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TASK TITLE: Wired Devices and Electrical Service
POS #: 1100 & 1300
TASK: Install & estimate size and cost of Services, Install sub panel & Change old service to new to the N.E.C.
Install a hard wired smoke detector and door bell system.
PURPOSE: To Estimate and Install a Complete Electrical Service According to the N.E.C. Standards.
TASKS:
|1100 |Wired Devices |
|1101 |Install a hard wired smoke detector. |
|1102 |Install a door bell system |
| | |
|1300 |Electrical Service |
|1301 |Install a 100 amp overhead service. |
|1302 |Identify a 100 amp underground service. |
|1303 |Install sub-panel w/ circuits onto an existing panel. |
REVISION: 2019
|ENGLISH LANGUAGE ARTS |
|CC.1.2.11-12.J Acquire and use accurately general academic and domain-specific words and phrases, sufficient for reading, writing, speaking, and |
|listening at the college and career readiness level; demonstrate independence in gathering vocabulary knowledge when considering a word or phrase |
|important to comprehension or expression |
|CC.1.3.11-12.I Determine or clarify the meaning of unknown and multiple-meaning words and phrases based on grade level reading and content, |
|choosing flexibly from a range of strategies and tools. |
|MATH |
|CC.2.1.HS.F.4 Use units as a way to understand problems and to guide the solution of multi-step problems. |
|CC.2.1.HS.F.6 Extend the knowledge of arithmetic operations and apply to complex numbers. |
|READING IN SCIENCE & TECHNOLOGY |
|CC.3.5.11-12.B. Determine the central ideas or conclusions of a text; summarize complex concepts, processes, or information presented in a text by |
|paraphrasing them in simpler but still accurate terms. |
|CC.3.5.11-12.C. Follow precisely a complex multistep procedure when carrying out experiments, taking measurements, or performing technical tasks; |
|analyze the specific results based on explanations in the text. |
|WRITING IN SCIENCE & TECHNOLOGY |
|CC.3.6.11-12.E. Use technology, including the Internet, to produce, publish, and update individual or shared writing products in response to |
|ongoing feedback, including new arguments or information. |
|CC.3.6.11-12.F. Conduct short as well as more sustained research projects to answer a question (including a self generated question) or solve a |
|problem; narrow or broaden the inquiry when appropriate; synthesize multiple sources on the subject, demonstrating understanding of the subject |
|under investigation |
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*ACADEMIC STANDARDS *
|READING, WRITING, SPEAKING & LISTENING |
|1.1.11.A Locate various texts, assigned for independent projects before reading. |
|1.1.11.D Identify strategies that were most effective in learning |
|1.1.11.E Establish a reading vocabulary by using new words |
|MATH |
|2.2.11.A Develop and use computation concepts |
|2.2.11.B Use estimation for problems that don’t need exact answers |
|SCIENCE |
|3.1.12.A Apply concepts of systems, subsystems feedback and control to solve complex technological problems |
|3.1.12.B Apply concepts of models as a method predict and understand science and technology |
|ECOLOGY STANDARDS |
|4.2.10.A Explain that renewable and non renewable resources supply energy and material. |
|4.2.10.B Evaluate factors affecting availability of natural resources. |
|CAREER & EDUCATION |
|13.1.11.A Relate careers to individual interest, abilities, and aptitudes |
|ASSESSMENT ANCHORS |
|M11.A.3.1.1 Simplify expressions using the order of operations |
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STUDENT
The student will be able to estimate and install a complete electrical service according to the National Electric Code’s standards.
TERMINAL PERFORMANCE OBJECTIVE
Given all the electrical tools and materials required, the student will estimate and install an electrical service to 100% accuracy and in accordance with the National Electric Code.
SAFETY
• Always wear safety glasses when working in the shop.
• Always check with the instructor before turning power on.
• Always use tools in the correct manner.
• Keep work area clean and free of debris.
• Never wire a project without the correct wiring diagram.
RELATED INFORMATION
1. Attend lecture by instructor.
2. Obtain handout.
3. Review chapters in textbook.
4. Define vocabulary words.
5. Complete all questions in this packet.
6. Complete all projects in this packet.
7. Complete K-W-L Literacy Assignment by Picking an Article From the
“Electrical Contractor” Magazine Located in the Theory Room. You can pick any article you feel is important to the electrical trade.
EQUIPMENT & SUPPLIES
1. Safety glasses 12. Duplex receptacles
2. Hammer 13. Switches
3. Screw driver 14. Device boxes
4. Awl 15. Grounding screws
5. Wire strippers 16. Wire staples
6. Side cutters 17. Romex connectors
7. Cable rippers 18. Device covers
8. Lineman pliers 19. Wood screws
9. Needle nose pliers 20. Electrical tape
10. Romex cable 21. Service panel/meter base
11. Wire nuts 22. Service entrance cable
PROCEDURE
CC.2.1.HS.F.4 Use units as a way to understand problems and to guide the solution of multi-step problems.
CC.3.5.11-12.C. Follow precisely a complex multistep procedure when carrying out experiments, taking measurements, or performing technical tasks; analyze the specific results based on explanations in the text.
1.6.11A Listen to others, ask questions, and take notes
3.4.12.B Apply energy sources and conversions and their relationship to heat and temperature
1. First determine what the function of the project is following the schematic diagram in this packet.
2. Next draw the schematic and wiring diagram for the project. This will be your “blueprint” to follow during the wiring process. (See example)
3. Next list all the materials you will need to complete the project.
4. Using a screw driver and wood screw install the device box. The SUGGESTED height of a receptacle is 18”. (Consult the National Electric Code for any specific requirements.)
5. Using a screw driver install the romex connectors into the device box.
6. The next step is to run the romex cable to each box. Using the screw driver, secure the cable in the romex connectors. (Run wires in studs, neatly, to each device box.
7. Using the cable ripper’s, strip off the insulation from the romex cable.
8. Using the side cutters, cut away excess insulation from the romex cable.
9. Using the wire strippers, strip off one inch of insulation from each conductor.
(NOTE: The conductors should extend from the device box a minimum of six (6) inches.)
