Module 3

What's the service demand load for a marina shore power facility with twenty 20A, 240V receptacles; seventeen 30A, 240V receptacles; and seven 50A, 240V receptacles?

630 a

What's the feeder and service conductor demand load in amperes for a manufactured home park with facilities for forty-two sites? The system is 120/240V, single-phase.

644 A

According to Chapter 9, Table 8, what's the cross-sectional area in circular mils for a 1 AWG conductor?

83690

Conductor resistance is determined by the ____.

All of these

The opposition to current flow is greater for alternating-current circuits than for direct-current circuits because of

All of these

The larger the cross-sectional area of a conductor, the_____ the number of paths for electrons, which lowers the resistance of the conductor.

Greater

The resistance of a conductor is directly proportional to its length.

True

What's the alternating-current ohms-to-neutral resistance of a 500 kcmil copper conductor installed in PVC conduit that's 400 ft long?

0.0108

What's the direct-current resistance in ohms for three 300 kcmil copper conductors in a parallel run that are 1,000 ft long?

0.014

What's the alternating-current ohms-to-neutral resistance for a 3 AWG copper conductor that's 100 ft long?

0.025 ohms

What's the direct-current resistance of a 1 AWG copper conductor that's 200 ft long?

0.0308

What's the minimum feeder conductor size for five 50A nonmotor Generator arc welders with duty cycles of 50 percent?

1/0 awg

A motor-generator arc welder has a primary current rating of 30A with a duty cycle of 40 percent. What's the minimum size branch-circuit conductor permitted to be used for the welder?

10 awg

A motor-generator arc welder has a primary current rating of 40A with a duty cycle of 30 percent. What's the minimum size branch-circuit conductor permitted to be used for the welder?

10 awg

A nonmotor-generator arc welder has a primary current rating of 40A with a duty cycle of 30 percent. What's the minimum size branch-circuit conductor permitted to be used for the welder?

10 awg

According to Chapter 9, Table 8, what's the cross-sectional area in circular mils for a 1/0 AWG conductor?

104600

A nonmotor-generator arc welder has a primary current rating of 30A with a duty cycle of 40 percent. What's the minimum size branch-circuit conductor permitted to be used for the welder?

12 awg

What's the general lighting load for a 200,000 sq ft warehouse?

126 kva

How many receptacle outlet strap/yokes are permitted on a 20A. 120V circuit in a commercial occupancy?

13

What's the load in amperes for five 32A, 480V, three-phase and three 26A, 480V, three-phase 70 percent duty cycle motor generator arc welders?

154 a

What's the general lighting demand load for conductor sizing for a 250,000 sq ft warehouse?

156 kva

Using the optional method, what's the service demand load in amperes for a 9,000 sq ft school having a total connected load of 175 KVA at 277 / 480V, three-phase?

166 a

What's the feeder conductor demand load for receptacles in a 20,000 sq ft office building?

20000

Using the standard method, what's the service load for a 4,000 sq ft restaurant containing the following loads?

355 a

What's the service demand load for ten 5-foot sections of multioutlet assembly not used simultaneously and five 2-foot sections of multioutlet assembly simultaneously used?

3600 va

What's the service demand load in amperes at 120/240V, single-phase for a 15,000 sq ft commercial warehouse containing the following loads?

525 a

Using the standard method, what's the service load for a 5,000 sq ft restaurant containing the following loads?

595 a

A new restaurant has a total connected lighting load of 30 kVA. The kitchen equipment includes two gas stoves, one gas grill, three gas ovens, one 75-gallon gas water heater, one 5 kW dishwasher, two 2 kW coffee makers, five 2 kW kitchen appliances on their own circuit, and ten 1.50 kVA small-appliance circuits. Using the optional method, what's the demand load in kVA for conductor sizing?

64 kva

What's the general lighting demand load for conductor sizing for a 100,000 sq ft warehouse?

