Test 2

Pataasin ang iyong marka sa homework at exams ngayon gamit ang Quizwiz!

Given, the calculated load of a retail store is 58.4 kVA, what would be the required minimum size service conductors for this three-phase 120/208 volt service (assume 75 degree terminations)? 1. 2/0 AWG 2. 1/0 AWG 3. 1 AWG 4. 2 AWG

1. 2/0 AWG

A one-family dwelling has 1500 square feet of living area, with a 12kW range and one 5.5 kW, 240 volt dryer. What 120/240 volt size service is required? 1. 60 amp 2. 100 amp 3. 125 amp 4. 150 amp

2. 100 amp

Calculate the demand factor given the following: -One-family dwelling -35,600 VA general load 1. 17,340 VA 2. 20,240 VA 3. 23,340 VA 4. 26,240 VA

2. 20,240 VA

What would be the minimum required branch circuit for a combined equipment load of: - One, 8,000 watt cooktop, - One, 6,000 watt wall-mounted oven. 1. 14,000 Watts 2. 8,800 Watts 3. 12,000 Watts 4. 6,400 Watts

2. 8,800 watts

A 3-phase, 440-volt delta system is balanced with a 25-kVA load per phase What is the line current in amperes? (75,000 VA total load) 1. 56.8 2. 98.5 3. 144.8 4. 170.5

2. 98.5

What would be minimum ampacity required to supply the following group of motors running at 208-volts, three-phase? - One (1) 15 HP wound-rotor motor, Two (2) 7.5 HP squirrel cage motors, - Three (3) 3 HP squirrel cage motors. 1. 110 amperes 2. 125 amperes 3. 150 amperes 4. 200 amperes

3. 150 amperes

According to the National Electrical Code, what would be the minimum size (smallest gauge) set of parallel THW copper conductors listed below required to serve a combined load of 920 amperes, and protected with an OCPD of 1,200 amperes? 1. Three paralleled 500 kcmil conductors 2. Two paralleled 700 kcmil conductors 3. Six paralleled 3/0 AWG conductors 4. Five paralleled 4/0 AWG conductors

3. Six paralleled 3/0 AWG conductors

Given a motor load of 1.5 horse power, that is supplied by a 115 volt power source, and is a single-phase motor, what would be the smallest allowed THHN circuit wires? 1. 8 2. 10 3. 12 4. 14

4. 14

A 1.5 horsepower, 230 volt, single phase motor that is on for more than 3 hours, shall be wired using at least a size _____ AWG type SO cord. least a size 1. 8 2. 10 3. 14 4. 16

4. 16

When a load is to continue for three hours or more, what is the maximum load that a breaker or fuse can supply, given a fuse rating of 20 amperes? 1. 26 2. 20 3. 12 4. 16

4. 16

What is the maximum number of 6 AWG THHN conductors allowed in a 1-1/4 intermediate metal conduit nipple that is 18 long? 1. 7 2. 9 3. 13 4. 19

4. 19

According to the National Electrical Code, what would be the calculated required minimum size feeder conductors type THW, given that the feeder sources the following 480 volt three-phase several motors; - One 25 HP - One 10 HP -One 5 HP 1. 10 AWG 2. 12 AWG 3. 2 AWG 4. 6 AWG

4. 6 AWG

A three-phase 460 volt feeder supplies, (1) one 10 HP squirrel cage induction motor, (1) one 20 HP wound rotor induction motor, and (1) one 30 HP wound rotor induction motor. What is the minimum feeder conductor ampacity? 1. 60 amps 2. 70 amps 3. 86 amps 4. 91 amps

4. 91 amps

What would be the minimum ampacity required for a disconnecting means of an adjustable speed drive systems, given the following conditions: - Motor: 5 HP, 230 V three-phase - ASD Rating: 17.2 amperes 1. 19.78 amperes 2. 16.70 amperes 3. 15.20 amperes 4. 10.06 amperes

1. 19.78 amperes

What is the minimum size ungrounded Aluminum Type THW conductors required for a service for the following four (4) service disconnects with 100A OCP? Disconnect 1: 92.5 amperes Disconnect_2: 83.0 amperes Disconnect_3: 83.0 amperes Disconnect_4: 45.0 amperes (Was in last exam, check wording it's tricky) 1. 500 2. 700 3. 750 4. 800