Now you are ready to install the devices.
10. First, using the required tools, secure the grounds to the box and the device.
11. Using the lineman pliers, perform a pigtail splice to secure the grounds to each other.
12. Install a wire nut onto the splice and tighten.
13. Following the wiring diagram, install the black wire onto the “gold” or “brass” colored screw.
14. Following the wiring diagram, install the white wire onto the “silver” or “aluminum” colored screw.
FIELD NOTES
a. IT IS A GOOD HABIT TO WRAP ELECTRICAL TAPE AROUND THE DEVICE AFTER THE WIRES ARE CONNECTED AND YOU ARE READY TO INSTALL THE DEVICE INTO THE HANDY BOX. THIS WILL HELP IN INSULATING THE WIRES SO THEY DO NOT COME IN CONTACT WITH THE METAL HANDY BOX.
15. Using the device screws and screw driver secure the receptacle into the device box and install cover plate. (NOTE: The common way to install a receptacle is with the ground facing up. This is a required procedure when taking the N.O.C.T.I. and Journeyman’s tests.)
16. Using the required electrical tools, strip off the insulation from the romex cable and strip of the insulation from each conductor.
17. Hook up the power wire to the power supply. (Black to Black, White to White, and the Ground to Green.)
18. The final step is to ask the instructor to evaluate the project. The instructor will turn the power on if the project is safe after inspection.
19. When the project is approved, turn in the schematic and wiring diagram with the material list for final approval.
Load Balancing
1. Now that you have installed the branch circuit conductors and breakers, you must balance the load.
2. Conductors cannot be connected to a panelboard by attaching each one as you come to it.
3. The arrangement or sequence of attaching conductors to the panelboard is determined by the arrangement of the bus bars in the panelboard, whether the circuits are 240 volts or 120 volts, and the need to balance the load on the phase conductors.
4. Bus bars are installed into panelboards in one of several ways. Most of the time, the bus bars are run in a vertical configuration. In one arrangement, a split-bus panelboard is used that has all the 240-volt circuits in the upper section and the 120-volt circuits in a lower section.
5. Another type of split-bus panelboard uses one main circuit breaker to feed one set of branch circuits and a second main circuit breaker to feed a second set. In many cases, panelboards are designed so that any two adjacent terminals can be used to provide 240-volt service. This arrangement also means that two 120-volt circuits attached to adjacent terminals are connected to different phase conductors.
6. Since there are so many panelboard layouts, you must look at the panelboard to see how it is set up for 240-volt service, and you must be sure you get the conductors for 240- volt circuits connected to the proper terminals.
7. Loads that are connected to a panelboard should be divided as evenly as possible between the supply conductors.
8. This process of equalizing the load is commonly referred to as load balancing. The purpose of load balancing is to reduce voltage drop that results from overloading one side of the incoming service. It also prevents the possibility of overloading the neutral. A perfectly balanced load between the supply conductors reduces current flow in the neutral to zero.
9. Load balancing is no problem for 240-volt circuits on a three-wire, single-phase system since the load has to be equal on each phase conductor. However, the 120- volt circuits are a different matter. These must be connected in such a way that the loads tend to equalize. Generally speaking, the simplest way to balance the load on a panelboard is to connect an equal number of branch circuits to each phase conductor. But this method does not necessarily give you a balanced load as will be evident.
10. As you can see, the indiscriminate connection of branch circuits without consideration of their loads can cause you to end up with an unbalanced condition. On the other hand, you can connect the circuits so that one with a heavy load is offset by one with a light load, which does result in the balanced condition. Most of the time, you should be able to connect half of the lighting circuits and half of the appliance circuits to each phase conductor to give you a reasonably well-balanced load.
11. Spare circuits should also be equalized
12. There is one more thing to consider: When there are appliance circuits where the loads are known to be heavy, these circuits must be divided between the phase conductors.
REFERENCE PAGES
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TROUBLESHOOTING AND REPAIR OF INTERIOR WIRING SYSTEMS Electrical troubleshooting is an important part of your job. Your ability to find a faulty condition quickly can play an important part in shortening the downtime caused by failure. To find faulty conditions in circuits, you must do some inspecting, some calculating, and some instrument testing. A few moments spent studying the circuit diagrams before you start actual troubleshooting will simplify the task of isolating the trouble. If a circuit fails to function, use logic when you check for the fault. The trial-and-error method of finding faults in circuits is inefficient and time-consuming.
The first step to take in troubleshooting circuits is to inspect the circuit visually. Check for loose connections, loose wires, abraded wires, and loose fittings. An overloaded circuit is a serious problem.
Many times the electrical demand on a circuit is so great that the circuit fuses blow or the circuit breakers trip. In some cases, the wrong fuses or circuit breakers are used, and the wires overheat and burn off the insulation. This condition causes shorts and grounds and sets up potential fire hazards.
OPEN, SHORTED, AND GROUNDED CIRCUITS
An OPEN CIRCUIT occurs in a wiring system when one or more conductors in a circuit are broken or otherwise separated. An open circuit is determined by the failure of a part or all of an electrical circuit to operate, even though the fuses may not be blown. Use the following maintenance procedures for locating the source of the trouble: 1. Initially, you should make a visual check for a broken or loose connection at the first dead (nonoperating) outlet in the circuit. If a defective connection is found, tighten or repair the connection.
Panelboards
The service entrance terminates in the service equipment or in a panelboard. The panelboard may be used for lighting and power branch circuits. A distribution panel, as the name implies, serves as a center or point in the electrical system where power is fed to the branch circuits. A distribution panel consists mainly of a metal cabinet that houses bus bars and individual circuit protective devices. The protective devices (fuses or circuit breakers) protect me circuits against excessive current flow. Panelboards must be rated at least as high as the feeder capacity required for the load. Panelboards are marked by the manufacturer with the voltage, current rating, and number of phases for which they are designed. This information, plus the manufacturer's name or trademark, is not to be obstructed by interior parts or wiring after the panelboard is installed. According to the NEC(c), lighting and appliance panelboards cannot have more than 42 overcurrent devices besides the mains. Two-pole and three-pole circuit breakers are connected as two and three overcurrent devices, respectively.