66 kva

What's the general lighting load for a 100,000 sq ft warehouse?

66 kva

According to Chapter 9, Table 8, what's the cross-sectional area in circular mils for a 2 AWG conductor?

66360

What's the service demand load at 120/240V, single-phase for an RV park that has twenty 50A sites and forty-five 30A sites?

687 a

What's the direct current resistance of a 1/0 AVG aluminum conductor that's 800 ft long?

0.16

What's the direct-current resistance of a 6 AWG copper conductor that's 400 ft long?

0.20 ohms

What's the direct-current resistance of a 3 AWG aluminum conductor that's 500 ft long?

0.2015

What size branch-circuit conductors are required for a 40A resistance welder with a duty cycle of 30 percent?

10 awg

What's the feeder conductor demand load for 50 linear ft of show-window lighting?

12.5 kva

How many 20A, 120V circuits are required for one hundred noncontinuous use 20A, 120V receptacles and fifty 20A. 120V continuous duty receptacles?

13 circuits

What's the general lighting load for a 200,000 sq it hotel?

136 kva

How many 20A, 120V circuits are required for fifty noncontinuous use 20A, 120V receptacles and one hundred 20A. 120V continuous duty receptacles?

14 circuits

What's the general lighting demand load for a 20-room motel where each unit is 750 sq ft?

14.75 kva

What's the general lighting load for a 100,000 sq ft hospital before any demand factors?

160 kva

What's the service demand load in amperes at 120/240V, single phase for a 10,000 sq ft commercial warehouse containing the following loads?

375 a

What's the minimum feeder conductor size for five 30A nonmotor-generator arc welders with duty cycles of 30 percent?

4 awg

What's the minimum size feeder conductor for five 30A resetance welders with duty cycles of 50 farcent? The conductor terminals are rated 75°C.

4 awg

What's the minimum size feeder conductor for five 40A resistance welders with duty cycles of 30 percent? The conductor terminals are rated 75°C.

4 awg

What's the general lighting load for a 200,000 sq ft hospital?

320 kva

A marina shore power facility has twenty-four 20A, 250V receptacles and thirty 30A, 250V receptacles. What's the feeder/service demand load in amperes for the marina shore power outlets?

552 A

What's the service demand load for conductor sizing for the general lighting and receptacles for a 30.000 sa ft office building?

70 kva

What's the general lighting load for a 100,000 sq ft hotel?

76.5 kva

What's the alternating-current ohms-to-neutral resistance for a flow and consuming power. 500 kcmil copper conductor installed in an aluminum raceway that's 1,000 ft long?

0.032 ohms

_______ currents are small independent currents that are produced as a result of the expanding and collapsing magnalte field They flow erratically within the conductor opposing current. What's the alternating-current ohms-to-neutral resistance for a flow and consuming power.

Eddy

In alternating-current circuits, the expanding and collapsing magnetic field within the conductor induces an electromotive force that opposes the flow of alternating current. This opposition to the flow of alternating current is called "inductive reactance."

True

The alternating-current conductor resistances listed in Chapter 9. Table 9 of the NEC are different for copper and aluminum in PVC conduit. What's the total alternating-current ohms-to-neutral resistance of the circuit conductors? and for nonmagnetic and magnetic raceways.

True

The intensity of a magnetic field depends on the intensity of alternating current. The greater the current flow, the greater the overall magnetic field.

True

What's the alternating-current ohms-to-neutral resistance for a 2/0 AWG copper conductor that's 300 ft long?

0.03 ohms

A240V,40A, single-phase load is located 150 ft from an existing junction box. The junction box is located 50 ft from the panel-board and is wired with 4 AWG aluminum wire in a steel raceway. The total resistance of the two 4 AWG conductors from the panelboard to the junction box is approximately

0.05

A2-wire circuit supplies a 36A load that's located 100 ft from the panelboard. The load is wired with 1 AWG aluminum conductors in PVC conduit. What's the total alternating-current ohms-to-neutral resistance of the circuit conductors?

