NCCER Electronical Two MOD One
The EGC for a flexible metal conduit connection to a motor supplied with a 20A circuit is? A: 8 AWG copper B: 10 AWG copper C: 12 AWG copper D: 14 AWG copper
12 AWG copper
When inserting a conductor in a crimp barrel, the conductor strands should protrude by no more than? A. 1/32" B. 1/16" C. 1/8" D. 1/4"
A. 1/32"
If catalog, information is unavailable for a pulling device, do not exceed what percent of the rated braking tensile strength? A: 10% B: 20% C: 30 % D: 40%
A: 10 %
Cable trays must be bonded in accordance with NEC Section? A: 250.96 B: 300.96 C: 300.21 D: 392.60
A: 250.96
Any exposed live parts must be guarded if the motor operates at ____________ or more, between terminals? A: 50V B: 120V C: 240V D: 480V
A: 50V
A single-phase system has two legs, Leg A and Leg B. If Leg A is carrying 50A and leg B is carrying 45A, the current carried by the neutral is? A: 5A B: 45A C: 50A D: 90A
A: 5A
A 48" reel should be moved using a? A: crane B: scissor lift C: dolly D: bucket truck
A: Crane
Which of the following is true regarding reactive power? A: Reactive power preforms no work B: Reactive power is always in phase with true power C: Reactive power is measured in Watts D Reactive power is caused by harmonics in the circuit
A: Reactive power preforms no work
True power is the product of the resistor current squared and the? A: Resistance B: Voltage C: Frequency D: Reactance
A: Resistance
With a constant-torque load, the horsepower? A: Varies in direct proportion to the speed B: varies inversely with the speed C: remains constant D: lags the speed by 10 percent
A: Varies in direct proportion to the speed
Colored objects owe their color to selective? A: absorption B: Luminance C: radiance D: frequency
A: absorption
When applying right-angle mathematics to conduit bends, the distance between bends is represented by the triangles? A: hypotenuse B: side opposite C: side adjacent D: base
A: hypotenuse
To provide both lighting control and motion detection, motion detectors are often combined with? A: infrared sensors B: timing mechanisms C: sound sensors D: four-way switches
A: infrared sensors
A conduit piston must be? A: matched to the size of the conduit B: discarded after use C: attached to the conductors D: twice as wide as the conduit
A: matched to the size of the conduit
Light duty applications such as telephone systems wiring is most likely to be run in? A: monorail cable tray B: pipe rack cable tray C: wall mounted cable tray D trapeze mounted cable tray
A: monorail cable tray
Moto connection kits are selected based on the size of the? A: motor feeder cable B: overcurrent protection C: motor terminal D: motor full-load amperage
A: motor feeder cable
A heating system is most likely to use a? A: single-phase induction motor B: wound-rotor induction motor C: squirrel cage induction motor D: synchronous motor
A: single-phase induction motor
When joining PVC, apply PVC cement to? A: the end of the conduit and the fitting B: the end of the conduit only C: the fitting only D: the end of the conduit and the primer to the fitting
A: the end of conduit and the fitting
Aluminum connectors are designed with greater contact area to counteract? A: thermal expansion B: electrolysis C: aluminum oxide filming D: galvanic corrosion
A: thermal expansion
Positioning cable so that it is not under tension is known as? A: training B: bending C: racking D: crimping
A: training
In preparation for bending, large diameter PVC should be heated for? A: 2 to 3 seconds B: 2 to 3 Minutes C; 20 to 30 minutes D: 2 to 3 Hours
B: 2 to 3 Hours
The gain for a 90 degree bend with 6" radius is? A: 1.08" B: 2.58" C: 4.72" D: 6.64"
B: 2.58
If a sine is repeated ten times per half-second, its frequency is? A: 10Hz B: 20Hz C: 40Hz D: 60Hz
B: 20Hz
Which of the following is considered a separately derived system? A: A generator supplying power where the neutral is connected to the utility system. B: An emergency standby system with an isolated neutral. C: A transformer with a direct connection between the primary and the secondary. D: A transformer with switched phase conductors but a connected neutral.
B: An emergency standby system with an isolated neutral.