According to the NEC(c), each lighting and appliance panelboard must be protected from current flow on the supply side by not more than two main circuit breakers or two sets of main fuses that have a combined rating no greater than that of the panelboard. This protects not only the feeders but also the panelboard. The panelboard does not need individual protection if the panelboard feeder has overcurrent protection no higher than the panelboard rating. The total load on any single overcurrent device in a
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Plug type of fuse.
panelboard must not exceed 80 percent of its capacity where, in normal use, the load continues for 3 hours or longer to prevent overheating of the conductor. Panelboard cabinets must be grounded. A terminal bar must be provided for attachment of feeder and branch circuit equipment-grounding conductors where nonmetallic raceway or cable is used. This terminal bar must be bonded to the cabinet, but not to the neutral bar except in service equipment.
Three-phase panelboards supplied by a four-wire, delta-connected system that has the midpoint of one phase grounded must have the higher voltage-to-ground conductor or bus bar marked. This high-voltage conductor should have an orange outer finish or be clearly tagged. The identification is required at any point where a connection can be made and the neutral conductor is also present. The phase arrangement on a three-phase panelboard is A, B, C, from left to right, or top to bottom when viewed from the front. The B phase will be the phase that has the higher voltage-to-ground.
There are two basic types of panelboards: fuse panels and circuit breaker panels. Fuse panels, as the name implies, contain fuses for protection of each circuit. Fuse panels are designed in a variety of ways. These designs vary in size, capacity (amperage and voltage), and type of installed fuses. The capacity of the panel is based on the ampacity of the bus bars of the panel. The number of bus bars is determined by whether the panel is single-phase or three-phase. Fuse panels are designed for plug fuses, cartridge fuses, knife-blade fuses, or a combination of these. Fuse panels use an Edison-base fuse that screws into a socket similar to the medium-based light socket. Fuse panels still exist but are not very common. Fuse panels are not to be installed either for new work or as a replacement panel unless they have been modified to accept Type S fuses.
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Adapter and Type S fuses.
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Ferrule type of fuse. The other type of fuse you will be dealing with, as a CE, is the cartridge fuse. There are two types: the ferrule and the knife blade. Both types are available with replaceable or nonreplaceable fuse links. Ferrule fuses are available in ampere ratings from 0 through 60. Fuse panels that use the ferrule type of fuse have specially designed fuse clips in which only ferrule types will fit. Fuse diameter and length increase as amperage and voltage increase. Ferrule fuses are used in circuits up to 600 volts. Figure 5-63 shows a typical ferrule type of fuse.
Fuse panels that provide distribution for high-capacity circuits use knife-blade fuses for protection. The fuse clips are especially designed to receive knife-blade fuses only. Knife-blade fuses are available in ampere ratings of 61 through 6,000. The maximum voltage rating for knife-blade fuses is 600 volts. Figure 5-64 shows a typical knife-blade fuse.
Two factors must be considered when fuses for circuit protection are to be selected. These are the total current flow and the voltage of the circuit in which the fuse is to be installed. Since the purpose of the fuse is to protect the circuit, it must be the weakest point in the circuit. Thus the fuse used should be rated no higher than the lowest rated component to be protected. Before installing a fuse in a panel; check the condition of the
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Knife-blade fuse. Fuse holder or clips. These must be clean and hold the fuse firmly.
One of the newer types of protective devices, used more often than fuses because of the way it reacts to an overload, is the circuit breaker. A circuit breaker trips on an overload but can be reset to complete the circuit again without having to be removed or replaced. Circuit breakers are classed according to their operating principle. They may be thermal, magnetic, or a combination of thermal and magnetic. Figure 5-65 shows typical circuit breakers with one, two, and three poles. Multipole breakers are designed to open all ungrounded conductors in a circuit at the same time.
A thermal type of circuit breaker has a bimetallic element within the breaker that responds to temperature change. The bimetallic element is made by fusing together two strips of dissimilar metal. Each strip has a different expansion rate when heated. Current flowing through the breaker generates heat, which increases as the flow increases. The heat causes the bimetallic element to bend and act against a latch. The breaker mechanism is adjusted so that when the current flow reaches a set level, the element bends enough to trip the latch. This action opens a set of contacts to break the circuit. The thermal type of circuit breaker is commonly called a time lag breaker because the breaker
Typical circuit breakers.
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does not open immediately when an overload occurs. The bimetallic element requires a short time (length depends on the size of the overload) to respond to the heat generated by the overload current.
A magnetic type of circuit breaker responds instantaneously when an excess of current flows through the breaker. A small electromagnet is used to actuate the breaker mechanism. Whenever a predetermined amount of current flows through the electromagnet, enough magnetic flux is created to attract a small armature. As the armature moves, the breaker mechanism trips and opens the circuit.
The thermal-magnetic circuit breaker, as the name implies, combines the features of both the thermal and the magnetic types. Of the three, the thermal-magnetic circuit breaker is preferred for general use. A small overload actuates the bimetallic strip to open the circuit on a time delay, while a large overload or short circuit actuates the magnetic trip to open the circuit instantaneously. Circuit breakers are rated in amperes and volts the same as fuses and you select them on the same basis. Circuit breakers are sealed units and no attempt should be made to repair them or to adjust the ampere capacity. A defective breaker must be removed and replaced.
Circuit breakers that are to be used in circuits that may pose an added hazard to the user are made with an extra safety feature. This breaker is called a ground fault circuit interrupter (GFCI). It is a thermal-magnetic breaker with an additional internal circuit that detects a current leak from the hot wire to ground and opens the breaker if that current reaches a set amount. This leakage cannot be more than 5 (± 1) milliamperes (thousandths of an ampere) to ground. Most of these breakers have a test button that can be used to check the GFCI to see if it will trip when there is a fault.