0.05 ohms

What's the alternating-current ohms-to-neutral resistance for three 1/0 AWG aluminum conductors run in parallel for 1,000 ft installed in a metal raceway?

0.067

What size THHN feeder conductor is required for two 40A motors, one 20A motor, and one 7A motor, with all terminals rated 75°C?

1 awg

What size THHN feeder conductor is required for one 50 hp motor, one 20 hp motor, and two 10 hp motors where all of them are rated 480V, three-phase, with terminals rated 75°C?

1/0 awg

What size conductor and short-circuit and ground-fault protective device is required for a multimotor hermetic refrigerant motor- compressor air conditioner? The nameplate minimum circuit ampacity is 22.1 0A, the maximum circuit breaker amperes are 35A, and the terminals are rated 60°C.

10 AWG conductor and a 35A breaker

What size conductor and short-circuit and ground-fault protective device is required for a multimotor hermetic refrigerant motor-compressor air conditioner? The nameplate minimum circuit ampacity is 30.10A, and the maximum circuit breaker amperes are 50A.

10 AWG conductor and a 50A breaker

Two 8 AWG copper conductors supply a 120V load that's located 225 ft from a panelboard. What's the maximum load in amperes that can be applied to these conductors without exceeding the NEC recommendation for conductor voltage drop?

10 a

What size THW conductor is required for a 5 hp, 230V, single-phase motor with terminals rated 75°C?

10 awg

What size branch circuit conductor is required for a resistance welder having a 30A primary current rating and a 50 percent duty cycle?

10 awg

What size branch-circuit conductor is required for a motor. generator arc welder having a 30A primary current rating and a 40 percent duty cycle?

10 awg

What size branch-circuit conductors are required for a 30A resistance welder with a duty cycle of 50 percent?

10 awg

What size branch-circuit conductors are required for a 7% hp, three-phase, 230V motor? The nameplate FLA is 20A, rated for 30-minute service, and used for short-time duty.

10 awg

What size branch-circuit conductors are required for a 7½ hp, three-phase, 230V motor?

10 awg

what size conductor should be used to limit voltage drop from exceeding three percent #the eauipment nameplate indicates 18A continuous load at 480V, three- phase and it's located 300 ft from the power supply?

10 awg

What size conductor and inverse time circuit breaker is required for a 7½ hp, 230V, three-phase motor?

10 awg conductor and a 60 a breaker

What size feeder protection is required for the following three motors?

100 a breaker

What's the VA load for the following five motors: 2 hp at 120V 3 hp at 208V, single-phase; 5 hp at 208V, three-phase; 30 hp at 480V, three-phase; and 50 hp at 480V, three-phase?

113588 va

Motors that have a service factor rating of 1.10 must have the overload protective device sized at not more than _____ percent of the motor nameplate ampere rating.

115

What size branch-circuit conductor is required for a resistance welder having a 50A primary current rating and a 15 percent duty cycle?

12 awg

What size branch-circuit conductors are required for a 5 hp, three-phase, 208V motor with terminals rated 75°C?

12 awg

Motors with a nameplate service factor (SF) rating of 1.15 or more must have the overload protective device sized at no more than percent of the motor nameplate current rating.

125

Motors with a nameplate temperature rise rating not over 40°C must have the overload protective device sized at no more than ______ percent of the motor nameplate current rating.

125

The primary overcurrent protection for a transformer rated 1,000V, nominal, or less, having a primary current rating of 9A or more must be set at not more than _____ percent of the primary current when using primary only overcurrent protection.

125

The branch-circuit short-circuit and ground-fault protective device for a 10 hp, 230V, single-phase motor must not exceed

125 a

The maximum size overcurrent device for primary only protection of a three-phase, 75 kVA transformer with a 480V primary and a 120/208V secondary is

125 a

Conductors are sized at current, overloads from percent of the motor full-load percent, and the motor short- circuit and ground-fault protective device (inverse time circuit breaker) is sized up to percent of the motor full-load

125,115,250

What size conductor and inverse time circuit breaker are required for a 2 hp, 230V, single-phase motor?