1. 500

Given. A 20-HP, 230-volt, 3-phase induction-type motor with a nameplate rating of 48 amperes marked with a temperature rise of 50 degrees C. Assuming no special increase in size for starting current is required, the maximum overload protection device rating responsive to motor current is amperes. 1. 54.0 2. 55.2 3. 60.0 4. 62.1

2. 55.2

Given An induction-type motor has the following nameplate information FLA rating of 54 amperes, temperature rise of 50 degrees C. This motor requires no special increase in the size of the overload-protection device for starting current. What is the maximum overload-protection device rating in amperes, responsive to motor current, for this motor? 1. 54 2. 62.1 3. 57.5 4. 81

2. 62.1

When considering several conductors in a ladder type cable tray, what would be the minimum size inside width given the following conductors; (12) Twelve 1250 kcmil THW single conductor cables, (6) Six 500 kcmil THW single conductor cables, (3) Three 300 kcmil THW single conductor cables. 1. 18 inches 2. 24 inches 3. 30 inches 4. 36 inches

3. 30 inches

Given: A branch circuit serves a 10-HP, 208-volt, 3-phase squirrel-cage Design-B motor. What is the maximum permitted operational setting of an adjustable inverse-time breaker protecting this branch circuit? (Assume no exceptions are applicable) 1. 30.8 amperes 2. 35.7 amperes 3. 77.0 amperes 4. 92.4 amperes

3. 77.0 amperes

A commercial building has a 120/208 volt three-phase panel sourcing various loads; including 30,000 Watts of lighting, and Twenty-five general purpose receptacles. After applying the demand for each of the load types, what would be the minimum THWN copper conductors required for this panel? 1. 2/0 AWG 2. 1/0 AWG 3. 1 AWG 4. 2 AWG

2. 1/0 AWG

What is the maximum number of 4/0 AWG THW conductors that may be installed in a 4" x 4" auxiliary metallic gutter? 1. 6 2. 8 3. 10 4. 16

2. 8

A motor that is continuous duty (operates no stop for 3 or more hours), shall be connected using a minimum size Type SO cord, given the motor is a 2 horse power, 208 volt, 3-phase motor. 1. #18 AWG 2. #14 AWG 3. #16 AWG 4. #12 AWG

3. #16 AWG

Calculate the minimum size branch circuit conductors for a single motor given the following conditions: Operating Voltage: 230 volts Electric Power: Three-Phase Motor Horsepower: 7.5 HP - Nameplate Rating: 10.0 amperes -Terminal Rating: 75-degree 1. 14 AWG 2. 12 AWG 3. 10 AWG 4. 8 AWG

3. 10 AWG

What is the minimum ampacity permitted for the branch-circuit conductors serving a 3-HP, 3-phase, induction-type, 230-volt continuous duty motor? 1. 8.0 2. 9.6 3. 12.0 4. 15.2

3. 12.0

Given, a circuit has a source voltage of 120 volts, and a resistive load of 12 Ohms, how much current will be drawn from the power source? 1. 11.2 amps 2. 11.0 amps 3. 10.2 amps 4. 10.0 amps

4. 10.0 amps

A 20 amp branch circuit which supplies lighting units may also supply appliances fastened in place only if the total rating of the appliances does not exceed 1. 10 amps 2. 12 amps 3. 16 amps 4. 20 amps

1. 10 amps

Fire pump power circuits, wiring methods, and load calculations shall comply with the requirements of the NEC. Therefore, calculate the required minimum ampacity of the conductor size, given the following multiple loads: - Fire pump motor rated at: 88 amps - Pressure maintenance pump rated at: 10.6 amps - Accessory fire equipment rated at: 10 amps 1. 133 2. 131 3. 122 4. 109

1. 133

What is the secondary current of a single phase, step-up transformer if the primary voltage is 120 volts, the secondary voltage is 600 volts, and the primary current is 10 amperes? (Assume no transformer impedance) 1. 2 amperes 2. 5 amperes 3. 10 amperes 4. 50 amperes

1. 2 amperes

When installing a nipple between two enclosures 20 inches apart, there will be (15) #12 AWG, (4) #6 AWG, and (2) #4 AWG THHN copper conductors are installed. What minimum size EMT nipple is required? 1. 3/4 inch 2. 1-1/4 inches 3. 2-1/2 inches 4. 4 inches