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Quite often the panelboard is not connected until the interior wiring is done and the receptacles, switches, and fixtures have been installed. The method of attaching circuit conductors is based on conductor size and type of terminals on the panelboard. Small conductors, No. 10 and smaller, are normally looped around a screw type of terminal. Larger conductors may need to have terminal lugs, attached so the connection can be made to screw terminals. Pressure types of terminals are often provided for larger conductors, neutral conductors, and equipment-grounding conductors.
Conductors should be connected in a neat and professional manner. In many cases, conductors are connected with little excess wire. Conductors brought in through the sides of the cabinet are connected directly to the overcurrent device. Those brought in from the top or bottom of the cabinet are bent neatly opposite the fuse or circuit breaker to which they are to be attached and cut just long enough to make a good connection, as shown in figure 5-66. However, many experienced electricians feel that this system of connecting conductors is not necessarily the best, even though it presents the most uncluttered look and leaves more space around each conductor. These electricians usually try to leave an end on each conductor that is equal to the height plus the width of the cabinet. Each conductor is run along the panel and looped back 180 degrees before being connected to its fuse or circuit breaker. Little added material is needed, and the extra length on the conductor permits it to be switched to another terminal on the panel if desired. Also, in the case of conductor breakage near the terminal, the conductor can be reconnected easily. The ungrounded conductors in a fuse panelboard are connected directly to terminals on the bus bars. In a circuit breaker panelboard, the underground conductors are usually connected to the circuit breaker. The circuit breaker is then inserted in the panelboard. In most cases, the breaker is snapped into place and is held by spring tension. Sometimes breakers are held in the panelboard by a screw.
• SINGLE POLE, SINGLE THROW BREAKER (LEFT)
• DOUBLE POLE, SINGLE THROW BREAKER (RIGHT)
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VARIOUS TYPES OF SERVICE INSTALLATIONS
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UNDERGROUND SERVICE WITH LATERALS
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CLEARENCES FOR OVER HEAD SERVICE
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CLEARENCES FOR OVERHEAD SERVICES
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EXAMPLE OF AN N.E.C. VIOLATION
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CLEARENCES ACCORDING TO THE N.E.C.
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CLEARENCES ACCORDING TO THE N.E.C.
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CLEARENCES ACCORDING TO THE N.E.C.
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WHAT NOT TO DO WITH A SERVICE MAST
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CODE REQUIREMENTS
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CODE REQUIREMENTS
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GROUNDING REQUIREMENTS
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GROUNDING REQUIREMENTS
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GROUNDING REQUIREMENTS
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VARIOUS GROUNDING CLAMPS
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CODE REQUIREMENTS
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CODE REQUIREMENTS
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CODE REQUIREMENTS
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CODE REQUIREMENTS
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CODE REQUIREMENTS
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200 AMP METER BASE WITH HUB ASSEMBLY
Overhead
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Underground
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CODE REQUIREMENTS
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Sub Panel
Section
PROCEDURE
CC.1.2.11-12.J Acquire and use accurately general academic and domain-specific words and phrases, sufficient for reading, writing, speaking, and listening at the college and career readiness level; demonstrate independence in gathering vocabulary knowledge when considering a word or phrase important to comprehension or expression
CC.3.5.11-12.C.Follow precisely a complex multistep procedure when carrying out experiments, taking measurements, or performing technical tasks; analyze the specific results based on explanations in the text.
Installing a Sub Panel
• In this situation, the original panel was full to the point of some circuits that were added since construction having to be ‘double-lugged’ under existing breakers.
• The customer had just purchased the house, and he needed to renovate his basement in order to accommodate future expansion.
Planning
• The first step should always be planning, as a project such as this is fairly complex. Take the time to think through the necessary steps to complete the job, ensure that you have the appropriate tools and materials, and that all appropriate safety requirements are being followed.
• Good lighting is critical when working on this type of project, so I would recommend that you arrange for an external light source, such as a good battery operated light, or a portable generator outside.
• Run in an extension cord to a portable work light, or a trouble light. This will allow you to work in the original panel to make the required changes with the main breaker off, which will de-energize the bus bars in the panel.
• Look at the area you have to work with and decide where you are going to mount the subpanel. Keep in mind that you don’t have to install it right beside the original panel if space is an issue.
• If the planned renovations are in the opposite end of the house from the original panel, you may want the subpanel closer to that area. This would result in using a longer length of the heavier, more expensive wire to feed the sub, but you would use less wire in all the branch circuits added in the renovation.
• In this case, the service board has plenty of room to the left of the original panel, and the room that the panel is in doesn’t have a finished ceiling, so running new wires to the sub will be easy to do from anywhere in the basement that the renovation will take place.
• Now prepare the panel for mounting by removing all covers.
Preparing the Subpanel
• Mount the panel at a comfortable height for working on, and for re-setting breakers etc. A good rule of thumb is about 5 feet from the floor to the center of the panel.
• Use the top key-hole screw slot in the back of the panel to hang it and using a level, hold the panel in place, and use the remaining mounting holes to secure the panel to the mounting board. (At least 4-#10 wood screws for a panel this size).
Removing Circuits
• Choose to remove a 3-wire (two 15A breakers) that feed some kitchen counter split receptacles, and two 2-wire branch circuits (as these were double-lugged already) to make room for the 2 pole 40A breaker to feed the new subpanel.
Cutting in the Cables
• Next, cut in the cables that were removed from the existing panel into the new tub, and the new sub feed cable interconnect between the two panels.
• Use #8 AWG 3-conductor NMD-90 wire for the interconnect (Range cable). Make sure you use approved cable connectors where you bring cables in through the knock-outs in the panels.
• Notice that the panel was installed with the main breaker compartment at the bottom. This was to accommodate the existing and the future branch circuits that will enter the subpanel in the top and the sides of the panel.
• Choose the circuits that have the wires long enough to cut into the new subpanel without spicing.