14 AWG conductor and a 30A breaker

What size conductor and inverse time circuit breaker are required for a 1 hp, 115V, single-phase motor with terminals rated 75°C?

14 AWG conductor and a 40A breaker

What size branch-circuit conductors are required for a 7% hp. three-phase, 230V motor? The nameplate FLA is 20A, raley for 5-minute service, used for intermittent duty, and the terminals are rated 75°C.

14 awg

What size conductors are required for a 1 hp, single-phase, 115V motor with terminals rated 75°C?

14 awg

What size conductors are required for a 2 hp, single-phase, 230V motor?

14 awg

What's the approximate distance that a 240V, 31A, single-phase load can be located from a panelboard so the voltage drop doesn't exceed three percent? The load is wired with 8 AWG copper.

145 ft.

According to Table 430.250, what's the FLC for a 5 hp, 230V, three-phase motor?

15.20 a

What's the required feeder short-circuit and ground-fault protection (inverse time circuit breaker) for two 40A motors, one 20A (15-minute duty cycle) motor, and one 7A motor?

150 a

The maximum size overcurrent device for primary only protection of a three-phase, 112.50 kVA transformer with a 480V primary and a 120/208V secondary is

175 a

What's the required feeder inverse time circuit breaker required for one 25 hp, 460V, three-phase squirrel-cage motor with a nameplate full-load current rating of 32A and a Design B service factor of 1.15; two 30 hp, 460V, three-phase wound-rotor motors with a nameplate primary full-load current rating of 38A and a nameplate secondary full-load current rating of 65A with a 40°C rise?

175 a

What's the feeder conductor demand load for 75 linear ft of show-window lighting?

18.75

What's the maximum distance a 240V, single-phase, 10A continuous load can be located from a panelboard so the voltage drop doesn't exceed three percent? The load is wired with 12 AWG conductors.

182 ft.

A75 kVA, 480V primary to 120/208V secondary, three-phase transformer with a 125A primary overcurrent device will require at least. primary conductors with terminals rated 75°C.

2 awg

What size copper conductors in a steel raceway can be usedto replace 1/0 AWG aluminum conductors that supply a 110A load? Hint: find a copper conductor with the same resistance per foot as the existing aluminum conductors.

2 awg

What size primary conductor can be used for a three-phase, 480V transformer, where the primary overcurrent protection is sized at 110A?

2 awg

What's the required feeder conductor for one 50 hp (5-minute varying duty) motor, one 10 hp motor, and two 5 hp motors where all of them are rated 480V, three-phase, with terminals rated 75°C?

2 awg

A 45KVA, 480V primary to 120/208V secondary, three-phase transformer with a 175A secondary overcurrent device will require at least secondary conductors (the secondary conductors are 10 ft long).

2/0 awg

What size primary conductor can be used for a three-phase, 480V transformer, where the primary overcurrent protection is sized at 175A?

2/0 awg

If a dual-element time-delay fuse is used for overload protection, what size fuse is required for a 5 hp, 208V, three-phase motor with a service factor of 1.15 and a motor nameplate current rating (FLA) of 16A?

20 a

Each unit of a 100-unit hotel is 12 × 15 ft. In addition, there's a 60x 20 ft office What's the service demand load for conductor sizing for lighting and receptacles?

20 kva

Calculate the service size for a light industrial manufacturing building with the following loads:

200 a

A new restaurant has a total connected load of 400 kVA and is all-electric. What's the service demand load for conductor sizing using the optional method?

210 kva

The branch-circuit conductors of a 5 hp, 230V, single-phase motor with a nameplate rating of 25A must have an ampacity of not less than____.

