Independent Electrical Contractors (IEC) First Year Practice Exam

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• When the leads of a voltmeter are placed across T1 and T8, the reading will be:
• A 250-watt lamp running 8 hours per day consumes how many kWh per day?
• Distinguish between series and parallel circuits with respect to current and voltage distribution.
• If a 60-watt lamp operates for 21 hours, the utility will bill for ___ kWh.
• In a multi-wire branch circuit, why does the neutral current not simply equal the sum of the two branch currents?
• What is the purpose of a bonding jumper in electrical installations?
• For a 100-Amp, 120/240-V, 3W commercial service, ___ AWG copper THHN/THWN conductors are the smallest permitted for the ungrounded conductors.
• If a voltmeter connected between T1 and T8 reads zero, which statement is true about the potential difference between T1 and T8?
• If connected to a metal water piping system, the grounding electrode conductor shall be connected at some point within the first __ of where it enters the building.
• During rough-in, what is a key consideration related to box fill?
• In a MWBC with two hot legs on opposite phases carrying equal currents, the neutral current is:
• An extension ladder should extend how many feet above the top of the building and be secured?
• When installing Cat5 cable, pulling too hard can damage which part of the cable?
• What is the minimum equipment grounding conductor size for a residential circuit that uses 14 AWG copper on a 20 A circuit?
• The grounding blade on an attachment plug is ___ than the current-carrying conductor blades.
• The number conductor permitted in 80 PVC is specified in table
• Which term best describes a service lateral running from the utility to the building?
• What are occupancy-based lighting controls?
• Which receptacles require GFCI protection in kitchens and bathrooms?
• If the power used by the element connected at T3 & T4 is 0.3 kW, what is the total power for all four elements energized?
• Why is the grounding blade on a plug typically longer than the live blades?
• What are the rules for securing NM-B cable and staples within 8 inches of a box and every 4.5 ft along the run?
• How do you determine the ampacity of a conductor using NEC tables and temperature ratings?
• Which protective device arrangement is required for MWBCs to ensure simultaneous disconnection?
• When installing audio/video/data cables, the cables should be installed in what manner?
• Which statement correctly describes NM-B conductors in wet locations?
• The conductors at point III in figure 130.101 are ___. The service point is located at the meter.
• What is voltage drop and when should you be concerned about it in branch circuits?
• Explain the purpose of bonding and where is a bonding jumper placed in a service or panel?
• Which statement describes how 240V residential circuits differ from 120V circuits?
• What is the purpose of a mechanical interlock in a transfer switch?
• GFCI protection is not typically required in which location?
• What is the primary function of a busbar in service equipment?
• Without exceptions, all metal parts of an indoor spa or hot tub must be bonded.
• Which unit is used to measure energy consumption that is commonly used to calculate electricity costs?
• To minimize conductor insulation damage and arcing during a ground fault or a short circuit, what should be minimized?
• Using Ohm's Law, what is the current I when V = 120 V and R = 24 Ω?
• Which statement about the grounding electrode conductor (GEC) is correct?
• In residential wiring, 120 V circuits usually power which loads?
• What is a pull string or fish tape and when is it used?
• In amps, how much current will flow in the circuit conductor connected to terminal 13 on the 1-pole breaker?
• Which color is typically used for a neutral conductor in the United States?
• Article ___ in the NEC covers grounding and bonding of electrical systems.
• What are the typical steps for a standard electrical rough-in inspection?
• Which term describes the boundary point between the utility’s service and the customer’s wiring?
• What is the typical amperage requirement for small-appliance circuits in kitchens?
• Home automation controllers that use radio frequency (RF) can do which of the following?
• Article ___ of the NEC is the article that gives requirements for swimming pool installations.
• Which wiring method is typically used for interior dry locations?
• Do 240V circuits require a neutral conductor in all cases?
• Plug fuses can be used on which of the following voltage systems?
• For residential service, the general-purpose lighting load is calculated at how many volt-amperes per square foot of area?
• The initial cost of metal halide luminaires is ___ than that of quartz.
• Which statement best describes the function of an AFCI?
• Where is the main service equipment typically located?
• Which of the following is a unit of energy?
• The neutral conductor carries ___ amps.
• What are the main features of a grounding electrode conductor (GEC) and typical materials used?
• A GFCI is designed to detect ground faults and interrupt to prevent shock.
• What is the purpose of a service meter and where is it located?
• Which statement best describes bonding in electrical systems?
• Which wiring method is commonly used for exposed runs and requires physical protection?
• A breaker panel is permitted to be located ___
• Noncoincident loads refer to loads that do not operate at the same time.
• When performing a voltage drop calculation for a branch circuit, which factors must you consider?
