NCCER Load Calculations – Feeders and Services (26401-23) Practice Test

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• In a typical residential load calculation, which loads are included under lighting?
• When both heating and cooling systems are used in a building, which of the following statements is true?
• What is a practical voltage-drop limit commonly used for feeders in NCCER-type problems?
• Per NEC Table 220.56, the demand factor for eight pieces of commercial kitchen equipment is _____.
• A 15,000 ft2 office building has what minimum lighting load?
• How are transformer loads considered in load calculations for feeders and services?
• Which two NEC sections cover overhead and underground service conductor sizing and ampacity?
• Why is insulation temperature rating important when sizing conductors?
• What sized THWN copper conductors are required to supply a 120V/208V, 3 phase panelboard with 20.5 kVA of noncontinuous load and 25kVA of continuous load?
• Which NEC sections influence load calculations for feeders and services?
• Which factor must be applied when there are more than three current-carrying conductors in a single enclosure?
• A backyard pool pump house is not listed in NEC Table 220.42(A). The NEC section that applies to load calculations for this facility is _____.
• Which topic is assigned to NEC Section 240.21(C)?
• Define connected load and demand load.
• Show windows and track lighting are covered in which NEC section?
• Temperature limitations in electrical installations address which of the following?
• Which NEC section covers protection of conductors?
• A No.250 Kcmil THHN copper conductor in ambient 101 °F has an ampacity of what?
• What is the current calculation for a single-phase load given its real power P, voltage V, and power factor PF?
• Eight No.2 THHN copper conductors in a single conduit each have an ampacity of approximately which value?
• Motors, motor circuits and controllers are covered in which NEC article?
• What is the required size of THHN copper conductors for a feeder serving two 208Y/120V four wire three phase, 75°C branch circuit panelboards, one with a continuous load of 150A and the other with a noncontinuous load of 180A?
• For a single-phase load with fixed power and voltage, how does increasing the power factor toward 1 affect the current?
• Which NEC section covers underground service conductor sizing and ampacity?
• Motors, motor circuits and controllers are covered in which NEC article?
• What is a potential consequence of not converting all loads to a common basis before calculating currents?
• Which NEC section covers overhead service conductor sizing and ampacity?
• What is a consequence of not having load calculations reviewed by a qualified person?
• For a single-phase system with a load of 24 kW at 480 V and PF of 0.8, what is the current?
• The demand lighting load for a 10,000 ft2 motel with no dining room or ballroom is _____.
• Which NEC reference would you use for switchboards, switchgear and panelboards?
• How does the NCCER module 26401-23 approach training on loading calculations?
• Demand factors for 3 or more multi-family dwelling units are found in which table?
• Which per-phase ampacity value is correct for six parallel No.3/0 THHN conductors in the same conduit?
• When sizing the combined connected load for two non-coincident loads, you should use which of the following?
• What is the primary purpose of ampacity tables in the NEC?
• What is the general purpose of a demand-factor table in load calculations?
• For a 170,000 VA general lighting and small appliance load, the net load after standard demand factors is which value?
• Should heating and cooling loads be included when calculating the main service load?
• Demand factors for household electric dryers are covered in which NEC table?
• What is the voltage drop threshold for feeders alone that triggers an adjustment to feeder size?
• Which NEC element contains ampacity tables?
• The lighting load for show window feeders is calculated at how many VA per linear foot?
• Table 310.16 contains which of the following?
• In a mixed system with 120/240 V single-phase loads and 208 V three-phase loads, what must you consider in calculations?
• Where can you find information regarding outside taps of unlimited length?
• What is the total connected VA before adjustments for a dwelling with Lighting 3,000 VA; Receptacles 4,000 VA; Small-appliance circuits 2 × 1,500 VA; Water heater 4,500 VA?
• What is the load in amps for a 3-phase 480V feeder supplying a load of 112.5 kVA?
• NEC Section 430.24 covers which?
• What is the minimum general lighting load in VA for a 12,000-square-foot office building?
• Services are frequently sized larger than the required minimum size to account for _____.