2. 1-1/4 inches

A controller (contactor) has been installed to control an automatically started one horsepower motor with a marked service factor of 1.15. The motor nameplate full-load current rating is 8.8 amperes. What is the maximum size overload device that may be installed in this controller? 1. 10.1 amperes 2. 11.0 amperes 3. 11.8 amperes 4. 12.3 amperes

2. 11.0 amperes

According to Table 220.55 Note 4, "the branch-circuit load for a counter-mounted cooking unit (8 kW) and two wall-mounted ovens (7 kW and 8 kW), all supplied from a single branch circuit and located in the same room, shall be calculated by adding the nameplate rating of the individual appliances and treating this total as equivalent to one range." Therefore, what is the demand load in KVA on the service? 1. 32.00 KVA 2. 12.65 kVA 3. 8.00 kVA 4. 4.40 KVA

2. 12.65 KVA

Given that a three-phase transformer will supply a load side voltage of 208-volts that draws 385 amperes of current, what would be the MINIMUM size transformer required for this service installation? 1. 200 kVA 2. 150 KVA 3. 100 kVA 4. 80 KVA

2. 150 kva

If a branch circuit supplies a single non-motor-operated appliance that is marked and rated at 20A, then the rating of overcurrent protection for the circuit shall not be greater than how many amperes? 1. 30 amperes 2. 35 amperes 3. 40 amperes 4. 45 amperes

1. 30 amperes

According to the NEC, if a plan shows a 12 foot X 12 foot bedroom which has a 3 foot door, what number of receptacles must be put in the bedroom? 1. 4 2. 5 3. 7 4. 10

1. 4

One-family dwelling consists of: -240V -Single-phase -22,800VA Net Load Given this information about this dwelling, calculate the feeder load. 1. 65 amperes 2. 85 amperes 3. 95 amperes 4. 100 amperes

3. 95 amperes

A 15-minute rated, 115 V, 2 HP, 3 phase squirrel-cage motor is to be used for intermittent duty. The minimum allowable ampacity of the branch-circuit conductors serving the motor is 1. 11.6 amps 2. 13.6 amps 3. 16.0 amps 4. 20.4 amps

1. 11.6 amps

The line current for a 208/120-volt, 3-phase, wye system, if each phase is balanced with a 2,500 VA load and the total load is 7,500 VA, is _______ amperes. 1. 12.01 2. 20.82 3. 36.05 4. 40.00

2. 20.82

Given: A 3-phase, squirrel-cage resistor-starting Design-B, 460-volt, 50-HP motor has a nameplate full-load ampere rating of 59 amperes. The overcurrent-protection device is a non-time-delay fuse. The maximum branch-circuit overcurrent (short-circuit and ground-fault) protection permitted is amperes. 1. 125 2. 180 3. 200 4. 225

3. 200

What is the maximum number of 12-2 AWG, NM cables allowed in a 21 cubic-inch box that also contains one switch? 1. 1 2. 2 3. 3 4. 4

3. 3

What would be the voltage drop across an 80 ohm resistor, given it was in series with a second resistor of 40 ohms? Assume that this series circuit is sourced from a single phase 120 volt power supply? 1. 120 volts 2. 100 volts 3. 80 volts 4. 60 volts

3. 80 volts

For a service consisting of a set of two paralleled 350-kcmil copper service entrance conductors, the minimum size aluminum grounding electrode conductor permitted from the metallic water service to the service panel is _____AWG. 1. 1/0 2. 2/0 3. 3/0 4. 4/0

4. 4/0

What would be the minimum conductor size to supply a 4,500 Watt, 240 Volt, 40-gallon hot water heater with Type TW copper conductors? 1. 6 AWG 2.8 AWG 3. 10 AWG 4. 12 AWG

3. 10 AWG

What is the maximum number of 45-degree bends permitted between junction boxes used for pull-points in a section of EMT without fittings? 1. 4 2.5 3. 6 4. 8

4.8

What would be the minimum feeder to supply the following set of four motors? - Three, 3.0 HP, single-phase, 115 volt motor. One, 7.5 HP, three-phase, 208 volt motor. 1. 66.7 amps 2. 132.25 amps 3. 112.65 amps 4. 42.5 amps

