Test 1
Over current protection for resistance-type heating elements in electric space-heating equipment shall be protected at not more than how many amperes? (Came up last exam ) A 100 Amperes B 60 Amperes C 40 amperes D 20 amperes
B 60 amperes
According to the National Electrical Code Chapter 9, Table 8 Conductor Properties what would be the calculated direct-current resistance of a conductor at 75 deg C given that the length of the wire is 100 feet of uncoated copper stranded 8 AWG wire? (Was in last exam) 1. 0.0778 ohms 2. 0.6640 ohms 3. 0.5670 ohms 4. 0.4780 ohms
1. 0.0778 ohms
Residential branch circuits rated at 120 Volts or less with GFCI protection and a maximum overcurrent protection of 20 amps must be installed at least how far below the surface grade? 1. 12 2. 16 3. 24 4. 30
1. 12
What would be the calculated minimum size of the branch circuit conductors to source a Design B energy efficient AC motor given the following conditions? -Operating Voltage: 208-volt Electric Power: Three-phase - Motor Horsepower: 5 HP - Nameplate Rating: 15.9 amperes - Rating and Duty-Cycle Service: Continuous rated, Intermittent duty (Was in last exam) 1. 12 AWG 2. 10 AWG 3. 8 AWG 4. 6 AWG
1. 12 AWG
What is the allowable ampacity (current capacity) of three #1 Awg copper conductors that are insulated with THW in a raceway that is at an ambient temperature of ONLY 86 degrees F? 1. 130 amperes 2. 115 amperes 3. 100 amperes 4. 85 amperes
1. 130 amperes
What would be the minimum lighting load for a 250,000 sq-ft floor area warehouse? 1. 156,250 volt-amperes 2. 178,361 volt-amperes 3. 189,472 volt-amperes 4. 190,583 volt-amperes
1. 156,250 volt-amperes
Combustible low density cellulose fiberboard surface mount fixtures containing a ballast must be marked for this condition, or shall be spaced not less than ______ inches from the surface of the fiberboard. 1. 1.75 2. 1.50 3. 1.25 4. 1.00
2. 1.50
Given a straight pull of conduit, the length of the box shall not be less than eight times the trade size of the largest conduit. Therefore, if a 2 inch diameter conduit run of 200 feet would require what length of box? 1. 18 in. 2. 16 in.. 3. 14 in. 4. 10 in.
2. 16 in
Conductors supplying a motor compressor load in addition to other load(s) as calculated from Article 220 and other applicable articles shall have an ampacity sufficient for the other load(s) plus the required ampacity for the motor-compressor load determined in accordance with 440.33. Given this information, what would be the correct minimum wire size for a feeder that sources two (2) hermetic motor compressors with FLA of each branch rated at 30 amperes? 1. 12 AWG 2. 4 AWG 3. 3 AWG 4. 2 AWG
2. 4 AWG
The floor area shall be calculated from the outside dimensions of the building. This total area is used to calculate the minimum lighting load. Given a 100 foot by 300 foot industrial commercial building loft, what is the general lighting load? 1. 80,000 VA. 2. 60,000 VA. 3. 40,000 VA. 4. 20,000 VA.
2. 60,000 VA
In Class I, Division 1 locations, which of the following wiring methods is permitted? 1. Armored cable 2. Type MI cable 3. Service entrance cable 4. Nonmetallic sheathed cable
2. Type MI cable
The purpose of this National Electrical Code is _______ from hazards arising from the use of electricity. 1. assist in designing systems that protect persons 2. create an industry standard for installations 3. to safeguard residential and commercial installations 4. practical safeguarding of persons and property
4. practical safeguarding of persons and property
What would be the resultant load voltage after a voltage drop on the conductors due to a 100 foot distance between the source and load? The light pole (load) has a 2kW light fixture connected with 8 AWG conductors and sourced by a 240 VAC subpanel. (Was on last test) 1. 238.7 volts 2. 236.5 volts 3. 235.4 volts 4. 234.3 volts
1. 238.7 volts
An appliance such as a water heater shall be protected against overcurrent. Given the water heater operates on 240 volts, and is a load of 4,500 watts, what standard rating overload would be required? 1. 30 amps. 2. 20 amps. 3. 15 amps. 4. 10 amps.
