Lesson 3 Medium (and High) Voltage and Insulation Test Instruments
Lesson 3: Medium (and High) Voltage and Insulation Test Instruments
Study online at https://quizlet.com/_jv3rlj
1. Typically any voltage above 50 VAC is considered an True
electrical shock hazard.
2. When energized parts of an electrical circuit are ex- distance
posed, such as where conductors are terminated at
fuse or circuit breaker panels, ? is used as the insulator.
3. Why must cable heights be re-measured occasionally? All of the above
4. Cable height meters work by using radio frequency False
waves and do not have to come in contact with any
cable.
5. It is important to check a high voltage detector on a piezo
known (energized) voltage source or ? verifier before
taking a measurement on an unknown voltage source.
6. A noncontact voltage detector is a test instrument that True
indicates the presence of voltage without displaying
the actual amount of voltage present.
7. A(n) ? high voltage meter is a voltmeter specifically de- contact
signed to take measurements on high voltage cables.
8. High voltage test probes should not be used to take all of the above
measurements in high current applications such as ? .
9. A high voltage ammeter is a test instrument specif- False
ically designed to identify the three phases of a
three-phase distribution system as L1, L2, and L3.
10. Noncontact high voltage ? are designed to be used as ammeters
current clamps but have open ends (a U shape) to allow
safer current measurements.
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, Lesson 3 Medium (and High) Voltage and Insulation Test Instruments
Lesson 3: Medium (and High) Voltage and Insulation Test Instruments
Study online at https://quizlet.com/_jv3rlj
11. Insulation has the lowest resistance when first placed False
into service on conductors and electrical devices.
12. What two basic measurements are taken to test insu- I. and III.
lation resistance?
I. The actual leakage current flowing through the insu-
lation.
II. The actual leakage current flowing through the con-
ductor.
III. The actual resistance of the insulation.
IV. The actual resistance of the conductor.
13. Using the general rule of thumb, leakage current 1
through insulation must not be greater than ? mA for
each 1000 V of operating voltage.
14. ? is a term used to describe an electrical product de- Double-insulated
signed so that a single ground fault cannot cause a
dangerous electrical shock through any exposed parts
of the products that can be touched by an electrician.
15. When leakage current exceeds the specified limit, a(n) three-prong
? power cord must be used.
16. On a ? , any leakage current flows through the ground three-prong power cord
(green) conductor back to ground during normal op- device
eration. The ground conductor prevents the exposed
metal parts of the electrical device from becoming en-
ergized to the point of causing an electrical shock.
17. Design
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Lesson 3: Medium (and High) Voltage and Insulation Test Instruments
Study online at https://quizlet.com/_jv3rlj
1. Typically any voltage above 50 VAC is considered an True
electrical shock hazard.
2. When energized parts of an electrical circuit are ex- distance
posed, such as where conductors are terminated at
fuse or circuit breaker panels, ? is used as the insulator.
3. Why must cable heights be re-measured occasionally? All of the above
4. Cable height meters work by using radio frequency False
waves and do not have to come in contact with any
cable.
5. It is important to check a high voltage detector on a piezo
known (energized) voltage source or ? verifier before
taking a measurement on an unknown voltage source.
6. A noncontact voltage detector is a test instrument that True
indicates the presence of voltage without displaying
the actual amount of voltage present.
7. A(n) ? high voltage meter is a voltmeter specifically de- contact
signed to take measurements on high voltage cables.
8. High voltage test probes should not be used to take all of the above
measurements in high current applications such as ? .
9. A high voltage ammeter is a test instrument specif- False
ically designed to identify the three phases of a
three-phase distribution system as L1, L2, and L3.
10. Noncontact high voltage ? are designed to be used as ammeters
current clamps but have open ends (a U shape) to allow
safer current measurements.
1/5
1
, Lesson 3 Medium (and High) Voltage and Insulation Test Instruments
Lesson 3: Medium (and High) Voltage and Insulation Test Instruments
Study online at https://quizlet.com/_jv3rlj
11. Insulation has the lowest resistance when first placed False
into service on conductors and electrical devices.
12. What two basic measurements are taken to test insu- I. and III.
lation resistance?
I. The actual leakage current flowing through the insu-
lation.
II. The actual leakage current flowing through the con-
ductor.
III. The actual resistance of the insulation.
IV. The actual resistance of the conductor.
13. Using the general rule of thumb, leakage current 1
through insulation must not be greater than ? mA for
each 1000 V of operating voltage.
14. ? is a term used to describe an electrical product de- Double-insulated
signed so that a single ground fault cannot cause a
dangerous electrical shock through any exposed parts
of the products that can be touched by an electrician.
15. When leakage current exceeds the specified limit, a(n) three-prong
? power cord must be used.
16. On a ? , any leakage current flows through the ground three-prong power cord
(green) conductor back to ground during normal op- device
eration. The ground conductor prevents the exposed
metal parts of the electrical device from becoming en-
ergized to the point of causing an electrical shock.
17. Design
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