2. 132.25 amps

An overcurrent protection device must have a minimum rating of amps for a 1.5 HP, single phase, alternating current motor, operating on 115 volts, if the motor is marked with a temperature rise of 50 degrees C. 1. 15 2. 20 3. 25 4. 30

3. 25

According to the NEC, what would be the required copper grounding electrode conductor size, given that a service is installed using multiple sets of conductors in parallel? Assume that each ungrounded phase is fed with four 1/0 AWG aluminum conductors in parallel. 1. 2 AWG 2. 1/0 AWG 3. 2/0 AWG 4. 4/0 AWG

1. 2 AWG

The minimum allowable radius of the inner edge of a bend in mineral insulated metal-sheathed cable is 1. 2-1/2 in. for a 1/2-in. cable 2. 6 in. for a 1-in. cable. 3. 7 in. for a 1-in. cable : 4. 7 in. for a 1/2-in. cable.

1. 2-1/2 in. For a 1/2 - in cable

If FOUR ungrounded supply conductors are paralleled in two separate raceways, what would be the MIMIMUM supply side bonding jumper required between the 1,000 amp Service and the steel frame of the Commercial Building? Assume the individual supply conductors for this installation are size 250 kcmil conductors. 1. 2/0 AWG 2. 1/0 AWG 3. 2 AWG 4. 4 AWG

1. 2/0 AWG

Recreational vehicle electrical services and feeders shall be calculated on the basis all vehicle and tent site equipment. Therefore, calculate the 120/240-volt single-phase service load in amperes for the portion of a recreational vehicle site that has the following specifications: - Twenty-six (26) pedestals equipped with: 50 ampere receptacles Eight (8) pedestals equipped with: ONLY 20 ampere receptacles Twenty (20) dedicated tent sites with: ONLY 20 ampere receptacles 1. 480 amperes. 2. 450 amperes. 3. 400 amperes. 4. 350 amperes. Previous

1. 480 amperes

Given: Three 240-volt loads of a 15,000-VA fixed electric space heater, a 720-VA blower motor, and a 5,000-VA air conditioning unit are served from a 240-volt, single phase feeder. The minimum conductor ampacity for this feeder is _____ amperes 1. 66 2. 82 3. 91 4. 97

1. 66

According to the NEC, what would be the minimum size for the secondary conductors of a 10 kVA transformer operating at 480/240 volt single-phase configuration? 1. 8 AWG 2. 10 AWG 3. 12 AWG 4. 14 AWG

1. 8 AWG

What would be the calculated minimum required size of the supply conductors using type ZW insulation, given that the load of a 2-wire direct-current load of 33 amperes is considered continuous? 1. 8 AWG 2. 6 AWG 3. 4 AWG 4. 3 AWG

1. 8 AWG

The National Electrical Code permits the derating of the service and feeder circuits of a mobile home park. Therefore, what would be the minimum feeder given that the park will have 50 spaces (assume that the specific load details of the homes are not known)? 1. 176,000 VA 2. 184,000 VA 3. 192,000 VA 4. 200,000 VA

2. 184,000 VA

What would be the minimum grounding electrode conductor required for a 400A service that uses two paralled 3/0 AWG conductors per phase that bonds to a metal underground water pipe? (Was in the last exam ) 1. 4 AWG 2. 2 AWG 3. 1/0 AWG 4. 2/0 AWG

2. 2 AWG

The full-load current rating of a 460 V, 30-HP, 3 phase synchronous motor with a 90% power factor is 1. 32.0 amps 2. 35.2 amps 3. 40.0 amps 4. 44.0 amps

2. 35.2 amps

Using both Ohm's law and the National Electrical code as a reference for resistance, calculate the voltage. drop of the conductors that serve the following circuit load: - Service: 230 VAC Power: Single-phase - Load: 5,950 Volt-Amperes - Length: 450 feet (one-way) - Conductors: 6 AWG Raceway: Intermediate Metal Conduit 1. 22.50 volts 2. 16.97 volts 3. 11.25 volts 4 5.72 volts

3. 11.25 volts

Circuit conductors supplying power conversion equipment included as part of an adjustable speed drive system shall have an ampacity calculated to supply the loads. What would be the minimum circuit conductors given the following conditions: - Operating Voltage: 230 volts - Electric Power: Three Phase Motor Horsepower: 5 HP - ASD Rated Input Current: 17.2 amperes - Insulation Type: XHHW 1. 8 AWG 2. 10 AWG 3. 12 AWG