22 a

where the next size up duel element time delay-delaylusefont.suWent fortno starting curent of amolo, the rating or the ura, permitted to be increased but must in no case exceer percent of the motor's full-load current

225

What's the required feeder short-circuit and ground-fault protection (inverse time circuit breaker) for one 50 hp (5-minute varying duty) motor, one 20 hp motor, and two 10 hp motors where all motors are rated 480V, three-phase?

225 a

A 40A, 240V rated single-phase load is 150 ft from a junction box and the junction box is located 50 ft from a panelboard (for a total of 200 ft). If the voltage at the panelboard is 240V. what's the minimum voltage recommended by the NEC at the 40A load?

232.80

What's the maximum distance a 100A. 208V, three-phase noncontinuous load wired with 1 AWG conductors can be located from a panelboard so the voltage drop doesn't exceed three percent?

234 ft.

the standard overload protective device for a 2hp, 115V motor with a fulH0ad current rating of 24A and a nameplate rating of 21.50A must not exceed

24.7 a

what size dual-element time-delay fuses are required for a 2 hp, 230V, single-phase motor?

25 a

What's the service and feeder demand bad for conductor sizing for general lighting and receptacles for a 10,000 sq it office building with 75 receptacles?

25 kva

The size of the grounding electrode conductor for a single separately derived system must not be smaller than that identified in based on the area of the largest derived ungrounder supply conductor.

250.66

What's the service demand load for a manufactured home park containing seventy-five homes rated 14,000 VA?

264 kva

What's the general lighting demand load for conductor sizing for a 90,000 sq ft school?

270 kva

A new restaurant has a total connected load of 400 kVA and isn't all-electric. What's the service demand load for conductor sizing using the optional method?

296 kva

What's the maximum primary overcurrent device rating for a 0.50 kVA, single-phase, 240V transformer?

3 a

A single-phase, 5 hp motor is located 110 ft from a panelboard in a dry location. The nameplate indicates that the voltage is 115V and the FLA is 52A. What size conductor is required? Note: Apply the NEC recommended voltage-drop limit for this branch circuit.

3 awg

What size conductor is required for a 25 hp, 208V, three-phase fire pump motor with terminals rated 75°C?

3 awg

What size feeder conductors are required for two 7½ hp and one 15 hp, three phase, 230V motors with terminals rated 75°02

3 awg

What's the minimum feeder conductor size for five 30A motorgenerator arc welders with duty cycles of 30 percent?

3 awg

What size feeder/service conductor is required for a marina if the total derand load for each phase is 570A and the service is paralleled in two raceways?

300 kcmil

What's the calculated demand load in VA for five 49A. 240V, 40 percent duty cycle nonmotor-generator arc welders?

30747 va

What's the calculated load for a recreational vehicle park that has a total of forty sites; ten dedicated tent sites each with a 20A supply, ten sites each with a 20A supply, ten sites each with 20A and 30A supplies, and ten sites each with a 50A supply.

318 A

According to Table 430.248, what's the FC for a 5 hp, 200V, single-chase motor?

32.20 a

What's the service demand load for conductor sizing for 130 ft of show-window lighting?

33 kva

How far can a 240V, 50A, three-phase load be located from a panel board if it's fed with 3 AWG conductors and still meet the NEC recommendations for voltage drop for branch circuits?

339 ft.

What's the service demand load in VA for five 38A, 480V, 30 percent duty cycle resistance welders?

34108 va

A 75 kVA, 480V primary to 120/208V secondary, three-phase transformer with a 300A secondary overcurrent device will require at least secondary conductors (the secondary conductors are 10 ft long).

350 kcmil

What's the approximate distance a 480V, 45A, three-phase transformer, wired with 6 AWG copper can be located from a panelboard so the voltage drop doesn't exceed three percent?

375 ft.

What's the input VA of a 3 hp, 208V, single-phase motor?