• Under the 10' tap rule, the total length of the tap conductors must not exceed how many feet?
• The lighting load for dwellings and other NEC listed occupancies is generally determined by which of the following?
• Which two sources are considered when calculating lighting load for an office building?
• Which factor determines the required size of conductors to ensure safe operation under a given load?
• What is the purpose of applying demand factors to non-residential buildings?
• Noncoincident loads is covered where in the NEC?
• NEC Section 230.79 covers what?
• When finalizing feeder and service sizes, what voltage-drop consideration should be included?
• Which loads are included in sizing calculations after applying demand factors?
• What is the first step in sizing feeders and services?
• Conductor outside the building are found where?
• What is voltage drop?
• For a three-phase system, I = S/(√3 × V). If S = 180 kVA and V = 480 V, which is closest to the line current?
• Six No.3/0 THHN copper current-carrying conductors with two per phase, all in the same conduit, have what rated ampacity per phase?
• Which NEC section contains required branch circuits?
• For a restaurant kitchen with more than 6 pieces of equipment, the demand factor is what percent?
• Motors, motor circuits and controllers are covered in which NEC article?
• Demand factors for 3 or more multi-family dwelling units are covered in which NEC table?
• Which table is used for FLC for single-phase motors?
• Which topic is covered by neutral conductors in NEC?
• NEC Section 230.42 covers what?
• The general lighting load of a retail store per NEC Table 220.42(A) is _____.
• What does continuous-load adjustment account for in load calculations?
• A NEC provision discusses the minimum rating and size for feeders. Which topic is this?
• Per NEC 310.15(C)(1), the ampacity of 15 current carrying conductors must be adjusted by what percentage?
• NEC Section 230.71(B) covers which of the following?
• If the calculated load is 110 A and the service disconnect is rated 125 A, which statement is true?
• The feeder load for a show window that is 35' in length is _____.
• The general purpose receptacle of an office building is 16400VA. The demand load is _____
• What constitutes the service in a building's electrical system?
• How do you confirm that the calculated service size is compliant with field equipment ratings?
• Which table would you reference for the ampacity of insulated conductors with not more than three current-carrying conductors in a raceway or earth?
• When is a voltage-drop check performed in the sizing process?
• In a basic voltage drop calculation, what is the second step?
• What qualifies as a continuous load in NCCER load calculations?
• If a system uses 208 V three-phase loads and 120/240 V single-phase loads, what common basis should be used to sum the loads?
• When calculating the service size for a single family dwelling using the standard calculation, what part of the total general lighting and small appliance loads must be calculated at 100%?
• What is the formula to calculate current for a 3-phase load given apparent power S and line voltage V?
• What is the ampacity of a single-phase resistive load with a nameplate rating of 38.4 kW operating at 240V?
• What is the effect of applying a demand factor to a non-residential building's loads on the calculated service size?
• For a THHN feeder rated at 225A, which column from NEC table 310.16 must be used unless all components in the feeder circuit are rated for a higher temperature?
• In feeder sizing, which type of load must be increased by 125%?
• HVAC loads are covered where in the NEC?
• A school has a 150 kVA air conditioning load and a 200 kVA heating load. The value to be used when sizing the combined connected load is _____.
• A high bay manufacturing building with a wall height of 50' has a max horizontal tap length of _____.
• What is the final objective of load calculations for feeders and services?
• Which NEC section provides guidance on the rating of service disconnect means?
• How can voltage drop be minimized in feeders?
• What is the impact of ambient temperature on conductor ampacity?
• For electric space heating, feeders and services can be calculated at what percentage?
• In the NEC, the VA values used to determine lighting loads are found in which resource?
• What is the percentage of voltage drop in a 208V, 3 phase, feeder serving 200A that is 290' away and served by 4/0 THWN copper conductors?
• Which percentage adjustment applies to the ampacity when there are 15 current-carrying conductors?
• Which statement best describes the relationship between demand factor and diversity factor?
• In voltage drop considerations, how do conductor length and impedance affect voltage drop?
• A 7,500-square-foot office building requires the minimum general lighting load. What is the total in VA?
