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FREE AND STUDY GAMES ABOUT CODOLOGY 5 EXAM
QUESTIONS
Actual Qs and Ans Expert-Verified Explanation
This Exam contains:
-Guarantee passing score -17 Questions and Answers -format set of multiple-choice -Expert-Verified Explanation Question 1: The electrical resistance of the fuse link is so low, it simply acts as a(n) ?during the normal circuit operation.
Answer:
conductor Question 2: A fuse listed to UL 2579 with a photovoltaic DC voltage rating is suitable for PV source and output circuit applications at its DC voltage rating or less, but may not be suitable for general industry DC applications.
Answer:
True Question 3: Cartridge fuses in circuits of any voltage where accessible to other than qualified persons and all fuses in circuits over 150 volts to ground shall be provided with a disconnecting means on their supply side. There are exceptions.
Answer:
True Article 240.40
Question 4: Low voltage fuses (600 volts or less) permitted to be used to protect service, feeder, and branch circuits are called branch-circuit overcurrent protective devices or branch-circuit fuses and are covered by the ? Standard.
Answer:
UL 248
Question 5: There are fuses that provide visual open fuse indication. The majority of fuses sold commercially are fuses which do not provide any visual indication.
Answer:
true
Question 6: Nontime-delay fuses use a(n) ? element fuse construction.
Select one:
- dissimilar metal
- dual
- single
- suppression
Answer:
Single Question 7: Which is not a performance requirement for a Class J, time-delay fuse (UL 248 Class J)?
- Have a voltage rating of 600 volts (AC)
- Have an interrupting rating of 200 kA (AC) or more
- Hold 500% inrush current for 10 seconds
- Must be resettabl
Answer:
Must be resettable after fault interruption (this is not a requirement)
Question 8: Generally, the overload element of a branch-circuit dual-element time-delay fuse will hold an overload that is five times greater than the ampere rating of the fuse for a minimum time of ? .
Answer:
10 seconds Question 9: A fuse uses a conductive ? link or links encapsulated in a tube with compacted silica sand and connected to contact terminals.
- break out
- filament
- fusible
- malleable
Answer:
- fusible
- They are resettable
Question 10: Which of the following can be the benefits of current-limiting fuse applications?
II. They have high interrupting ratings, which prevent misapplication in high fault current applications III. They provide consistent, reliable ove
Answer:
- II., III., and IV. Correct
- current-limiting
- rejection
- resistance
- voltage s
Question 11: Listed current-limiting fuses have ? features that help prevent the installation of fuses that cannot provide a comparable minimum protection level of critical ratings and performance.
Answer:
- rejection
Question 12: Supplementary fuses used to protect individual luminaires, appliances, or control circuits are allowed to be considered as the final branch-circuit overcurrent protective device.
Answer:
False
The correct answer is: 240.10
Question 13: Semiconductor fuses intended for the protection of electronic devices can be used to provide motor branch-circuit short-circuit and ground-fault protection for motor branch-circuits with power electronic drives that provide circuit overload protection
Answer:
True
The correct answer is: 430.52(C)(5)
Question 14: Photovoltaic applications present unique protection requirements resulting in the development of fuses with specific features for PV source circuits and output circuits application. Fuses listed to ? standard are required for these PV applications.S
Answer:
- UL 2579 Correct
Question 15: Dual-element time-delay fuses consist of two distinctive and separate types of elements that are connected in parallel inside the fuse. One is an overload element and the other is a short-circuit element.
Answer:
False Question 16: Compare a 100-ampere Class RK1, a 100-ampere Class J, and a 100-ampere Class CF fuse, all 600-volt, dual-element, time-delay with 300 kiloamperes ratings. With few exceptions, all can be applied the same way, have similar characteristics, and are of the s
Answer:
False Correct Question 17: Nontime-delay Class J fuses have slow response times and are best applied for equipment with high inrush currents or temporary overloads or surge currents.
Answer:
False