3890 va

A 45 kVA, 480V primary to 120/208V secondary, three-phase transformer with a 70A primary overcurrent device will require at least _______ primary conductors with terminals rated 75°C.

4 awg

In an alternating-current system, the size of the grounding electrode conductor to a concrete encased electrode isn't required to be larger than a ____ copper conductor.

4 awg

What's the voltage drop of two 3 AWG aluminum conductors That supply a 55A, 240V single -phase load? The motor is located 95 ft from the power supply.

4.21 v

A 100A, three-phase load is located 100 ft from the panelboard and is wired with 1 AWG aluminum conductors. What's the approximate voltage drop of the circuit conductors?

4.40 v

what's the voltage drop of two 12AWG conductors supplying a 12A continuous load located 100 it from the power supply

4.75 v - 4.8 v

A 240V, 20A, single-phase load is located 100 ft from the panet-board and is wired with 10 AWG conductors. What's the voltage drop of the circuit conductors?

4.80 v.

The motor feeder conductor size for three 15 hp, 208V, three-phase motors; three 3 hp, 208V, single-phase motors; and three 1 hp, 120V, single-phase motors will be

4/0 awg

If a dual-element time-delay fuse is used for overload protection, what size fuse is required for a 30 hp, 460V, three-phase synchronous motor, with a nameplate current rating of 32A, and a temperature rise of 39°C?

40 a

What size nontime delay fuses are required for a 2 hp, 230V, single-phase motor?

40 a

What's the FLC from the NEC Tables [Table 430.247] for a 5 hp, 120V direct-current motor?

40 a

What size overcurrent device is required for a 25 hp, 208V, three- phase fire pump motor with a locked rotor current of 404A?

450 a

What's the voltage drop of two 12 AWG conductors that supply a 10A, 120V, single-phase load located 100 ft from the power supply?

4v

What's the service conductor load in amperes at 120/240 single phase for a 10,000 sg ft office building containing following loads?

541 a

According to Table 430.248, what's the FL for a 5 hp, 115V, Single-phase motor?

56 v

What's the maximum primary overcurrent device rating for a 2.50 kVA, 480V, single-phase transformer?

6 a

A load is located 100 ft from a 240V power supply and is wired with 4 AWG aluminum conductors. What size copper conduc- tors can be used to replace the aluminum conductors without increasing the conductor voltage drop?

6 awg

What size feeder conductors are required for a 5 hp and 3 hp, single-phase, 230V motor?

6 awg

If the branch-circuit supply voltage is 208V, the maximum recommended voltage drop of the circuit shouldn't be more than ____

6.24 v.

A 2 hp, 120V motor requires a _____ branch-circuit short-circuit and ground-fault protective device. Note: Use an inverse time breaker.

60 a

Using the optional method, what's the service demand load in amperes for a 5,000 sq ft all-electric restaurant containing the following loads?

648 A

According to Table 430.250 what's the FLC for a 25 hp, 230V, three-phase motor?

68 a

ithe feeder supply voltage is 240V. the maximum recommended voltage drop of the feeder shouldn't be more than

7.2 v.

The maximum size overcurrent device for primary only protection of a three-phase, 37.50 KVA, delta delfa configured transtome with a 480V primary and a 120/240V secondary is

70 a

The maximum size overcurrent device for primary only protection of a three-phase, 45 KVA transformer with a 480V primary and a 120/208V secondary is

70 a

The branch-circuit short-circuit and ground-fault protection (circuit breaker) for a 125 hp, 240V, direct-current motor iS

700 a

A 480V, 28A, three phase load is located 300 ft from the panel board. What size copper conductors are required to prevent the voltage drop from exceeding three percent?

8 awg

What size branch -circuit conductors are required for a 25 hp. three-phase, 460V motor with terminals rated 75°C2

8 awg

What size branch-circuit conductor is required for a direct. current rectified nonmotor-generator arc welder having a 50A primary current rating and a 60 percent duty cycle?