• Chapter 9, Table 8 is used to determine which aspect?
• What is the load in amps for a single-phase, 240V feeder supplying a load calculated at 23,800 VA?
• Outside taps of unlimited length are governed by which NEC section?
• A single-family dwelling has 2,000 square feet of living area. What is the minimum general lighting load in VA?
• Where can you find demand factors for non-dwelling receptacle loads?
• Which NEC section covers Windows and track lighting?
• Which of the following is considered an occupancy area and must be included in residential load calculations?
• What is the recommended practice for documenting and reviewing load calculations?
• When multiple feeders supply a building, how is the total load addressed in sizing?
• Windows and track lighting are covered in which NEC section?
• After calculating loads and applying factors, what is the next step?
• Not a typical output listed when sizing service equipment?
• In voltage drop calculation, drops are summed for feeders and branch circuits after multiplying current by distance and conductor resistance per length for how many directions?
• Small appliance and laundry loads for dwelling units are found in NEC Section?
• Which NEC reference mentions switchboards, switchgear and panelboards?
• Why are continuous loads multiplied by 125% when sizing feeders and services?
• What is covered in NEC Section 220.41?
• The general lighting load in a hotel guest room is which value?
• What does VA stand for in electrical load calculations?
• Where would you find information regarding single motors in the NEC?
• Which NEC table provides guidance for general lighting loads in non-dwelling occupancies?
• How do you determine the service size from the calculated load?
• Why is it important to align service equipment rating with the calculated load?
• A No.250 Kcmil THHN copper conductor in 101°F ambient has an ampacity of which value?
• What is the minimum service rating for a typical single-family dwelling?
• In a dwelling with two large electrical spaces featuring separate panels, how should the module sizes be determined?
• Which NEC reference addresses service disconnecting means?
• Which table addresses full load current for 3Ø motors?
• If voltage drop limits are exceeded, what is a typical remedy in design?
• What is the min general lighting load required by the NEC for a single family dwelling?
• A continuous load must be multiplied by what factor to determine feeder ampacity?
• General lighting loads for non-dwelling occupancies are detailed in which NEC resource?
• What does ampacity mean in conductor sizing?
• Which table provides the 65% demand factor for a restaurant kitchen with multiple equipment pieces?
• What is the load, in amps, for a 3 phase, 208V feeder supplying a load calculated at 96.75 kVA?
• What is covered in NEC Table 430.250?
• In sizing feeders, noncontinuous loads are considered at what percentage of their value?
• Which statement best describes when to use the 75°C column in NEC Table 310.16 for THHN copper conductors?
• What percentage factor is applied to continuous loads in sizing?
• The final sizing of feeders and services should comply with what standards?
• NEC Section 430.6(A)(1) covers which of the following?
• Other loads - All occupancies is covered where in the NEC?
• NEC Article 215 covers which electrical system component?
• Using the total connected VA, what is the feeder/service current at 240 V for a single-phase system?
• After applying continuous-load adjustment, how do you determine whether the existing service can handle the load?
• Table 310.15(B)(1)(1) covers ambient temperature correction factors based on 30°C (86°F). Which statement best describes its content?
• What data is typically required to perform a voltage-drop calculation?
• If a conductor has ampacity 75 A and the calculated load is 60 A, is the conductor adequate for the service?
• Table 220.45 covers what in the NEC?
• If a 3-phase 208V system carries a 50 kVA load, what is the current in amps?
• The rule related to overcurrent devices up to 800 A addresses which concept?
• What is the current in amps for a 3-phase 480V feeder supplying 112.5 kVA?
• Using the 10' tap rule, what size copper THWN conductor is required for a tap from a 400A, 480V, 3Phase feeder to serve a 150A load?
• Specific appliances or loads is covered where in the NEC?
• Which NEC section deals with service disconnecting means?
• For two or more motors on the same feeder, what percentage is added to the sum of motor loads?
• Which NEC section covers Feeder Taps?
• When sizing conductors for a service, at what stage is the conductor size determined?
• For a 3-phase system with a line-to-line voltage of 480 V and a load of 120 kVA, what is the line current?