3. 12 AWG

Given that a single motor has an Efficiency of 90% and Power Factor of 88%, what would be the calculated minimum size the copper branch circuit conductors to source the motor listed below? - Operating Voltage: 230-volts - Electric Power: Single-Phase - Horsepower: 3 HP - Conductor Insulation Type: THHN - Nameplate Rating: 11.0 amperes - Type: Alternating-Current (AC polyphase motors) 1. 8 AWG 2. 10 AWG 3. 12 AWG 4. 14 AWG

3. 12 AWG

A 115 volt circuit has a load of 1,840 watts, how many amperes of current will flow? 1. 8 2. 12 3. 16 4. 24

3. 16

Given ten 120V, 200W incandescent luminaires. An amperage of __________ is required as a whole 1. 8 amperes 2. 7 amperes 3. 16.6 amperes 4. 22 amperes

3. 16.6 amperes

The National Electrical Code gives very specific direction for the use of supply conductors or the equivalent area usage for parallel conductors. Therefore, consider the scenario of four (4) 600 kcmil, type XHHW-2 copper ungrounded supply conductors, are connected in parallel (4 per phase) for a 1600A, 480V electrical service panel. What would be the calculated minimum Main Bonding Jumper required for this installation? 1. 600 kcmil 2. 450 kcmil 3. 300 kcmil 4. 2/0 kcmil

3. 300 kcmil

What is the minimum feeder load for 200 feet of multi-outlet strip with appliances used simultaneously? 1. 18,000 VA 2. 24,000 VA 3. 36,000 VA 4. 45,000 VA

3. 36,000 VA

Given a resistor that runs on 120 volts and is 40 ohms, the wattage is 1. 560 2. 650 3. 360 4. 420

3. 360

What is the maximum continuous load, in VA, that may be placed on a 20 ampere, 240 volt branch circuit? 1. 2400 VA 2. 2850 VA 3. 3840 VA 4. 4800 VA

3. 3840 va

How many additional cubic inches must be allowed for two clamps in a junction box, given that the wire sizes in the box are 10 AWG, 8 AWG, and 6 AWG? 1. 2 2. 4 3. 5 4. 10

3. 5

Where separate equipment grounding conductors and supply-side bonding jumpers are installed, what would be the minimum size bonding jumper for a 112 kVA rated transformer operating at 480/277 volts, three-phase that has a connected load of 100,000 volt amperes. 1. 10 AWG 2. 8 AWG 3. 6 AWG 4. 4 AWG

3. 6 AWG

The NEC states that the sum of the cross sectional areas of all contained conductors and cables at any cross section of a wireway shall not exceed 20 percent of the interior cross-sectional area of the wireway. Therefore, if a wireway is to contain only two (2) cables, each with an area of 1.6 in-sq, what would be the minimum required wireway? 1. 8 square inches 2. 11 square inches 3. 13 square inches 4. 16 square inches

4. 16 square inches

Given that a box has raceways and conductors that enter and leave the enclosure, based on the volume allowance per conductor to be installed in the box, what would be the minimum size standard box required per the NEC, given the following wires and devices will be installed? - Two (2) 12 AWG THW wires connected to a single pole switch. -Two (2) 14 AWG THW wires connected to a single pole switch. No other conductors nor fittings are installed. 1. 4 x 1 1/2 round/octagonal metal box. 2. 4 x 2 1/8 x 1 7/8 metal device box. 3. FS single cover 1 3/4 metal box. 4. 34 cubic inches, two-gang plastic box.

4. 34 cubic inches, two-gang plastic box

Given, a multi-family dwelling has twenty-two, 4,500 watt, household electric clothes dryers installed. What would be the minimum THWN aluminum feeder for this installation after derating as permitted by the National Electrical Code has been applied? 1. 1/0 AWG 2. 2/0 AWG 3. 3/0 AWG 4. 4/0 AWG

4. 4/0 AWG

According to the National Electrical Code, what would be the calculated minimum trade size equipment grounding conductor required to protect one 5 HP, 208 V, 3-phase motor? Consider all the exceptions for rating or setting for individual motor circuits, and the use of an instantaneous trip breaker. 1. 2 AWG 2. 3 AWG 3. 4 AWG 4. 6 AWG

