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Download NLC FINALS - EG2 - TERM 2103 LATEST QUESTIONS AND VERIFIED ANSWERS and more Exams Electrical Engineering in PDF only on Docsity!
What are the three key elements needed for a basic electrical circuit to function properly? - Correct Answer 1. Electrical pressure or voltage 2. A conductor (something to transmit the energy) 3. Aload (something to use the electrical energy) pg 10 What is an open circuit? - Correct Answer The inability of electrons to flow through a conductor and provide power because the conductor does not provide a complete path. pg 10 What is a short circuit? - Correct Answer A circuit that does not have a load, or in which the load has been bypassed. pg 12 What is a fuse? - Correct Answer An intentionally weakened point in a circuit that bursts open when current flow is excessive. pg 12 Does a short circuit have very high or very low resistance? Does it have high or low amperage? - Correct Answer Very low resistance, very high amperage pg 12 How many paths can current in a series circuit flow? - Correct Answer One path. pg 13 In a series circuit, because there is only one path for current flow, the current is the at any point in the circuit? - Correct Answer Same pg 13 What is the example of a series circuit noted in the book (page 13)? - Correct Answer Christmas tree lights (street lights are also an example on page 14) How many paths can current travel in a parallel circuit? - Correct Answer Multiple paths. pg 14 All power lines are what type of circuit type? - Correct Answer Combination circuit type (A mix of series and parallel) pg 14 pg 19 Be able to calculate voltage, amperage and watts using E =| X R formula. - Correct Answer Pg 17-20 for examples Why are power lines considered combination type circuits? - Correct Answer Because the equipment connected to it is generally in series with the line; however, the layout of the circuit is predominately parallel. pg 21 The voltage in a parallel circuit is , while the current different points in the circuit. - Correct Answer the same changes pg 23 On a parallel circuit, the total current supplied by the source is the of the current demands of the individual loads. - Correct Answer addition pg 23 Be able to solve for current and amperage on a parallel circuit. - Correct Answer Pg 24-26 for examples. at How many currents are used to supply the power and energy in a three phase system? - Correct Answer 3 currents pg 28 What are the 3 advantages of three-phase systems over single-phase systems? Which of the 3 did we note as most important for the test? - Correct Answer 1. A 73% increase in power capability for a 50% increase in conductors 2. Less pulsating force applied to rotating generators and motors 3. Generators, transformers, and motors are smaller and less expensive than single-phase equipment of the same rating. #3 was most important for the test. pg 28 The 3 coils of a three-phase generator are spaced how many degrees apart? - Correct Answer 120 degrees pg 120 Throw back to EG1. How do you calculate RMS? How do you calculate Peak? - Correct Answer RMS = 0.707 * Peak Peak = 1.414 * RMS How do you calculate Coil Current and Phase Current in a Delta System? Which one is always higher? - Correct Answer Coil Current = Phase current / eg? Phase Current = Coil Current x 1.732 Phase current is always higher. pg 33 Could a lineman "safely" work on one energized wire from the pole, bare handed, without risking electrocution? Yes or no? - Correct Answer Yes. pg 34 Four wire Wye systems can experience more electrical interruptions because the is in close proximity to the phases - Correct Answer Neutral pg 35 What is the most widely used wire system? - Correct Answer A four-wire WYE system pg 36 How many phases are required for a "single-phase" tap line? - Correct Answer Two phases. pg 36 A four-wire WYE system is much more reliable in regards to , because the neutral is extended throughout the circuit and faults have an immediate and reliable path to the source. - Correct Answer Fault protection. pg 36 If a phase in a three-wire WYE system fell to the ground, how would the current return to the source so the protective equipment could trigger? - Correct Answer Through the earth. pg 36 All generators connected to a regional transmission network must all do what at any given time to ensure that they parallel and function properly? - Correct Answer Rotate at the exact same angle of rotation pg 37 Be able to identify incorrect phasing on a picture. Flip card for Page - Correct Answer Page 39-42 If the phase sequence is unchanged, rotation will - Correct Answer Remain unchanged. pg 39 Rotor rotates. Understand the structure of these motors, on page 47. pg 47 Each phase is wrapped around 2 stator poles, degrees apart, which causes them to develop ? - Correct Answer 180 degrees Opposite magnetic polarities pg 48 What does the term "peak load" refer to? - Correct Answer The time of day when the demand for electricity is highest. Typically late afternoon and early evening hours. pg 54 What is the definition of "smart grid" as defined by the Department of Energy? - Correct Answer Incorporation of the concepts, philosophies, and technologies that enable the INTERNET into the electrical grid. pg 54 What does SCADA stand for? - Correct Answer Supervisory Control and Data Acquisition What is "cascading" and when is it