• RF-based home automation controllers can do which of the following concerning walls and signals?
• If the leads of the voltmeter are placed at T3 and T4 the meter will indicate
• Which of the following is true about interrupting devices associated with pool equipment?
• Circuit 13 is connected to the ___ busbar.
• What is the purpose of conduit bodies (K, L, T, etc.) and when are they required?
• Voltage drop in branch circuits should typically be kept below what percentage?
• An equipment grounding conductor (EGC) is the conductor that is ___.
• What is the minimum required clear working space in front of a panelboard for safe maintenance, and what is the typical NEC reference?
• Which of the following is a 3/0 AWG conductor?
• Is it permitted to run normal power conductors and optional standby power conductors in the same raceway or enclosure?
• Which of the following is not an appropriate location for a breaker panel under typical NEC practice?
• What is the minimum number of 125-volt, 15- or 20-ampere convenience receptacles that NEC requires to be installed near a permanently installed pool?
• Loads that do not operate at the same time are noncoincident loads. When calculating service load only the ___ of two noncoincident loads needs to be included.
• Is the statement 'Usually, load centers are not available with bolt-on circuit breakers' true?
• What are the safe practices for working on live circuits when lockout/tagout is not possible in an emergency?
• Which statement correctly describes box fill calculation?
• What is the purpose of an arc fault circuit interrupter (AFCI) and what are common symptoms of arcing faults?
• What is the monthly energy cost to operate a 250-watt high-pressure sodium lamp, given $0.15 per kWh, 8 hours per day, and 30 days in a month?
• The disconnect switch is fused with plug fuses and supplied from a 2-pole breaker in spaces 8-10 in the 277/480-volt, 3ø, 4-wire panel. Is this a code violation?
• GFCI protection is required in which of the following locations?
• The diameter of a 1/0 bare stranded copper conductor is approximately 0.372 inches. This data is found in which NEC reference?
• For pool-related receptacles located 6 to 10 feet from pool walls, what combination of protections is required?
• What are typical energy code considerations for lighting in kitchens and bathrooms?
• Terminations of RG-6 cable are made using which connectors (jacks)?
• On a multiwire circuit with unequal loads, what happens if the neutral conductor becomes open?
• Which statement best describes AFCI protection?
• If the two hot conductors on a MWBC carry 13 A and 16 A, the neutral current is:
• What is the minimum number of receptacles required in an unfinished basement?
• Which statement best describes the neutral conductor in a typical electrical system?
• On a multiwire branch circuit with unequal loads, which load is at greater risk of overheating if the neutral opens?
• In a series circuit, which statement is true about voltage drops across resistors?
• If one circuit on a MWBC is disconnected, what happens to the neutral current?
• Pool side receptacles are rated at what voltage?
• In a circuit where the switches prevent energizing the load in any position, the correct energization condition is which option?
• The Standard for Electrical Safety in the Workplace requires that all electrical equipment operating at over ___ volts to ground be de-energized and locked out before anyone is permitted to work on or near the equipment.
• According to NEC 250.122, what is the minimum equipment grounding conductor size for a 15 A circuit using 14 AWG copper?
• Which factor influences box fill calculations?
• The described panel operates at which voltage and phase configuration?
• Which statement best defines the relationship between conductor ampacity and circuit ampacity?
• If a portable generator provides power for frame-mounted receptacles only, what does the NEC require regarding a grounding electrode for the frame?
• The minimum size service disconnect for a single-family dwelling with a computed load of kVA is how many amperes?
• The neutral has been removed from the neutral bar in the circuit shown in the figure. the voltage dropped across lamp 2 is ___ volts
• Which NEC article deals with requirements for swimming pool installations?
• In EMT, eleven #12, five #10, and six #6 THHN/THWN conductors will be installed in a run. What is the smallest trade size EMT you can use?
• What must be ensured when wiring two hot conductors that share a neutral?
• Which statement correctly describes conductor color coding and the re-identification requirement when a white or gray conductor is used as a hot?
• Which statement best describes a multi-wire branch circuit?
• A voltmeter reads 120 V between T3 and T4. This indicates that T3 and T4 have what phase relationship?
• In a parallel circuit with resistors 8 Ω and 4 Ω connected to a 120 V supply, what is the total current drawn from the source?
• What is the main difference between a device such as a GFCI and an AFCI?
• Which statement describes a 3-wire residential service?
• Which value could plausibly represent the neutral current in amps if given as a precise measurement of 2.13 amps?
• The service disconnect is typically located where?
• What best describes a short circuit and a common residential wiring cause?
• Which term best describes a service lateral that is installed underground?
• When must a receptacle be installed on a dedicated circuit?