1. 30 amps
A bonding jumper not smaller than copper or equivalent shall be connected between an antenna CATV system's grounding electrode and the power grounding electrode system. 1. 6 AWG 2. 8 AWG 3. 10 AWG 4. 12 AWG
1. 6 AWG
A general store building requires a feeder to be sized for a service using THW 75 deg C conductors. The store has the following loads: - 15.3 KVA (non-continuous) - 18.5 KVA (continuous) operating voltage is single phase 240 volts 1. #3/0 2. #2/0 3. #1/0 4. #2
2. #2/0
Connection of conductors to terminal parts (bronze clamp) must not damage the conductors and shall be made by with pressure connectors, solder lugs, or splices to flexible leads. Terminals for more than ____conductor(s) and terminal(s) used to connect aluminum shall be so identified. 1. 0 2. 1 3. 5 4. 7
2. 1
The size of the system bonding jumper for a system that supplies a Class 1, Class 2, or Class 3 circuit, and is derived from a transformer rated not more than 1000 VA, shall not be smaller than ____ AWG copper. 1. 12 AWG 2. 14 AWG 3. 16 AWG 4. 18 AWG
2. 14 AWG
What overcurrent protection would be required given an office building installation included the following loads operating at 240 VAC: - 18,120 VA (continuous) 10,350 VA (non-continuous) 1. 175 2. 150 3. 110 4. 90
2. 150
What is the maximum a cord-and-plug connected neon sign circuit load can be, given that the rating of the overcurrent device shall not be less than the noncontinuous load plus 125 percent of the continuous load? Given that the circuit is protected with a 20 amp breaker. 1. 18 amps. 2. 16 amps. 3. 12 amps. 4. 10 amps.
2. 16 amps
In order to provide reasonable efficiency of operation of equipment, the NEC states that a maximum voltage drop on both service feeders and branch circuits to the farthest outlet not exceed 5 percent. Therefore, if a 2 percent voltage drop exists in the service conductors, what is the recommended allowable voltage drop for the branch circuit conductors? 1. 2% 2. 3% 3. 4% 4. 5%
2. 3%
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. 8 AWG 2. 6 AWG 3. 4 AWG 4. 3 AWG
2. 6 AWG
What would be the calculate the maximum standard rating (not to exceed the value calculated) branch circuit, short circuit, or ground fault protective device (OCPD) given the following conditions? - Operating Voltage: 120-volt - Electric Power: Direct-Current - Motor Rating: 3 HP - Type of Motor: DC (constant voltage) - Protective Device: Instantaneous Trip Breaker 1. 80 amperes 2. 60 amperes 3. 35 amperes 14. 25 amperes
2. 60 amperes
The National Electrical Code requires that a contractor correct for ambient temperature when installing THW two conductor at 120 degrees F. What would be the multiplier for this installation? 1. 0.88 2. 0.82 3. 0.75 4. 0.67
3. 0.75
What would be the calculated total demand load in volt-amperes for a commercial building with the following fixed multi-outlet assembly appliances that are LIKELY to be used simultaneously? Continuous runs of 41, 28, 19, and 24 feet. 1. 4,032 volt-amperes 2. 9,506 volt-amperes 3. 20,160 volt-amperes 4. 33,789 volt-amperes
3. 20,160 volt-ameperes
According to the NEC, what individual overcurrent protection would be required on the primary side of a transformer, given that the transformer rating is 600 volts, and 20 amperes? Additionally, there is no secondary overload protection. 1. 16 amps 2. 20 amps 3. 25 amps 4.30 amps
3. 25 amps
The overcurrent protection for transformers shall be in accordance with NEC 450.3. Therefore, what would be the maximum standard OCPD for the secondary of a transformer with a nameplate of 75-kVA (75,000 volt-amperes), given the operating voltages of 480/120/208-volt three-phase? (Consider that the OCPD of the primary is 250 percent.) (Was in last exam) 1. 400 amperes 2. 350 amperes 3. 300 amperes 4. 175 amperes
3. 300 amperes
For communication systems, if the building has no intersystem bonding termination or has no grounding means, a ground rod or pipe not less than _____ in length and 1/2 inch in diameter is permissible. 1. 8 feet. 2. 6 feet. 3. 5 feet. 4. 4 feet.
