ampere of the design?
Add all branch circuits' Volt Ampere values and divide by 230 volts.
What dual function does a circuit breaker serve?
It acts as both a switch and an overcurrent protective device.
What is the ampacity rating for a 60 mm² copper conductor at 90°C?
120 amps.
Name another method of grounding.
Connecting to a ground rod.
What does 'Trip' or 'Tripping' refer to in electrical terms?
The cutting-off or disconnection of the current supply.
What is a tap joint in electrical wiring?
A junction that joins a branch conductor to a continuous main wire.
Is a fuse a one-time or reusable device?
It is a one-time protective device that must be replaced after a fault is cleared.
What types of conductors are listed for 60°C rating?
TW, UF.
What are some standard Ampere Trip sizes according to the Philippine Electrical Code?
15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100, 110, 125, 150, 175, 200, 225, 250, 300, 350, 400, 450, 500, 600, 700, 800, 1000, 1200, 1600, 2000, 2500, 3000, 4000, 5000, 6000.
What is the size of the circuit breaker protection calculated?
126.7 Amp or 141.74 Amp.
What should be avoided when connecting building lights?
Connecting all building lights on a single circuit.
What maintenance requirement does a circuit breaker have that a fuse does not?
Circuit breakers require maintenance and periodic testing due to their moving parts.
What are the classifications of branch circuits?
General purpose branch circuit, appliance branch circuit, and individual branch circuit.
How does reliability affect circuit design?
It ensures consistent and efficient service.
What types of conductors are listed for 75°C rating?
RHW, THHW, THW, THWN, XHHW, USE, ZW.
How do you calculate the ampere value of each branch circuit?
Divide each branch's Volt Ampere by 230 Volts.
How is the circuit breaker size determined?
It may equal the wire ampacity or the next size lower.
What is the purpose of the Lighting layout in an Electrical Plan?
To show the arrangement and types of lighting fixtures.
What does safety of the circuitry imply?
Independent service can be used as backup for normal services instead of emergency equipment.
What type of circuit breaker is suggested for use?
125 AT/200AF, 2P, Bolt-On Type CB.
What is included in a Load Schedule within an Electrical Plan?
Details about the electrical load requirements for different circuits.
What is the ampacity rating for a 250 mm² aluminum conductor at 90°C?
345 amps.
What is the significance of the colors in the load schedule?
They indicate how the process is done.
What is the purpose of preparing a Load Schedule?
To identify the sizes of wire and circuit breakers needed in the design.
What rule should be followed when selecting wire size?
Always choose the next size up rule.
How do you calculate the ampere value of each branch circuit?
Divide the Volt Ampere of each branch by 230 Volts.
Why is economy a consideration in circuit design?
To manage costs effectively while maintaining quality.
What should be done to determine the total ampere of the design?
Add all the branch circuits' Volt Ampere values and divide by 230 volts.
What should be done to determine the size of conduit?
Use the table of conduit specified in the Philippine Electrical Code (PEC).
What does a fuse consist of?
A fusible link or wire that melts at low temperature.
How should lighting and outlets be plotted in the electrical plan?
They must be plotted in separate sheets.
How do you calculate the ampere value of each branch circuit?
Divide each branch's Volt Ampere by 230 Volts.
Why is flexibility important in circuit design?
It allows for adjustments and modifications as needed.
How is the circuit breaker size determined?
It may equal the wire ampacity or the next size lower.
What is the spare Volt Ampere value in the load schedule?
1500 Volt Amperes.
What does energy consideration involve in circuit design?
It involves optimizing energy usage and efficiency.
What is the multiplier for the largest motor load for protection?
Multiply by 1.5.
What is the size of wire recommended for the load?
2 - 14 sq.mm THHN Cu wire + 1 - 8.0 sq.mm TW ground in 25 mm RSC.
What is the final step in the electrical plan design process?
Using the load schedule to draw the riser diagram.