• This particular panel is a Westinghouse ‘Nova-Line’ panel, and Westinghouse has since been bought out by Cutler-Hammer.
• The breakers used in this panel are called ‘quads’, and ‘tandems’ or DNPL style. They are a ‘push-in’ breaker, as opposed to a ‘bolt-in’ style.
• These panels will also accommodate a ‘BR’ style breaker, but they take up one whole breaker space alone, as they are twice as wide.
• One thing to check is that some of the older Westinghouse breakers will not fit in the new Cutler-Hammer panels, as the mounting tabs are slightly different.
• A new Cutler-Hammer breaker will fit in the Westinghouse panel, but in the case here, the breakers I removed from the original will not fit in the new tub.
• Use a 15-40-40-15 DNPL breaker to feed the subpanel. The two 40A breakers in the middle (split across both hot busses of the panel) will feed the new sub, and the two 15A circuits on the outside will be used to feed the existing circuits that will now have their own breakers, instead of being double-lugged (which is against any and all rules that I’m aware of!).
• This is a panel with a main breaker, and space for 20 BR style breakers, or 40 circuits in the DNPL style. This will give us more than enough breaker space for the planned renovation, as this subpanel is bigger than the original.
• A main breaker is not required in this subpanel because a disconnect exists right beside it in the original panel. It makes no difference whether you feed the buss bars in the subpanel via main lugs, or through a main breaker; the results are the same.
• The 100Amps main is providing over-current protection for the buss bars, and not any of the branch circuits, and the subpanel current is limited to 40Amps by the subpanel feed breaker in the main panel.
Making Your Connections
• At this point, you could make your connections to the sub feed breaker in the main panel, and re-install the panel cover.
• Leave the sub feed breaker off, but now you could turn the main breaker in the original panel back on, and restore power to the house and get the lights, heat, etc. back working again.
• When installing cables into a panel, connect the bare ground wires first, then the neutral (white) wires to the neutral buss, and finally, install the breakers and connect the hot wires (red or black) to the breaker lugs.
• Always take the time to make the wires look neat and orderly, as it not only looks good, but saves time tracing wires, if necessary, in the future.
• The same goes for the connections to the main lugs (or in this case the main breaker) in the subpanel. Make sure that you bring the sub feed cable into the main breaker compartment of the subpanel.
Neutral Bonding Jumper
• This would be a good time to talk about the neutral bonding jumper.
• In most panels you will find that the neutral buss bar (the common bar that is mostly isolated from the panel case), has either a long brass machine screw, or a metal strap of some kind that connects the neutral bar to the panel case, or ground.
• In a subpanel, the neutral must be totally isolated from ground, so you must remove this screw or strap. The neutral and the ground can only be bonded in one location in a residential service, and that is in the main panel.
• The sub-feed cable then connects like this:
o Bare ground wire to a case ground lug, the white neutral wire to an appropriately sized lug on the now isolated neutral bar, and the red and black hot wires to the lugs of the main breaker in the subpanel.
• As is the case in the main panel, you are reverse feeding the main breaker, which then feeds power through to the panel’s hot buss bars that the branch circuit breakers connect to. (Clear as mud, or did I lose you now?)
Final Connections
• Now connect the branch circuit wires in the same order:
• Bare grounds to the panel case, white neutrals to the neutral bus bar, then install your branch circuit breakers and connect the hot wires to the breaker lugs.
• Once all the connections are made, you can install the main compartment barrier, and then remove the appropriate knockouts in the panel cover, and install it.
• Turn on the sub-feed breaker in the main panel, followed by the subpanel main, and then the branch circuit breakers.
• If no sparks fly, and the circuits that you moved to the subpanel now work, you’ve done a great job, and you now have the room you need to accommodate the additional circuits that will be added during the upcoming renovation project.
Labeling the Panel
• The final step is to label the panel in order to identify which breaker feeds what; a step that is all too often over-looked, but any good inspector will catch you on this one, and make you label the circuits before giving his/her final acceptance
M.L.O. Panel (Main Lug Output)
Notice there is no Main in the panel
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6 Circuit Sub Panel
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SERVICE PROJECTS
Note: If you still owe projects from level 1 task’s, you may add them onto the service panel projects in order to catch up. This means you can do multiple projects and complete 1 blue print and 1 material list, but receive credit for multiple projects.
AFTER EACH PROJECT IS COMPLETE, THE STUDENT WILL DEMONSTRATE THE PROPER USE OF THE THERMAL IMAGING CAMERA TO CHECK FOR HEAT ZONES CAUSED BY INFERIOR CONNECTIONS. THE STUDENT WILL SHOW THE INSTRUCTOR DURING EACH OF THE PROJECT CHECKS.
1. 100 amp panel and overhead meter base
Branch Circuits:
• 2 receptacles using Romex
• A single pole switch and 2 lights using Romex
• A 240 range receptacle
• A hard wired, battery back-up smoke alarm.
(See instructor for the smoke test)
2. 200 amp service panel and overhead meter base
Branch Circuits:
• An electric heater with a single or double pole breaker
• A fused dis-connect with a junction box and a single phase AC motor.
• A low voltage door bell system for a front and back door chime.
3. A double overhead meter base with 2 -100 amp panels.
Branch Circuits:
• One panel will have a single pole switch to a light using EMT conduit. The conduit size can be your choice, but must have a 16” stub up to the light.
• The second panel will have 2 receptacles using EMT conduit. The receptacles must be 18” to center from the floor. A GFCI circuit breaker must be installed. A single pole switch to a florescent light using Romex.
4. 200 amp service panel and overhead meter base
Branch Circuits:
• 3 way switches controlling a light using Romex
• 1 receptacle using PVC conduit. The PVC conduit must be bent into a 90 degree bend using the PVC heater
• 1 receptacle 23” from the floor using EMT conduit
• A single pole switch controlling a light using EMT. The switch must be 54” to center and the light must be in the center of the stall overhead
5. 200 amp service panel with a service mast.
Branch Circuits:
• 2-3 way switches and 2-4 ways switches controlling 2 lights.