• For a 20 A circuit using 12 AWG copper conductors, what is the minimum required EGC size?
• How does an AFCI breaker detect arcing faults in a circuit?
• How is the lighting power density (LPD) calculated for a room if you know the room area and the total wattage of lighting installed?
• How does a multimeter measure resistance and continuity?
• For a 125-amp, 120/240-V, 3W residential service, what is the smallest copper THHN/THWN conductor size permitted for underground conductors?
• When calculating residential service load, how many volt-amperes are allowed for each branch circuit serving laundry receptacles?
• What is the basic purpose of a service disconnect and where is it typically located?
• RG-6 cable terminations are made using which type of connectors (jacks)?
• What is the THHN temperature rating commonly used for dry locations?
• If the two hot conductors on a multi-wire branch circuit carry 7 A and 7 A respectively, the neutral current is:
• What is the correct procedure to identify a service conductor using a non-contact voltage tester?
• Self-tapping sheet metal screws (TEK screws) ___ permitted to be used to connect the equipment grounding conductor to a metal box.
• In a multi-wire branch circuit where circuits 7 and 9 share a neutral, if circuit 7 draws 13 A and circuit 9 draws 16 A, what is the neutral current?
• When calculating the size of the required service, you should consult household electric clothes dryer demand factors given in Table ___.
• If there are two laundry branch circuits, each 1,500 VA, the total laundry load is ___ VA.
• A 20-amp, 120-volt duplex convenience receptacle near a pool shall be located at least how many feet from the inside edge of the swimming pool?
• From NEC table 8 ch. 9 the overall diameter of a 1/0 bare stranded copper is ___ inches
• Where is the service point located in the described system?
• Why are AFCI protections required in dwelling units and where are they typically applied?
• Why is it important to match amperage protection with conductor ampacity?
• ___ can be described as the point of demarcation between where the serving utility ends and the premises wiring begins.
• Which statement is true about the service disconnect and main disconnect?
• Which statement about bonding indoor spa metal parts is true?
• What is the difference between grounding and bonding in electrical systems?
• In a parallel circuit with 12 V and resistors 6 Ω and 3 Ω in parallel, what is the total current from the source?
• Which Code reference specifies the type of disconnecting means that can be used on a multiwire branch circuit that feeds devices mounted on the same yoke?
• A short length of EMT is run between two panels. The ampacity values for the conductors in this EMT need not be derated as long as the length of the EMT does not exceed how many inches?
• The load will be energized when the switches are in which condition
• In a series circuit with resistors 6 Ω, 12 Ω, and 3 Ω connected to 120 V, what is the total current?
• In NEC terms, how does a listed device differ from an assembled product?
• In a split-wired duplex receptacle fed by a 12/3 cable with two 20 A breakers, what happens if the neutral is removed from the receptacle?
• A disconnecting means for a swimming pool circulation pump must be installed in which location?
• What is the total resistance of two resistors in series with values 6 Ω and 3 Ω?
• Which standard requires de-energizing and lockout before work on electrical equipment above a threshold voltage?
• Receptacles that provide power for water pump motors located 6' and 10' from inside walls of the pool must meet which conditions?
• How many kilowatts does a 100-amp residential service draw when fully loaded?
• General-purpose lighting load total for a 2,500 square foot area would be how many volt-amperes?
• You have two 3-wire NM cables entering a box and one device (switch) installed. How many box fill units are required?
• What is the minimum number of 125-volt, 15- or 20-ampere convenience receptacles that NEC requires to be installed near a permanently installed pool?
• Are load centers typically available with bolt-on circuit breakers?
• If a short circuit occurs due to damaged insulation creating a low-resistance path, what is the main hazard if the fault is not addressed?
• Transfer switches use which device to prevent feedback between generator power and normal utility power?
• Which statement best describes TEK screws for EGC connections to metal boxes?
• To reduce voltage drop in a branch circuit, which action would be most effective?
• What is the required clearance around electrical service equipment and where is it specified?
• The disconnect switch in the described setup is supplied by how many hot conductors from the breaker?
• What is the purpose of a GFCI test button and how often should you test safety devices on a job site?
• Which of the following best describes safe practices when working on electrical systems on a job site?
• Which NEC annex is used to reference conduit fill calculations when all conductors are the same size?
• The NEC has limitations on where OCPDs, such as panelboard installations, can be installed due to the presence of combustible materials. These limitations are specified at ___
• When determining the minimum size of a grounding electrode conductor, which table is used?
• What is the temperature rating of THHN for wet locations?
• In box fill calculations, how are grounding conductors counted?
• A 60 W light bulb operates on 120 V. What are the current and the resistance of the bulb at rated power?