8 awg

What size conductors are required for a 5 hp, single-phase, 208V motor?

8 awg

What size conductors are required for a 5 hp, single-phase, 230V motor?

8 awg

What size feeder conductors are required for two 7V2hp. three phase, 230V motors with terminals rated 75°0%'

8 awg

What size primary conductor can be used for a three-phase, 480V transformer, where the primary overcurrent protection is sized at 50A with terminals rated 75°C?

8 awg

asingle phase, shoalesthat frated 110 F from a panelboard. 12. Ang nameplate indicales that the voltage is 230V and an fla or 26 a. recommended voltage-drop limits.

8 awg

What's the maximum primary overcurrent device rating for a 25 kVA continuously loaded, three-phase, 240V transformer?

80 a

what size inverse time circuit breaker is required for a 5 hp. 208V, single-phase motor?

80 a

What size feeder protection is required for the following two motors?

80 a breaker

A 240V, 24A, single-phase load is located 160 ft from the panelboard. The load is wired with 10 AWG conductors. What's the approximate voltage drop of the branch-circuit conductors?

9.50 v

There are three motors; one 5 hp, 230V, single-phase motor with a service factor of 1.20; and two 1½ hp, 120V, single-phase motors. Using an inverse time breaker, the 3-wire feeder conductor protective device after balancing all three motors will be

90 a

What's the maximum recommended continuous load that should be placed on 1/0 AWG aluminum conductors in a nonmetallic raceway to a panelboard located 200 ft from a 240V, single-phase power source so the NEC recommendation for voltage drop isn't exceeded?

90 a

Which parts) of Article 430 contains the requirements for motor short-circuit and overload protection?

A and B

Feeder conductors that supply several motors must have an ampacity of not less than

A and b

Motor feeder conductors for more than one motor (sized according to 430.24) must have a feeder protective device to protect against short circuits and ground faults (not overloads) sized not greater than the

A and b

The branch-circuit short-circuit and ground-fault protective device is intended to protect the motor, the motor control apparatus, and the conductors against overcurrent due to

A and b

How can conductor voltage drop be reduced?

All of these

To determine the percentage of the motor FL from Table 430.52 that's to be used to size the motor branch-circuit short-circuit and ground-fault protective device, which of the following steps should be used?

All of these

In addition to overload protection, each motor and its accessories require branch-circuit short-circuit and ground-fault protection according to 430.52. When sizing the branch-circuit protective device, which of the following factors must be considered?

All of these.

Overload is the condition where the current is greater than the equipment rating, resulting in equipment damage due to dangerous overheating [Article 100]. Overload protective devices, sometimes called "heaters," are intended to protect the ______ from dangerous overheating.

All of these.

The connection of the system bonding jumper for a separately derived system must be made ___ on the separately derivedsystem from the source to the first system disconnecting means or overcurrent device.

At any single point

What's the input VA of a dual voltage, 5 hp, three-phase motor rated 460/230V?

B and c

The cross-sectional area of a conductor is commonly expressed in _____

Circular mils

The NEC requires motor overload protective devices to be sized according to the motor full-load current ratings listed in Tables 430.247, 430.248, or 430.250.

False

The grounding electrode conductor for a single separately derived system is used to connect the grounded conductor of the derived system to the system bonding jumper.

False

The total opposition to current flow in an alternating-current circuit is expressed in ohms and is called

Impedance

The NEC requires motor branch-circuit short-circuit and ground-fault protection to be sized not greater than the percentages listed in Table 430.52. When the branch-circuit short-circuit and ground-fault protective device value determined from Table 430.52 doesn't correspond with the standard rating of overcurrent devices as listed in 240.6(A), the next device size is permitted to be used.

Larger

The resistance of a conductor changes with temperature. Temperature coefficient describes the effect temperature has on the resistance of a conductor. Conductors with a _____ temperature coefficient have an increase in resistance with According to Chapter 9, Table 8, what's the cross-sectional area in circular mils for a 1 AWG conductor? increase in temperature.