• A single pole switch operating a light and a split receptacle using wire mold
• A single pole switch at 54” to center and a light on center of stall ceiling using PVC. Use the PVC heater to make any bends
6. 200 amp service panel with a service mast.
Branch Circuits:
• 2-3 way switches and 1-4 ways switch controlling 2 lights. There will be 1 conduit per switch and light. All going to 1 junction box. All connections are to be made in the junction box.
• A door chime and button are to be installed
7. 200 amp underground meter base with expansion fitting and service panel
Branch Circuits:
• 3 way switches and a 4 way controlling 3 lights using Romex
• A single pole controlling a split receptacle using Romex
8. Install a 30 amp sub panel onto project #7 and install the following circuits
Branch Circuits:
• A single pole switch controlling 4 light fixtures
• A doorbell with 2 pushbuttons. 1 for the front door and 1 for the back door
9. Install a 100 amp overhead service and a 200 amp service side by side.
• To update from an old to a new service the power supply should be connected to the weather head of the 100 amp service.
• For a powered switch over, you must make sure the instructor is aware of the process.
• You must have a qualified watchman ready to assist you in the stall.
• You must be suited up in the arc flash suit.
• The instructor will guide you in the process.
• A DETAILED material list must be made of all materials and devices used.
• A minimum of 10 National Electrical Code articles are to be found that pertain to this project.
9a. To perform a non-powered switch over you must follow all steps listed in project #9. The instructor will guide you in the process; however power WILL NOT be on.
NAME: LEVEL: DATE:
CHECK LIST FOR THE SERVICES PACKET
|Task |Points |Points Earned|
| |Available | |
|The student chose the correct tools to install a 100 amp overhead service. |20 | |
|(-1 pt. for each incorrect answer) | | |
|The student installed the 100 amp overhead service according to N.E.C. and industry standards. |50 | |
|(-5 pts. for each NEC violation) | | |
|The student used the proper PPE to install the 100 amp overhead service. |50 | |
|(-5 pt. for each violation) | | |
|The student used the FLIR to check the 100 amp overhead service. |50 | |
|(Correct/Incorrect) | | |
|The student chose the correct tools to install a 100 amp underground service. |20 | |
|(-1 pt. for each incorrect answer) | | |
|The student installed the 100 amp underground service according to N.E.C. and industry standards. |50 | |
|(-5 pts. for each NEC violation) | | |
|The student used the proper PPE to install the 100 amp underground service. |50 | |
|(-5 pts. for each violation) | | |
|The student used the FLIR to check the 100 amp underground service. |50 | |
|(Correct/Incorrect) | | |
|The student chose the correct tools to install the sub-panel w/circuits onto an existing panel. |20 | |
|(-1 pt. for each incorrect answer) | | |
|The student installed the sub-panel w/circuits according to N.E.C. and industry standards. |50 | |
|(-5 pt. for each NEC violation) | | |
|The student used the proper PPE to install the sub-panel w/ circuits. |50 | |
|(-5 pts. For each violation) | | |
|The student used the FLIR to check the sub panel w/circuits. |50 | |
|(Correct/Incorrect) | | |
|The student installed the smoke alarm to industry standards. |10 | |
|(-2 pts. Per violation) | | |
|The smoke alarm passed the “smoke test” according to industry standards. |10 | |
|(+10 pts. Passed smoke test / -10 failed smoke test) | | |
|The student installed the low voltage doorbell circuit according to N.E.C. and industry standards. |20 | |
|(-5 pt. for each violation) | | |
|The student demonstrated the proper use of the thermal imaging camera for each project. |50 | |
|(-5 pt. for each violation) | | |
|Total Points Available/Earned |600 | |
INSTRUCTOR SIGNATURE: DATE:
Name: Date: Level:
VOCABULARY FOR SERVICE PANELS
|CC.1.3.11-12.I Determine or clarify the meaning of unknown and multiple-meaning words and phrases based on grade level reading and content, |
|choosing flexibly from a range of strategies and tool |
|CC.3.5.11-12.D. Determine the meaning of symbols, key terms, and other domain-specific words and phrases as they are used in a specific scientific |
|or technical context relevant to grades 11–12 texts and topics. |
1. Branch circuit:
2. Volt-ampere:
3. Service Disconnect:
4. Feeder:
5. General lighting circuit:
6. Dwelling unit:
7. Load side:
8. Bathroom branch circuit:
9. Small appliance branch circuit:
10. Weather head:
Name: Date: Level:
VOCABULARY FOR SUB-PANELS
CC.1.3.11-12.I Determine or clarify the meaning of unknown and multiple-meaning words and phrases based on grade level reading and content choosing flexibly from a range of strategies and tools.
1.1.11.F Understanding the meaning of and apply key vocabulary
1. Sub-Main:
2. Laterals:
3. Back Feeding:
4. M.L.O. PANEL:
5. Lug:
6. Service Mast:
7. Bonding Jumper:
8. Riser:
9. Transformer:
10. Supplemental Ground:
11. Service Drop:
|Name: Date: Level: |
| |
|VOCABULARY FOR UPDATING SERVICES |
|CC.1.3.11-12.I Determine or clarify the meaning of unknown and multiple-meaning words and phrases based on grade level reading and content, |
|choosing flexibly from a range of strategies and tool |
|CC.3.5.11-12.D. Determine the meaning of symbols, key terms, and other domain-specific words and phrases as they are used in a specific scientific |
|or technical context relevant to grades 11–12 texts and topics. |
1. O.S.H.A.:
2. Jumper:
3. Main:
4. Back Feed:
5. Load Center:
6. Distribution System:
7. Knockout:
8. N.E.M.A.:
9. Bus Bar:
10. Trim Assembly:
Name: Date: Level:
10 National Electric Code articles that pertain to the projects you have completed.
|Article # |Code Article Topic |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
Service Post-Test
Name: Date:
CC.3.5.11-12.B. Determine the central ideas or conclusions of a text; summarize complex concepts, processes, or information presented in a text by paraphrasing them in simpler but still accurate terms.