4. 6 AWG

For a small single family dwelling of only 550 sq-ft what would be the minimum grounded (neutral) conductor? Consider that service and feeder conductors are supplied by a single-phase, 120/240-volt system, and the home has an additional electric clothes dryer. 1. 3 AWG 2. 4 AWG 3. 6 AWG 4. 8 AWG

4. 8 AWG

What would be the minimum required branch circuit for a combined equipment load of the following? - One, 7,000 watt range top - One, 8,000 watt wall-mounted oven 1. 8 kW 2. 15 kW 3. 12 kW 4. 9.2 kW

4. 9.2 kw

Using the optional method described in Article 220 of the NEC, what is the smallest feeder that can supply a multi-family building, given it has 60 units, with a 4,000 watt dryer in each unit? 1. 50 kW 2. 75 kW 3. 277 KW 4. 300 kW

2. 75 kw

A residential kitchen has a large range rated at 16,000 watts. According to the NEC, this range would have a service demand of how many watts for calculation purposes? 1. 16,000 watts 2. 9,600 watts 3. 8,000 watts 4. 6,900 watts

2. 9,600 watts

A transformer: -Rated at 75kVA (75,000VA) -460V -Three-phase -90% efficiency Given this information, calculate the ampacity (in amperes) for its PRIMARY conductor. 1. 82.4 amperes 2. 94.2 amperes 3. 105.4 amperes 4. 106.2 amperes

2. 94.2 amperes

A fixed storage type water heater that has a capacity of 120 gallons or less shall be considered a continuous load for the purposes of sizing branch circuits. Therefore, what would be the minimum branch circuit for an electric water heater with two elements that do NOT operate simultaneously, given the elements are 3,500 watts each, and the operate on 240 V? 1. 40 amperes 2. 30 amperes 3. 20 amperes 4. 15 amperes

3. 20 amperes

Given an office building plan that consists of 25,000 sq-ft, with no receptacles displayed on the plan. Calculate the demand load of the receptacles. 1. 22.5 kW 2. 23.25 kW 3. 25.0 kW 4. 28.5 kW

3. 25.0 kw

What would be the minimum load on a service for a 3,500 sq-ft home? (Included all required circuits and demand factors by the NEC) 1. 9,300 VA 2. 8,400 VA 3. 7,200 VA 4. 6,500 VA

3. 7,200 VA

If a feeder is to be installed using parallel conductors to reduce size, what would be the minimum set listed below? Consider the following specifications: (Was in exam ) - Conductor Type: THW Copper - Calculated load: 900 amperes Overcurrent Protection: 1000 amperes 1. 3 sets of 4 conductors per conduit of 400 kcmil with ground. 2. 3 sets of 4 conductors per conduit of 350 kcmil with ground. 3. 2 sets of 4 conductors per conduit of 600 kcmil with ground. 4. 2 sets of 4 conductors per conduit of 500 kcmil with ground.

1. 3 sets of 4 conductors per conduit of 400 kcmil with ground

The allowable ampacity of conductors must be reduced for Ambient Temperature Correction, and Adjustment Factors, using the derating tables of the National Electrical Code. Therefore, what would be the maximum conductor ampacity per wire permitted given the following installation? - Number of cable pairs: 3 - Number of conductors: Nine - Cable Type: #8-2 with ground - Insulation Type: THW - Ambient Temperature: 86 degrees F 1. 40 amperes. 2. 30 amperes. 3. 25 amperes.

1. 40 amperes

An apartment: -contains five units -16kW household electrical range for the units Given this information, calculate the load for all of the ranges in the apartment. 1. 24kW 2. 26.5kW 3. 28kW 4. 30.5kW

1. 24KW

What is the minimum number of 15 ampere, 120 volt lighting circuits required for a 12,000-square-foot apartment building? 1. 15 2. 20 3. 25 4. 30

2. 20

Determine the ventilation requirement for charging an electric vehicle in an indoor enclosed space given that a branch circuit is to supply multiple vehicles simultaneously. The installation will have one (1) space with 120/240 V, 20 A circuit, and one (1) space with 120/240 V, 30 A circuit. What is the total CFM required for these spaces? 1. 7 CFM 2. 247 CFM 3. 370 CFM 4. 493 CFM

2. 247 CFM

What size electrical metallic tubing is required for two 500 kcmil, THW, ALUM; one 300 kcmil, THW, ALUM; and one 400 kcmil, THW, ALUM? 1. 2 inches 2. 3 inches 3. 3-1/2 inches 4. 4 inches

2. 3 inches

A fixed storage-type water heater that has a capacity of 120 gal or less shall be considered a continuous load for the purposes of sizing branch circuits. Therefore, if the heater has an element with a nameplate. rating of 6kW at 240-vac single-phase, what would be the minimum fuse or breaker size to protect this circuit? 1. 40 2. 35 3. 30 4. 20.