3. 5 feet
The ampacity of the conductors from the generator terminals to the first distribution device containing over current protection must not be less than what percentage of the nameplate current rating of the generator. A 115% B 90% C 110% D 120%
A 115%
A disconnecting means for all fuses in circuits over ______ volts to ground, shall be provided with a disconnecting means on their supply side so that each circuit containing fuses can be independently disconnected from the source of power. A. 220 B. 150 C. 120 D. 24
B. 150
According to the NEC and excluding exceptions, what would be the minimum standard size fuse or breaker required for the following loads: 32 luminaries, with a nameplate of 1/2 amperes each in a duty cycle continuous duty. A. 25 amps B. 20 amos C. 16 amps D. 10 amps
B. 20 amps
A swimming pool is to be installed with the following; six continuous duty LED lights rated at 24 watts 120 VAC single-phase, one 2 HP blower pump, and one 5 HP circulation pump (both pumps running on 240 VAC single-phase). The feeder subpanel for these loads shall be protected with what minimum rating OCPD? A. 70 B. 50 C. 45 D. 35
B. 50
If a listed resistance-type instantaneous water heater (or steam boiler) is a feeder load of 144, 000 watts and is operating at 480 volts three phase how many individual dedicated branch circuits would be required for this appliance installation? A 7 circuits B 5 circuits C 2 circuits D 1 circuit
C 2 circuits
What would be minimum ampacity required for a single disconnect for the following group of motors running at 208-volt, three phase? 7 1/2 HP, 5 HP, 3 HP all are squirrel cage motors. (Came up last exam) A 24.2 amperes B. 30.5 amperes C. 51.5 amperes D. 59.2 amperes
D. 59.2 amperes
Using Ohms law, calculate the primary current of a three-phase transformer rated at 75,000 VA, given that the operating source is 460 volts, and an efficiency of 90% 1. 112.3 amperes 2. 108.5 amperes 3. 104.6 amperes 4. 95.1 amperes
3. 104.6 amperes
Given an installation of an electric discharge fixture having mogul base lamp holders served with a 30 ampere circuit. The receptacles shall be permitted to be of a lower ampere rating than the branch circuit, but not less than ______ of the luminaire full-load current. 1. 80% 2. 115% 3. 125% 4. 140%
3. 125%
Using both Ohm's law and the National Electrical code as a reference for resistance, calculate the voltage drop of the conductors that serve a load of 200 amps. Given that the voltage source and the load it sources is 540 feet apart, and the conductors are 4/0 coated, and source voltage is 480 V single-phase. 1. 6.3 volts. 2. 7.8 volts 3. 13.5 volts 4. 15.1 volts
3. 13.5 volts
Where supplied by a common service, the total load of the farm for service conductors and service equipment shall be calculated with the farm dwelling and demand factors. Given that the farm is a 240 volt single phase system with dairy installation - 18,000 VA - 16,000 VA - 10,000 VA What is the total farm load in amperes? 1. 175 amps 2. 167 amps 3. 152 amps 4. 143 amps
3. 152
Conductors in a vertical run of 200' for conduit, has a total of three (3) current carrying 2/0 AWG copper feeders installed. At what maximum distance may this run be supported? 1. 35 feet. 2. 50 feet. 3. 80 feet. 4. 110 feet.