CC.3.6.11-12.E. Use technology, including the Internet, to produce, publish, and update individual or shared writing products in response to ongoing feedback, including new arguments or information.
3.1.12.B Apply concepts of models as a method predict and understand science and technology
True/False
Indicate whether the sentence or statement is true or false.
____ 1. Electrical Metallic Tubing is permitted to be used as service raceway.
____ 2. If a metal water pipe is used as a grounding electrode, a supplemental grounding electrode must be used if the resistance to ground exceeds 25 ohms.
____ 3. In a sub-panel, the grounding bar and the neutral bar are electrically connected with a screw.
____ 4. When connecting sub-panel feeder conductors in the main panel, both the grounded neutral conductor and the grounding conductor are connected to the main panel grounded neutral bar.
Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
____ 5. The conductors that run overhead from the utility transformer to the residence are called the __________.
|a. |service entrance cable |
|b. |service drop conductors |
|c. |service laterals |
|d. |SEU cable |
____ 6. __________ brings the electrical power from the point of attachment to the meter socket and then on to the main service equipment.
|a. |Triplex cable |
|b. |Service drop conductors |
|c. |Service laterals |
|d. |Service entrance cable |
____ 7. A(n) __________ is a plastic or fiber fitting designed to screw onto the ends of a conduit or cable connector to provide protection to the conductors.
|a. |threaded hub |
|b. |bushing |
|c. |connector nut |
|d. |insulated bushing |
____ 8. When installing an overhead service, _____________ feet of conductor should stick out from the weather head for the formation of a drip loop.
|a. |1 |
|b. |1.5 |
|c. |2 |
|d. |3 |
____ 9. When using service entrance cable for the run between the weather head and the meter socket, the cable must be supported within __________ of both the weather head and the meter socket.
|a. |12" |
|b. |18" |
|c. |24" |
|d. |30" |
____ 10. The service conductors that run underground from the utility transformer to the meter socket are known as __________.
|a. |service drop conductors |
|b. |service entrance conductors |
|c. |service laterals |
|d. |triplex conductors |
____ 11. Where underground service conductors exit the trench to run to the meter socket, __________ is not permitted to be used for protection from physical damage.
|a. |rigid metal conduit |
|b. |intermediate metal conduit |
|c. |electrical metal conduit |
|d. |schedule 80 rigid nonmetallic conduit |
____ 12. Where underground service cables exit the trench and run up a utility pole to the transformer, the conductors must be protected to a height of __________ feet above final grade.
|a. |3 |
|b. |8 |
|c. |10 |
|d. |12 |
____ 13. When installing an underground service, a warning tape must be installed at least __________ above the buried service entrance conductors.
|a. |8" |
|b. |12" |
|c. |18" |
|d. |24" |
____ 14. The NEC requirements for minimum burial depths are found in Table __________.
|a. |310.16 |
|b. |300.5 |
|c. |250.66 |
|d. |220.3 |
____ 15. The NEC provides the requirements for working clearances around electrical equipment in Article __________.
|a. |210 |
|b. |200 |
|c. |110 |
|d. |100 |
____ 16. According to the NEC, the working space in front of a service entrance panel must be 6.5' high, 30" wide, and extend at least __________ feet in front of the panel.
|a. |1 |
|b. |3 |
|c. |2 |
|d. |4 |
____ 17. The grounding electrode conductor is attached to the metal pipe no more than __________ feet from the point where the metal water pipe enters the house.
|a. |3 |
|b. |5 |
|c. |7 |
|d. |9 |
____ 18. The feeder cable supplying power to a sub-panel must be supported within __________ inches of each panel.
|a. |8 |
|b. |12 |
|c. |24 |
|d. |30 |
____ 19. A service mast is made of rigid metal conduit or intermediate metal conduit and should be at least a __________ trade size conduit to provide adequate strength.
|a. |1" |
|b. |1.5" |
|c. |2" |
|d. |2.5" |
Completion
Complete each sentence or statement.
20. ___________________ is a wiring technique that allows electrical power from an existing electrical panel to be fed to a new panel by a short length of cable.
21. Incoming electrical power is connected to the _______________ side of electrical equipment.
22. Outgoing electrical power is connected to the _______________ side of electrical equipment.
23. Conduit clamps used to support the service raceway must be installed within _______________ feet of the weatherhead and meter socket.
24. A(n) _______________ is a type of conduit body that allows for a 90 degree change of direction in a raceway path. It is often used to allow the service raceway to run from the meter socket, through the side of the house, and continue to the service equipment enclosure.
25. The meter socket is usually located so the center of the kWh meter is _______________ feet above final grade.
26. A __________________ is installed over the service cable at the point where it goes through the hole in the side of the house to prevent water from entering the house.
27. If Aluminum service conductors are being used, make sure a(n) _______________ is used to prevent oxidation of the conductors.
CC.3.6.11-12.H. Draw evidence from informational texts to support analysis, reflection, and research.
Residential & Industrial Electricity
K-W-L WORKSHEET
NAME: LEVEL: DATE:
ARTICLE TITLE:
TIME START: TIME FINISH:
| | |
|K What do I already KNOW | |
|about this topic? | |
| | |
|W What do I WANT to know | |
|about this topic? | |
| | |
|L What did I LEARN | |
|after reading ABOUT | |
|this topic? | |
I checked the following before reading:
➢ Headlines and Subheadings
➢ Italic, Bold, and Underlined words
➢ Pictures, Tables, and Graphs
➢ Questions or other key information
I made predictions AFTER previewing the article.
Comments:
• Instructor Signature:
Service Pre-Test
Name: Date:
CC.3.5.11-12.B. Determine the central ideas or conclusions of a text; summarize complex concepts, processes, or information presented in a text by paraphrasing them in simpler but still accurate terms.
CC.3.6.11-12.E. Use technology, including the Internet, to produce, publish, and update individual or shared writing products in response to ongoing feedback, including new arguments or information.
