1. What is the purpose of the arrestor shunts on the dual voltage mobile sub?
    To allow 110 KV or 50 KV high line voltages to be used with those arrestor stacks, by connecting ground cable to the center of the stack, using one arrestor for the lower voltage and connected at the bottom of the stack, using both arrestors for the higher voltage.
  2. What is the operating pressure of Mobile #4 SF 6 high side breaker?
    Minimum operating pressure is 64 PSI.

    • (Transportation pressure is 10 PSI max.)
  3. Never ______ - _________ the secondary terminals of a voltage transformer,
    otherwise it will cause the unit to _____________________________________

    short - circuit

    • overheat and fail in a short period of time.
  4. To short and ground a CT with a shorting block, ___ screws are used.
    With X1 marked as polarity, when the burden is connected to X4 and X5, ____ is now polarity.
    The lowest lead number will be the ________ lead.
    3 screws

    X 4

  5. Three basic CT configurations:
    • Ring Core CT
    • Split Core CT

    Wound Primary CT
  6. When a CT's secondary voltage rise above the "knee" no longer accurate due to _________ ___________. Where single ratio CT's are used on a feeder breaker CT's rating should match _____ ______ amps of the breaker.
    Magnetic Saturation.

    Full Load
  7. What electrical test must be conducted on Mobile subs prior to energizing?


  8. Many CT's are provided with a short circuiting device, and should be shorted until a suitable _________ is connected, such as an _________, _________, _______________________, etc.

    Ammeter, Wattmeter, Watt hour meter relay
  9. On a MRCT only one _______ can be used at a time.
Card Set
Step6 Quiz3 Tech