3. 80 feet
Grounding electrode conductors for alternating current systems are required to connect the system groundED and groundING conductors to the grounding electrode system. If the UNgrounded service conductors are increase to size 350 kcmil (to correct for excessive voltage drop), what would be the minimum size grounding electrode conductor required? 1. 3/0 AWG 2. 2/0 AWG 3. 1/0 AWG 4. 2 AWG
4. 2 AWG
A swimming pool is to be installed with the following subpanel loads; Six continuous duty LED lights rated at 24 Watts 120 VAC single-phase - One 2 HP blower pump at 240 VAC single-phase - One 5 HP circulation pump 240 VAC single-phase Considering that each single-phase load is sourced with 2 conductor with ground wires (3 wires per load; hot, neutral, ground) in the same raceway, what would be the minimmum trade size Schedule 80 PVC required. 1. 2 1/2 inches 2. 2 inches 3. 1 1/2 inch 4. 3/4 inch
4. 3/4 inch
Given, a metal wireway of a wheelchair lift installation, the sum of the cross-sectional area of the individual conductors in the wireway shall not be more than percent of the interior cross-sectional area of the wireway. 1. 120 2. 80 3. 70 4. 50
4. 50
The _____ for enforcement of the NEC has the responsibility for making interpretations of the rules, for deciding on the approval of equipment and materials, and for granting the special permission contemplated in a number of the rules. 1. General Builder 2. Chief Inspector 3. Principle Design Engineer 4. Authority having jurisdiction
4. Authority having jurisdiction
What would be the secondary overcurrent protection requirement for an auto transformer that will operate on 480 volts and has an input current of 50 amperes ? A. 70 amperes B. 62 amperes C. 50 amperes D. 40 amperes
A 70 amperes
According to the nec a grounding electrode conductor can be spliced if necessary by several means including using a bolt connector ____ times A. 1 B. 2 C. 3 D. 4
A. 1
In straight pulls the length of the box or conduit body shall not be less than 8 times the trade size of the largest raceway. Therefore, what would be the required size for the box side that has 2 inch conduit entry ? A. 16 inches B. 12 inches C. 10 inches D. 4 inches
A. 16 inches
Requirements for electrical installation of equipment shall be installed ______ A. In a neat and workmanlike manner B. Be made readily accessible C. Acceptable to inspectors and building officials D. Using precautions to protect persons and property
A. In a neat and workmanlike manner
Outlet boxes used as the sole support of a ceiling-suspended (paddle) fan shall be listed and marked by their manufacturer as suitable for this purpose, and shall not support fans that weigh more than ____ A. 100 pounds B. 70 pounds C. 50 pounds D. 35 pounds
B. 70 pounds
What would be the net computed feeder load, given the single family dwelling is a total load of 22,800 volt-amperes ? Assume that the service is a 120/240 volt system. A. 190 amps B. 95 amps C. 90 amps D. 70 amps
B. 95 amps
Use ohms law to solve the following full load current problem. Load on circuit is a 1-1/2 HP nameplate, 120 volt motor, operating at 90% efficiency with a power factor of 85%. What would be the calculated FLC of this single phase motor? A. 14 amps B. 13 amps C. 12 amps D. 11 amps
C. 12 amps
What would be the calculated maximum standard rating of a motor branch circuit, short circuit, or ground fault protective device given the following conditions? Operating voltage of 120 VAC, single phase, 5 HP, Squirrel Cage, Inverse Time breaker with 75 deg C A. 225 amperes B. 200 amperes C. 150 amperes D. 140 amperes
C. 150 amperes
What would be the minimum size copper grounding electrode conductor for an alternating current system that uses parallel conductor for each phase? Each ungrounded (hot) phase of the system consists of 4 1/0 AWG aluminum wires in connected parallel (Came up last test ) A. 8 AWG B. 6 AWG C. 2 AWG D. 2/0 AWG
C. 2 AWG
If a listed resistance type instantaneous water heater (or steam boiler) is a feeder load of 144000 watts and is operating at 480 volts, 3 phase, how many individual dedicated branch circuits would be required for this applicable installation A. 7 circuits B. 5 circuits. C. 2 circuits D. 1 circuits
C. 2 circuits
According to the NEC multiple clothes dryers are permitted to be derated by a factor less than 100%, therefore, if a multi-family dwelling has five electric clothes dryers installed, what would be the total calculated demand load for this installation after derating is applied. A. 23,572 VA B. 22,461 VA C. 21,350 VA D. 20,149 VA
C. 21,350 VA