• How can fault current considerations influence feeder and service sizing?
• Which statement best differentiates service equipment from feeders?
• When presenting results to a customer, which critical information should be included?
• If the 3,000 VA lighting load is continuous for 3 hours or more, how is the total adjusted?
• Which NEC section discusses motor data including rating of branch circuits and protections?
• Which NEC section covers minimum size and ampacity of differing conductors for various reasons?
• Which topic is specifically addressed by neutral conductors in the NEC?
• A 30,000 VA load is supplied by a 240V single-phase feeder. What is the current in amps?
• Single Ø dwelling services and feeders can be found in which NEC section?
• What is the common purpose of small-appliance circuits in dwelling calculations?
• Which statement is true about show window lighting load?
• When calculating voltage drop for feeders and branch circuits, what should be summed?
• Why is it essential to verify that the calculated feeder or service size does not exceed the supply utility's limitations?
• List the general steps used to size feeders and services.
• Where can you find the 25' tap rule?
• How many situations require feeder conductor size adjustments?
• In a 240 V single-phase dwelling, which voltage is used to calculate the feeder current from the total connected VA?
• Which section covers outside taps of unlimited length?
• When determining the building area for load calculations, building measurements are taken using the _____?
• Table 310.15(C)(1) addresses which of the following?
• Required branch circuits are covered in which NEC section?
• Which NEC reference covers switchboards, switchgear and panelboards?
• When sizing service equipment, what three main outputs are typically specified?
• Table 220.55 covers demand factors and loads for which appliances?
• In planning, why should you check voltage drop for long feeders first?
• Which NEC Article focuses on feeders?
• Dwelling units, min unit load is defined in which NEC section?
• A single-phase resistive load with a rating of 38.4 kW at 240 V draws how many amperes?
• Using the 25' tap rule, what is the minimum size copper THWN conductor required for a tap from a 400A, 480V, 3Phase feeder to serve a 150A load?
• How should the service disconnect rating relate to the calculated load?
• What does NEC Section 240.21(C) cover?
• What role does insulation temperature rating play in selecting conductors?
• How are general-use receptacle loads treated in load calculations for dwellings?
• A feeder supplying a lighting and appliance panelboard is sized by adding which percentages for noncontinuous and continuous loads?
• Under the 25' tap rule, conductors must be at least what fraction of the OCPD rating?
• FLC in amperes, single Ø alternating current motors are covered in which NEC table?
• In load calculations, transformer loads are included based on what parameter?
• How many conditions must be met for the 25' tap rule?
• What is the ampacity for each of 8 No.2 THHN copper conductors in a single conduit?
• Using NEC Table 220.42(A), what is the min general lighting load required by the NEC for an office building?
• What is the difference between feeder size and service size?
• Which topic would you consult to determine how feeder conductor ampacity should be adjusted for conditions other than standard temperature?
• What is the primary purpose of comparing calculated demand to acceptable limits in voltage drop calculations?
• When sizing office building lighting, you must use the larger of which two values?
• What is covered in NEC Section 240.21(B)(3)?
• How are motor loads typically handled in load calculations?
• How would you handle a scenario with both 3-phase and single-phase loads on the same service?
• Permitted reductions can be found in which part of the NEC?
• NEC Section 430.17 covers what?
• Which of the following is true about the 25' tap rule?
• The general lighting load per NEC Table 220.42(A) is used in which unit for expressing the load?
• An apartment building has a total general lighting and small appliance load of 170,000VA. Using the standard calculation, the net load after the application of demand factors is _____.
• Which NEC section specifies the table values used to determine ampacity and protections for motors, especially those under 1,200 RPM?
• Which section contains the sizing of single-phase dwelling services and feeders?
• Which building type has a minimum lighting load of 10,200 VA according to the data?
• The voltage drop percentage for a panel feeder with a noncontinuous load of 180A, using 3/0 THWN copper conductors at 480V, 3 phase, and a length of 248' is:
• Which NEC section covers windows and track lighting?
• How many conditions must be met for the 10' tap rule?
• Section 215.2(A)(2) covers which topic?