3.1.12.B Apply concepts of models as a method predict and understand science and technology
True/False
Indicate whether the sentence or statement is true or false.
____ 1. Electrical Metallic Tubing is permitted to be used as service raceway.
____ 2. If a metal water pipe is used as a grounding electrode, a supplemental grounding electrode must be used if the resistance to ground exceeds 25 ohms.
____ 3. In a sub-panel, the grounding bar and the neutral bar are electrically connected with a screw.
____ 4. When connecting sub-panel feeder conductors in the main panel, both the grounded neutral conductor and the grounding conductor are connected to the main panel grounded neutral bar.
Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
____ 5. The conductors that run overhead from the utility transformer to the residence are called the __________.
|a. |service entrance cable |
|b. |service drop conductors |
|c. |service laterals |
|d. |SEU cable |
____ 6. __________ brings the electrical power from the point of attachment to the meter socket and then on to the main service equipment.
|a. |Triplex cable |
|b. |Service drop conductors |
|c. |Service laterals |
|d. |Service entrance cable |
____ 7. A(n) __________ is a plastic or fiber fitting designed to screw onto the ends of a conduit or cable connector to provide protection to the conductors.
|a. |threaded hub |
|b. |bushing |
|c. |connector nut |
|d. |insulated bushing |
____ 8. When installing an overhead service, _____________ feet of conductor should stick out from the weather head for the formation of a drip loop.
|a. |1 |
|b. |1.5 |
|c. |2 |
|d. |3 |
____ 9. When using service entrance cable for the run between the weather head and the meter socket, the cable must be supported within __________ of both the weather head and the meter socket.
|a. |12" |
|b. |18" |
|c. |24" |
|d. |30" |
____ 10. The service conductors that run underground from the utility transformer to the meter socket are known as __________.
|a. |service drop conductors |
|b. |service entrance conductors |
|c. |service laterals |
|d. |triplex conductors |
____ 11. Where underground service conductors exit the trench to run to the meter socket, __________ is not permitted to be used for protection from physical damage.
|a. |rigid metal conduit |
|b. |intermediate metal conduit |
|c. |electrical metal conduit |
|d. |schedule 80 rigid nonmetallic conduit |
____ 12. Where underground service cables exit the trench and run up a utility pole to the transformer, the conductors must be protected to a height of __________ feet above final grade.
|a. |3 |
|b. |8 |
|c. |10 |
|d. |12 |
____ 13. When installing an underground service, a warning tape must be installed at least __________ above the buried service entrance conductors.
|a. |8" |
|b. |12" |
|c. |18" |
|d. |24" |
____ 14. The NEC requirements for minimum burial depths are found in Table __________.
|a. |310.16 |
|b. |300.5 |
|c. |250.66 |
|d. |220.3 |
____ 15. The NEC provides the requirements for working clearances around electrical equipment in Article __________.
|a. |210 |
|b. |200 |
|c. |110 |
|d. |100 |
____ 16. According to the NEC, the working space in front of a service entrance panel must be 6.5' high, 30" wide, and extend at least __________ feet in front of the panel.
|a. |1 |
|b. |3 |
|c. |2 |
|d. |4 |
____ 17. The grounding electrode conductor is attached to the metal pipe no more than __________ feet from the point where the metal water pipe enters the house.
|a. |3 |
|b. |5 |
|c. |7 |
|d. |9 |
____ 18. The feeder cable supplying power to a sub-panel must be supported within __________ inches of each panel.
|a. |8 |
|b. |12 |
|c. |24 |
|d. |30 |
____ 19. A service mast is made of rigid metal conduit or intermediate metal conduit and should be at least a __________ trade size conduit to provide adequate strength.
|a. |1" |
|b. |1.5" |
|c. |2" |
|d. |2.5" |
Completion
Complete each sentence or statement.
20. ___________________ is a wiring technique that allows electrical power from an existing electrical panel to be fed to a new panel by a short length of cable.
21. Incoming electrical power is connected to the _______________ side of electrical equipment.
22. Outgoing electrical power is connected to the _______________ side of electrical equipment.
23. Conduit clamps used to support the service raceway must be installed within _______________ feet of the weather head and meter socket.
24. A(n) _______________ is a type of conduit body that allows for a 90 degree change of direction in a raceway path. It is often used to allow the service raceway to run from the meter socket, through the side of the house, and continue to the service equipment enclosure.
25. The meter socket is usually located so the center of the kWh meter is _______________ feet above final grade.
26. A __________________ is installed over the service cable at the point where it goes through the hole in the side of the house to prevent water from entering the house.
27. If Aluminum service conductors are being used, make sure a(n) _______________ is used to prevent oxidation of the conductors.
-----------------------
[pic]
Electrical & Power Transmission Installers
CIP 46.0399
Name:
Date:
Learning Guide Due Date:
Pre Test Due Date:
Post Test Due Date:
Schuylkill Technology Center-
South Campus
15 Maple Avenue
Marlin, Pennsylvania 17951
(570) 544-4748
Total Hours-26
Level(s)-2
Total Hours-60
Level(s)-2
*CORE CURRICULUM STANDARDS*
*ACADEMIC STANDARDS*
Drip Loops (36” minimum)
Riser w/stand –off bracket
(2) 8’x 5/8” Ground rods. 6’ apart and 8’ done, or on a 45 degree angle or buried horizontal 24”
Conduit buried minimum 24” with warning tape 18” above conduit
Service Conductors must be protected 8’ up from grade level. (Minimum)
Service Laterals
MUST BE 25 OHMS OR LESS!!
If mast is 24” or higher, there is a possibility of needing a guy wire to support mast…CONSULT THE AUTHORITY HAVING JURSIDICTION (A.H.J.)
[pic]
Water Pipe Clamps
Acorn Clamps for Ground Rod
Correct/Out of 600
Grade Percentage
Check One Percentage Task Grade
← Below Basic 0%-69% 0-6
← Basic 70%-85% 7
← Competent 86%-92% 8-9
← Advanced 93%-100% 10
................
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