2. 35

The maximum number of 12 AWG THHN conductors, including the equipment ground, that can be installed in a six-foot length of 3/8 flexible metal conduit with an outside fitting is 1. 3 2. 4 3. 5 4. 6

2. 4

Each outlet installed for the purpose of charging electric vehicles shall he supplied by an individual branch circuit and have adequate overcurrent protection. So if vehicle charger branch circuit is rated at 120V and 30A, what standard rated overcurrent device would be required? 1. 50 A 2. 40 A 3. 30 A 4. 20 A

2. 40 A

A fixed storage type water heater that has a capacity of 120 gallons or less shall be considered a continuous load for the purposes of sizing branch circuits. Therefore, what would be the minimum branch circuit for an electric water heater with two elements that do NOT operate simultaneously, given the elements are 3,500 watts each, and the operate on 240 V? 1. 40 amperes 2. 30 amperes 3. 20 amperes 4. 15 amperes

3. 20 amperes

Conductor ampacity must be derated based on the installation conditions of ambient temperature, and the number of conductors ran together. Therefore, calculate the following scenario; - Size of conductors: 6 AWG - Insulation type: XHHW Number of conductors: 10 - Ambient Temperature: 77 degrees F What would be the calculated maximum allowable ampacity of each conductor installed in the raceway? 1. 39.0 amperes 2. 40.0 amperes 3. 37.5 amperes 4. 65.0 amperes

3. 37.5 amperes

Given. A circuit load draws a total of 48 amperes, the resistive load on the circuit is 5 Ohms, determine source voltage for this circuit. 1. 120 volts 2. 240 volts 3. 277 volts 4. 480 volts

2. 240 volts

The NEC minimum number of 20 ampere, 120 volt branch circuits required to supply general lighting and general purpose receptacles (not small appliance receptacles in kitchen, dining room, etc.) in a 2,200-square-foot, one-family house is 1. 3 2. 4 3. 6 4. 8

1. 3

What is the calculated demand load in volt-amps off all loads, that is to be added to the service calculation, given the following loads? Use the optional method of calculation, not the standard. - 2,200 sq-ft home 12.0 kW range (240 V) -5.5 kW dryer -4.5 kW water heater -1.5 kW dishwasher - 9.8 ampere garbage disposal 1. 19,305 VA 2. 20,310 VA 3. 21.305 VA

2. 20,310 VA

Calculate the maximum standard rating overcurrent device given the conditions listed below. Using the main rule only. - Operating Voltage: 230 Volts - Electric Power: Three Phase - Motor Horsepower: 7.5 HP - Protective Device: Dual Element Fuse 1. 60 2. 45 3. 35 4. 30

2. 45

On a single-phase, 120/240 volt grounded service, if the load on one phase is 21,666.6 VA with no load on the other phase, the current in the grounded conductor is _____ amperes 1. 26 2. 46 3. 90 4. 180

4. 180

What minimum size type TW copper conductor is required for a non-motor generator arc welder with a duty cycle of 70% and rated primary current of 50 amperes? 1. 3 AWG 2. 6 AWG 3. 9 AWG 4. 12 AWG

2. 6 AWG

What are the smallest circuit conductors that can be used to limit the voltage drop to less than 3%, given the branch circuit supplies a 5 HP, single phase, 230 volt motor, that is 100 feet from the lighting panel? 1. 6 2. 8 3. 10 4. 12

2. 8

What is the minimum size rigid non-metallic Schedule 80 conduit for a single-phase, three-wire, 200 amp residential dwelling feeder using a full sized neutral and an equipment grounding conductor (all conductors are THW aluminum)? 1. 1-1/2 2. 2 3. 2-1/2 4. 3-1/2

