Electrical Systems week one

  1. what percent of today's systems are loop fed?
  2. what are the 5 main elements of the electrical system?
    • generation
    • transmission
    • sub transmission
    • distribution
    • substations
  3. generation voltage range
    13.8KV to 24KV
  4. Transmission voltage range
    230KV to 765KV
  5. sub transmission voltage range
    44KV to 138KV
  6. distribution substation voltage range
    2.4KV to 34.5KV
  7. what is the function of transmission lines?
    allow power to be transmitted over long distances to switch yards and sub transmission substations
  8. what is loss of power in transmission lines called
    line loss
  9. where do transmission lines begin and end?
    generation, where the power will be used
  10. 4 common transmission voltages
    230KV, 345KV, 500KV, 765KV
  11. Transmission lines deliver _____ blocks of power?
  12. blocks of power refer to?
    buying power
  13. are blocks of power set or undetermined?
  14. what lines deliver power directly to the customer?
    distribution lines
  15. sub transmission lines deliver ______ blocks of power
  16. what is the grid?
    generation facilities and other trans lines connecting to form a network through North America and Canada.
  17. what is the mission of the NERC?
    to promote the reliability of electric supply system in North America and Canada
  18. When do customer rates go up?
    when companies buy power from other counsels.
  19. what are the 3 pieces of equipment all substation have?
    • transformers
    • circuit breakers
    • circuit bus to redirect power if needed
  20. 4 common sub transmission voltages
    44KV, 69KV, 115KV, 138KV
  21. distribution substations ______ voltage
  22. where does distribution substations deliver power?
    customer transformers
  23. what voltages do customer transformers lower to?
    120v/240v, 120v/208v
  24. distribution voltage ranges
    2KV, to 34.5KV
  25. substation distribution lines deliver power directly to?
    commercial customer substation. which is the last place in the system where a voltage change can occur
  26. where are substation distribution lines supplied from?
    sub transmission lines
  27. substation distribution lines may be installed where?
    overhead or underground
  28. distribution lines are the ______, customers are the ____.
    source, load
  29. what is the main advantage AC has over DC?
    AC can be transformed, DC cannot
  30. what is the standard for hertz in the US?
    60 hertz
  31. where is DC most common?
  32. AC flow of electrical energy changes direction at a ______ ____.
    certain rate
  33. DC flow of electrical energy stays at the ____ ____.
    same rate
  34. what's the 3 primary functions substations preform?
    • change voltage of circuits from on level to another
    • connect and disconnect lines of equipment from other
    • control the flow of power by adjusting the voltage and current
  35. alternating current
    is the power that is produced by rotating a magnetic field near a conductor, as in a generator
  36. Amp
    • is the unit of measure for the flow
    • of electrons, or
    • current
  37. circuit
    • is a compilation of conductors and electrical
    • components that allow current to pass from a source to a load.
  38. conductor
    is any material that allows current to flow with essentially no resistance.
  39. Demarcation Point
    • A pin-pointed location in the electrical
    • system in which there is a change in ownership.
  40. Fault Current
    is an excessive current flow in a circuit caused be damage
  41. Hertz
    is the unit of measure for frequency.
  42. Insulator
    • is a non-conductive material that is used to isolate electrical energy from
    • ground.
  43. Kilovolt
    is the unit of measure for 1,000 volts
  44. Kilovolt-Ampere
    is the unit of measure for the amount of power that can be delivered to a load.
  45. Load
    • is the term used to describe the point at
    • which the power is consumed
  46. Mutual Induction
    • is the term used to describe the ability of one coil of conductor to induce
    • voltage into another coil.
  47. Neutral
    • is a conductor (typically for distribution)
    • that provides a ground reference for the load
  48. Ohm
    • is the unit of measure for the amount of
    • resistance in an electrical circuit.
  49. Parallel
    a circuit that provides more than one path for current to flow
  50. Potential
    is a term that refers to voltage
  51. Phase
    is a conductor that supplies power to the load,
  52. Series
    one path for current flow
  53. source
    point at which power is produced
  54. transformation
    • is the point in an electrical system in which
    • voltage changes from one level to another
  55. volt
    is the unit of measure for electrical pressure, or electromotive force
  56. watt
    is the unit of measure for electrical power
  57. NERC
    North American Electric Reliability Council
  58. common distribution operation voltages are
    7.2KV/12.47KV, 7.62KV/13.2KV, 12KV/20.8KV, 14.4KV/24.5KV, 19.9KV/34.5KV
  59. what distribution voltages are slowly being cut over to higher voltage
  60. common service voltages
    120v/240v, 120v/208v, 240v/480v, 277v/480v
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Electrical Systems week one
ES week one test