Positive

The expanding and collapsing magnetic field induces a counter voltage within the conductors, which repels the flowing elec- tons toward the conductor surface. This is known as _____"

Skin

When sizing conductors for feeders and branch circuits, the NEC ____ that we take voltage drop into consideration.

Suggests

The resistance of a conductor is affected by temperature change. This is called the_____.

Temperature coefficient

If the motor overload protection relay sized according to 430.32(A)(1) isn't capable of carrying the motor starting and running current, a larger overload can be used if it's sized according to the requirements of 430.32(C).

True

Motors and their associated equipment must be protected against overcurrent (overload, short circuit, or ground fault). but because of the special characteristics of induction motors. overcurrent protection may be generally accomplished by having the overload protection separate from the short-circuit and ground-fault protection.

True

The opposition to current flow results in voltage drop. All circuits have voltage drop, simply because all conductors have resistance.

True

When a conductor resistance causes the voltage to be dropped below an acceptable point, the conductor size should be increased.

True

Calculate the service size for a light industrial manufacturing building with the following loads:

300 a

Electricity costs 13 cents per kilowatt hour. Ten metal halide high bay lights draw 2A each at 240V for 12 hours a day, five a four-week period? days a week. How much will it cost to use these lights during

$149.76

What's the direct-current resistance of a 3 AWG aluminum conductor that's 1,000 ft long?

.403 ohms

What's the service demand load in amperes for five 32A, 480V. three-phase and three 26A, 480V, three-phase 50 percent duty cycle resistant welders?

110 a

Using the optional method, what's the service demand load in amperes for a 6,000 sq ft school having a total connected load of 150 kVA at 277/480V, three-phase?

123 a

What's the feeder conductor demand load for 200 linear ft of show window lighting?

15 kva

Calculate the service load in amperes for a light industrial manufacturing facility containing the following loads. The system is 277/480V, three-phase.

193 a

If there are 100 receptacle outlets in the hall and other areas of a motel (not including the motel rooms), the demand load added to the service for these receptacles is ____.

14000 va

What's the minimum feeder conductor size for five 50A motor generator arc welders with duty cycles of 50 percent?

2/0 awg

What's the direct curent resistance of a 1 AWG copper conductor that's 100 ft long?

0.0154

According to Chapter 9, Table 8, what's the cross-sectional area in circular mils for a 4 AWG conductor?

41740

What's the service demand load in amperes at 120/240/ Sole phase for a mobile home park that has thirty sites with a demand load of 42.450 VA for each site, and twenty siles With a minimum Code demand load for each?

1527 a

According to Chapter 9, Table 8, what's the cross-sectional area in circular mils for a 3/0 AWG aluminum conductor?

167800

What's the general lighting demand load for conductor sizing for a 3,200 sq ft exercise center?

4480 va

What's the feeder demand load for conductor sizing for an electric sign circuit?

1500 va

What's the service demand load for conductor sizing for 110 receptacle strap/yokes (15A or 20A. 125V) in a commercial building?

15 kva

Calculate the service load in amperes for a light industrial manufacturing facility containing the following loads. The system is 277/480V, three-phase.

151 a

Using the optional method, what's the service load in amperes for a 4.000 sq it not all-electric restaurant containing the following loads?

433 a

The National Electrical Code lists the resistance and area in circular mil for both direct-current and alternating-current conductors. Direct-current conductor resistances are listed in Chapter 9, Table ____ and alternating-current conductor resistances and reactance are listed in Chapter 9. Table ______.

8,9

What's the service demand load in KVA for a recreational vehicle park with forty-two sites where nine sites are equipped with 50A, 120/240V supply facilities; thirty sites are equipped with 20A and 30A, 120V supply facilities; and three sites are equipped with 20A, 120V supply facilities?

91.5 kva