3. 2-1/2

Using the National Electrical Code as a reference for resistance, what would be the resistance in Ohms of a conductor that is 1,500 feet in length and has the following characteristics? The conductor is size 8 AWG, Uncoated, Stranded, Copper, and is the source conductor for a direct current (DC) resistive load. 1. 2.334 Ohms 2. 1.167 Ohms 3. 0.982 ohms 4. 0.541 ohms

2. 1.167 Ohms

Calculate the range load by applying the demand factors in accordance with the correct NEC Table and any applicable footnotes, given an installation contains the following; - Construction Type: Multi family dwelling, - Service: 120/208 Volt four-wire feeder, - Power: Three-phase - Number of Ranges: 20 - Nameplate Rating: 12,000 Watts 1. 43.5 kW 2. 280.0 kW 3. 29.0 kW 14 20.0 kW

1. 43.5 kw

How many 15-amp general lighting branch circuits are required for a 2,576 sq-ft home? (Was In last exam ) 1. 5 circuits 2. 4 circuits 3. 7 circuits 4. 6 circuits

1. 5 circuits

If a motorized generator is operating at 50 volts, what would be the maximum overcurrent device to protect the equipment, given the unit has an FLC output rating of 100 A? 1. 150 amps 2. 125 amps 3. 100 amps 4. 80 amps

1. 150 amps

Calculate the minimum size of the branch circuit conductors to source a motor given the following conditions: Operating Voltage: 480 volts. Electric Power: Three Phase - Motor Horsepower: 40 HP - Nameplate Rating: 50 amperes - Duty-Cycle Service: 15 minute, Intermittent duty 1. 12 AWG. 2. 6 AWG. 3. 4 AWG. 4. 3 AWG.

2. 6 AWG

Using Ohm's Law, calculate what is the full load current for a 30 HP, 230V, three-phase synchronous with a 90% Power Factor? 1. 56 2. 63 3. 70 4. 108

2. 63

The National Electrical Code gives very specific direction for the use of supply conductors or the equivalent area usage for parallel conductors. Therefore, consider the scenario of three (3) 4/0 THWN ungrounded supply conductors are connected in parallel (per phase) for the secondary of a transformer and a panelboard, what MINIMUM size supply side bonding jumper required for this installation? 1. 4 AWG 2. 2 AWG 3. 1/0 AWG 4. 2/0 AWG

4. 2/0 AWG

Calculate the minimum size conduit for the following mixed THW and THHN conductors: - (4) 500 kcmil THW - (4) 2/0 AWG THHN Using Rigid Polyvinyl Chloride Conduit (PVC Schedule 40), the number of conductors shall not exceed that permitted by the percentage fill specified in Table 1, Chapter 9. Therefore, the installation would require what minimum trade size PVC-40? 1. 2-1/2 2. 3 3. 3-1/2 4. 4

4. 4

What would be the required standard OCPD rating given an installation is designed with a 75,000 VA transformer with a 480 Volt primary, 208/120 Volt secondary? Assume that the secondary will not have overcurrent protection (primary protection only). 1. 150 amperes 2. 125 amperes 3. 115 amperes 4. 95 amperes

2. 125 amperes

The branch circuit conductors to supply a resistance welder that has a duty cycle of 20%, with a primary current of 32 amps must be at least how many amperes? 1. 12 2. 14 3. 16 4. 18

2. 14

What is the minimum size feeder conductor needed to supply two 10-horsepower, 208-volt,Three phase Design B motors? 1. 6 AWG 2. 4 AWG 3. 2 AWG 4. 1 AWG

2. 4 AWG

A farm installation: 240V Single-phase Load #1: 18,000 VA Load # 2: 16,000 VA -Load # 3: 10,000 VA Given this information, calculate the total load/net computed load of this farm in accordance with the NEC. 1. 134.3 amperes 2. 152 amperes 3. 174.3 amperes 14 192 amperes

2. 152 amperes

What minimum length pull box would be required, given that two straight runs of one (1) 2 inch conduit, and one (1) 1-1/2 inch conduit, both enter the east side and exit the west side of the pull box? 1. 14 2. 16 3. 18 4. 20

2. 16


Kaugnay na mga set ng pag-aaral

HW 3 Ch 04 Activity: Prokaryotic Cell Structure and Function

View Set