NCCER 26401 LOAD CALCULATIONS - FEEDERS AND SERVICES

NCCER 26401 LOAD CALCULATIONS -
FEEDERS AND SERVICES | QUESTIONS
AND ANSWERS|UPDATED VERSION
What is the adjusted ampacity for each of six No. 4/0 THHN copper current-carrying
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conductors in a single conduit? (Given: the ampacity of 4/0 THHN is 260A.) - 208A
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A farm has three buildings with loads of 82A, 65A and 15A. What is the total load?
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(Assume that there are no dwellings or motors.) - 117A
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If a store lighting load is 14,000VA (continuous), which of the following MUST be used for
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the circuit calculation? - 17,500VA
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Use of the 100' tap rule is limited to installation in high-bay manufacturing buildings with
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wall heights over _____. - 35'
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What is the demand factor allowed by the NEC® for calculating the neutral conductor
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size for an electric range load? - 70%
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Electric welders are covered in _____. - NEC Article 630
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Refer to the figure provided. What is the total load a feeder serving four 2hp motors, three
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5hp motors, one 15hp motor, and one 25hp motor? (All motors are 208V.) -
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219.8A
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Using the VA/linear foot method, the total VA that must be used in a service calculation
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for a 50' show window is _____. - 12,500VA
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The rules governing the design of circuits supplying power to boats is covered in _____.
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- NEC Article 555
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When the overcurrent protection for a conductor is located on the load end rather than the
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supply side of a conductor it is considered to be a(n) _____. - tap conductor
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When making service calculations for multi-family dwellings, additional demand factors
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may be applied to the portion of the neutral load greater than _____. - 200A
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When calculating the service requirement for a particular building, the first step is to
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_____. - determine the floor area of the building
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NEC Table 220.12 requires a minimum general lighting load for office buildings to be
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based on _____. - 1.3 VA/ft2
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The minimum ampacity for a feeder supplying ten 30A shore power receptacles in a
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marina is _____. - 120A
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In most cases, feeder conductor size is adjusted when _____. - there are more than three
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current-carrying conductors in the raceway
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Which of the following lighting loads would be used in a residence that is 1,650 ft2? -
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4,950VA The smallest size locking and grounding type receptacle that may be used to provide
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shore power for boats is _____. - 30A
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