most likely to occur? - Correct Answer It is a condition in which an outage on a circuit causes outages on interconnected circuits. This happens when those circuits can't handle the additional load and is most likely to occur during peak loading times. pg 57 What best explains why we need a smarter electrical grid? - Correct Answer The strain on the grid during peak loading and the effects of cascading power failures. pg 59 Out of the 10 concepts and philosophies discussed on page 60, that drive the movement towards smarter electrical grids, which 4 were discussed most and labeled as most important for the test? - Correct Answer 1. Renewable (the grid can accept power from renewable resources to reduce dependency on pollutant emitting generators) 2. Automation (sense and react to situations without human help) 3. Self-healing (The goal is to keep more customers in service) 4. Demand Side Management (can reduce consumption of electricity by customers, especially during peak loading) pg 60 What is bi-directional energy flow and when is it necessary to configure a system to allow it? - Correct Answer This is where power can flow through the What is Compressed Air Energy Storage? - Correct Answer When compressed air is forced into the cavity or storage area by large volume compressors and released through a turbine when needed. pg 66 pg 66 What is Flywheel technology? - Correct Answer Produces electricity by rotating a rotor at a very high speed, and then using the rotating energy to produce electricity pg 67 What is ACCC conductor? How much current can it carry when compared to its predecessors of the same size? - Correct Answer Aluminum Conductor Composite Core. It can carry TWICE as much current. pg 68 1. What unit, also called syncrophasors, are strategically located in substations and check phase angle on voltage and current waves? 2. How many times does it do this per second? 3. If it notices an issue, what key substation equipment does it automatically trigger? - Correct Answer 1. Phasor Measurement Units 2. 30 times per second 3. Capacitors and reactors pg 69 What system allows phasor measurement units to operate in unison? - Correct Answer Wide Area Management system pg 69 What is Dynamic Line Loading? What is one major advantage of it? - Correct Answer The philosophy that allows real time conditions of conductors to be monitored. Measuring conductor temperature, also known as line thermal monitoring, using infrared imaging. pg 70 What is Optical Ground Wire (OPGW) and what is its purpose? - Correct Answer OPGW is shield wire installed at the top of structures. The inner optic fibers can be used for high-speed communication and the outer wire is used to protect from lightning. pg 71 What are micro grids? - Correct Answer When larger portions of circuits begin Islanding. pg 72 What are two objectives that need to be met by bi-directional energy flow switching equipment? - Correct Answer 1. Provide means to isolate and sectionalize as designed Be able to identify the functional differences between a Legacy Capacitor and a Smart Capacitor, as well as in a picture. Page 80-81 - Correct Answer One way to ID smart vs legacy is there will be 4 cutouts on a smart capacitor. 1 to each capacitor and 1 to a transformer. On these, the cutouts are meant to protect the main line. pg 80-81 Be able to identify the functional differences between a Legacy regulator and a Smart Regulator, as well as in a picture (Page 82-83) - Correct Answer One way to identify in a picture is a smart regulator will only have one control box that can operate multiple regulators, whereas legacy needs one control box per regulator. pg 82-83 What is "conservation voltage reduction? - Correct Answer Intentional lowering of system voltage to help reduce demand on the system pg 82 What indicator and sensors can be quickly installed on a conductor to provide data for troubleshooting and localized power quality disturbances? - Correct Answer Fault Indicators and sensors pg 84 What does a smart home allow the homeowner the ability to do? - Correct Answer It allows them to play a more active role in their energy consumption. pg 85 What do smart homes make customers more aware of? - Correct Answer Their energy usage and the times of day that will be the most cost-effective to use electricity. pg 86 What is special about the power line carriers communication technique and protocol? - Correct Answer It is very proprietary and difficult to decode even if a person has the right equipment. pg 87 What does a Home-Area-Network (HAN) with smart meters allow to be relayed to a smart home/appliances? - Correct Answer It will relay any price changes to the home-area-display unit which will then communicate with the smart appliances. Giving the customer an alert of the change is important. pg 88 What do some companies offer to customers in a home-area-network (HAN) without smart meters so they can see individual appliances’ energy consumption? - Correct Answer Smart Plugs What is a plug-in hybrid vehicle? What type of outlet can they be charged on? - Correct Answer A vehicle that runs on battery power until the charge is too low, then it switches to a combustion engine. They can be charged by plugging into a standard 120-volt outlet. pg 93 What is range anxiety? - Correct Answer A drivers fear of being stranded by a depleted battery before reaching their destination pg 93 
