08-HW_08_Soln

Expansion fittings and telescoping sections of metal raceways shall be made electrically continuous by _____ or other means. Select one: A. GROUNDING ELECTRODE B. GROUNDED CURRENT CARRYING CONDUCTOR C. EQUIPMENT BONDING JUMPER

Equipment Grounding  13. A metal elbow is a part of a nonmetallic, underground raceway. The elbow won't need to be grounded as long as it's encased in at least _______ inches of concrete. A. 4 B. 5 C. 2 D. 6   13 A. Which of the following can be in the form of a wire and is required to be installed with feeders and branch circuits? A. Phased neutral conductorB. Equipment grounding conductor C. Grounded neutral conductorD. Grounding electrode conductor

Q1. Why Earth Leakage Circuit Breaker is important? Draw a neat diagram of Earthing system.

A feeder installation consists of 208Y/120-volt, 3-phase, 4-wire electrical system with a balanced load of fluorescent lighting. Each phase conductor has a 340 ampere load. The MINIMUM permitted ampacity of the neutral conductor for this feeder is ________.   238 amperes   275 amperes   340 amperes   680 amperes.

10.a. Which of the following is a condition of the exception that allows the grounded conductor of feeders tobe used for grounding at separate buildings or structures?A. There are common electrically continuous metallic paths between the feeder source and the destination at the structure served.B. There are common electrically continuous nonmetallic paths between the equipment grounding conductor and the destinationat the structure served.C. An equipment grounding conductor isn't included with the supply circuit to the separate structure.D. Ground-fault protection of equipment is provided on the supply side of the feeder.10.b. A service disconnection means must be installed adjacent to, within sight of, and no more than_______ feet from a mobile home.A. 20B. 30C. 10D. 50

q1/ choose the correct answer Using bundled conductors, corona effect will  ______________ 1- increase 2- not change 3- decrease 4- become zero

(c) Draw a circuit diagram to represent a TN-C-S earthing system and briefly explain its advantages and disadvantages.   (d) Briefly explain how to estimate the height of air termination of a lightning protection system network using the rolling sphere method and protection angle method. (e) Briefly explain what is meant by Ground Potential Rise (GPR) and explain why an animal like cow would not be adequately protected against GPR.   Note : answer all or else dnt attempt the question

QUESTION 97 Where isolated metal water piping systems are installed in a multiple-occupancy building, the water pipes can be bonded with bonding jumpers sized in accordance with Table 250.122, based on the size of the _____.   a. rating of the largest overcurrent device supplying the occupancy   b. feeder conductors   c. service-entrance conductors   d. rating of the service equipment overcurrent device

A plug and connector used for cable termination is identified as 6P6C. The "6C" indicates that the connector has 6 contacts available.  has 6 contacts installed. is the sixth connector.  is for modems. Most of the loads supplied by an equipment branch are _______ V, three-phase. 480
  120 
 360            240 A/An _______ is a type of hazardous location protective equipment that allows non-explosionproof motors to be used in Class I locations by supplying a continuous flow of clean air to remove flammable vapors. gas detection system
  explosionproof apparatus
 dust-ignition-proof apparatus
  purged and pressurized apparatus If you're installing a generator that's rated to provide 100 A of current, the conductors you use must have a minimum capacity of 142 A.  135 A.  115 A.     150 A.

The minimum size raceway for the following branch circuit conductors is: Twelve, 6 AWG conductors with THHN insulation  Nine, 8 AWG conductors with THHN insulation  Eighteen, 10 AWG conductor with THHN insulation  One, 10 AWG equipment grounding conductor with THHN insulation

Refer to the National Electrical Code or the working drawings when necessary. Whereapplicable, responses should be written in complete sentences.A 300-kilovolt-ampere transformer bank consisting of three 100-kilovolt-amperetransformers has a 3-phase, 480-volt delta primary and a 120/240-volt, 3-phase, 4-wiredelta-connected secondary.For problems 1 through 4 show calculations and/or source of information. 1. What is the proper rating of the fuses to install for overcurrent protection of thesecondary?2. What is the kilovolt-ampere of the bank if one of the transformers is removed?

Refer to the National Electrical Code or the working drawings when necessary. Whereapplicable, responses should be written in complete sentences.A 300-kilovolt-ampere transformer bank consisting of three 100-kilovolt-amperetransformers has a 3-phase, 480-volt delta primary and a 120/240-volt, 3-phase, 4-wiredelta-connected secondary.For problems 1 through 4 show calculations and/or source of information 1. What is the full-load current in the primary? 2. What is the full-load current in the secondary?

Question R  give definition of the following: a. Conventional system b. Fixed-radix positional system c. Mix-radix positional system  Full explain this question and text typing work only       We should answer our question within 2 hours takes more time then we will reduce Rating Dont ignore this line.

Equipment Grounding    10. Which of the following statements about ground faults is true?A. They usually occur between any grounded circuit conductor and the equipment grounding conductor. B. They're often normal and typically intentional.C. They can't result from human error.D. They can happen if a conductive tool is dropped in an energized equipment's electrical enclosure.

When a service is supplies by a grounded system, the ________ is required to be routed from the utility supply system or source to the service disconnecting means enclosure and bonded to the service disconnecting means enclosure. a)Equipment bonding jumper b) Grounded conductor c) Grounding electrode d) Equipment grounding conductor

The arrangement of grounding connections shall ensure that the disconnection or the removal of a luminaire, receptacle, or other device fed from the box does not interrupt the electrical continuity of the ____________ providing an effective ground-fault current path. grounding conductor(s) ungrounded conductor(s) equipment grounding conductor(s) all of these.

L1. Boxes are classified by type, construction, andA. installation location.B. luminaire support capability.C. number of knockouts.D. power rating L2. Which of the following devices must be placed at each end of an armored cable to prevent damage tothe conductors?A. An insulating sliderB. An insertion couplingC. An antishort bushingD. A metal loop fitting L3. Which of the following is the maximum cross-sectional conductor fill area for underfloor raceways?A. 50%B. 60%C. 40%D. 30%

Explain each option & Choose the correct option. 4) The _ calculated load is rarely placed on an electrical system.A. optionalB. standardC. total 5) What's the primary disadvantage of using copper conductors?A. CostB. AvailabilityC. Weight 6) You're evaluating the components of a multioccupancy building that won't have an on-site employee. To be compliant with the NEC, each occupant will need to have access to their ownA. service-disconnecting means.B. service conductor.C. cable attachment point.D. emergency fire water pump disconnect ..

Connections from headers to cabinets and other enclosures, in cellular concrete floor raceways, shall be made by means of ______. Select one: A. LISTED METAL RACEWAYS. B. LISTED NONMETALLIC RACEWAYS. C. LISTED FITTINGS. D. A ONLY E. A AND B ONLY F. A, B, AND C

11.a. You're installing an isolated power system in a hospital that'll serve a group of patient care areas. Whichof the following colors must be used for the wire that connects to the terminal at each receptacle that'susually reserved for the neutral conductor?A. Green with a white stripeB. Orange with a distinct stripeC. White with an orange stripeD. Red with a black stripe 11.b. The _______ is typically where the service main bonding jumper is installed or where the systembonding jumper is installed for a separately derived system.A. equipotential planeB. site-isolating deviceC. point of groundingD. isolated power system