Which of the following is true regarding transformer cores? A: Air-core transformers are used when the voltage of the source has a frequency below 20kHz B: An iron-core transformer provides better power transfer than air-core transformer C: Laminated sheets of steel are used to increase eddy current D: The most efficient transformers have the fewest laminates
B: An iron-core transformer provides better power transfer than air-core transformer
Using NEMA frame designations, the distance from the motor feet to the shaft center line is known as? A: C dimension B: D dimension C: F dimension D: S dimension
B: D dimension
If you are using a bender and the label has worn off, you should? A; throw away B: chart the bender C: use the gain and center line distance from a similar bender D: estimate these values based on prior experience
B: chart the bender
When studying the operation of electric motors, it is important to remember that magnetic lines of force? A: form infinite, straight lines B: do not cross C: attract material with the same polarity D: pass through conductive materials only
B: do not cross
When using a motor with dynamic braking? A: the field windings are disconnected during braking action B: electromagnetic friction brakes may be required with large loads C: the braking action can be used to hold a load after it has stopped D: a large load can be braked to an immediate stop
B: electromagnetic friction brakes may be required with large loads
Suppose a loose connection has an exposed bare conductor and it contacts the edge of a metal enclosure, this is an example of? A: short circuit B: ground fault
B: ground fault
The type of electrical tape used to provide a protective overwrap for high-voltage cable is? A: liner rubber splicing tape B: high-temperature silicone rubber tape C: vinyl plastic tape D: glass cloth electrical tape
B: high-temperature silicone rubber tape
The type of bend required where conduit enters a panelboard is most likely a(n)? A: elbow B: offset C: kick D: saddle
B: offset
Time clocks are most likely to be used with? A: wall switches B: photosensors C: three-way switches D: four-way switches
B: photosensor
On a transformer schematic, dots are used to indicate? A: switches B: polarity C: number of turns D: core type
B: polarity
A voltage-sensing relay is likely to be powered by a(n)? A: isolation transformer B: potential transformer C: autotransformer D: current transformer
B: potential transformer
The Apparent Power is the result of the vector addition of the true power and the? A: power factor B: reactive power C: inductance D: phase angle
B: reactive power
Fluorescent troffers are typically a type of? A: surface-mounted lighting fixture B: recessed lighting fixture C: pendant lighting fixture D: track-mounted lighting fixture
B: recessed lighting fixture
A wye-connected motor has? A: no common points B: the coils connected in series C: the coils connected in parallel D: four coils
B: the coils connected in series
A 15 degree change in cable tray elevation is most likely require the use of? A: horizontal adjustment splice plate B: vertical adjustment splice plate C: an elbow D: a riser
B: vertical adjustment splice plate
A common color code for a 10 AWG crimp barrel is? A: Black B: yellow C: red D: blue
B: yellow
The allowable tension for soft copper cable is? A: 0.003 lbs/cmil B: 0.005 lbs/cmil C: 0.006 lbs/cmil D: 0.008 lbs/cmil
D: 0.008 lbs/cmil
Three wraps on a capstan will provide how much pulling force? A: 10 pounds B: 21 Pounds C: 48 Pounds D: 106 Pounds
D: 106 Pounds
Per NEC Section 430.32, a motor with a service factor of 1.0 must trip at? A: 175% of full load current B: 150% of full load current C: 125% of full load current D: 115% of full load current
D: 115% of full load current
A cable tray contains eight 4/0 cables, and each cable is 1.5 inch in diameter. The minimum width of the cable try is? A: 6" B: 8" C: 10" D: 12"
D: 12"
If a motor has 4 poles and is operating at a frequency of 60Hz, its synchronous speed is? A: 240rpm B: 480 rpm C: 1200 rpm D: 1800 rpm
D: 1800 rpm
If you are bonding multiple disconnects and the size of the service conductors is 1,000 kcmil in a wireway, the size of the bonding jumper is? A: 4 AWG copper B: 2 AWG copper C: 1/0 copper D: 2/0 copper
D: 2/0 copper
If the estimated pulling force is 800 pounds, the pulling rope should be rated for no less than? A: 800 pounds B: 1600 pounds C: 2400 pounds D: 3200 pounds
D: 3200 pounds
The total capacitance of three 10mF capacitors and one 5 mF capacitors connected in parallel is? A: 5mF B: 10mF C: 15mF D: 35mF
D: 35mF
The maximum sidewall pressure for a 5kV power cable per foot of bend radius is? A: 100 lbs B: 200 lbs C: 300 lbs D: 500 lbs
D: 500 lbs
A transformer has 200 turns in the primary, 100 turns in the secondary and 120VAC applied to the primary (Ep). The voltage across the secondary (Es) is? A: 480 VAC B: 240 VAC C: 120 VAC D: 60 VAC
D: 60 VAC
A shielded cable with an OD of 2" enters a junction box with an angled pull. Assuming the system operates at 5,000V, the minimum length of the box is? A: 12" B: 16" C: 48" D: 72"
D: 72"
When variable-frequency speed control is used on a motor with a nameplate rating of 480V at 60Hz, the voltage-to-frequency ratio is? A: 1 B: 2 C:4 D: 8
D: 8
A normal or low power factor ballast has a power factor of less than? A: 30% B: 50% C: 70% D: 90%
D: 90%
Which of the following coils is likely to show the highest inductance? A: A coil with few turns B: A coil with a non-magnetic core C: A coil with a narrow coil D: A coil with a short coil
D: A coil with a short coil
A receptacle in a wet location would most likely be installed in a? A: SLB B: handhole C: mogul D: FS box
D: FS box
To compare the phase angle between two waves, both waves must have the same? A: Voltage B: Current C: Potential D: Frequency
D: Frequency
An enclosure for use in area subject to regular washdown is? A: NEMA Type 1 B: NEMA Type 2 C: NEMA Type 3 D: NEMA Type 4
D: NEMA Type 4
Any ungrounded conductor that enters a raceway, box, or enclosure must be protected with an insulating bushing if it is? A: No. 10 AWG or larger B: No. 8 AWG or larger C: No. 6 AWG or larger D: No. 4 AWG or larger
D: No. 4 AWG or larger
Which of the following is least likely to result in ampacity derating of conductors in cable trays? A: number of cables B: tight cable configuration C: Covered tray D: Open tray
D: Open tray
One device that requires a sawtooth waveform is a(n)? A: Refrigerator B: Compressor C: Electric Drill D: Oscilloscope
D: Oscilloscope
The requirements for immediate supports can be found in NEC? A: Table 310.15(B)(16) B: Chapter 9 Table 8 C: Table 402.3 D; Table 300:19(A)
D: Table 300.19(A)
A circuit impedance is represented by the letter? A: I B: R C: X D: Z
D: Z
An office area in which the occupants sit quietly at desk is best suited for lighting fixtures controlled by a(n) A: motion detector B: sound sensor C: ultrasonic sensor D: infrared sensor
D: infrared sensors
When using nonmetallic boxed with Type NM cable, the grounding wire? A: must be connected to the box using a grounding clip. B: must be connected to the box using a grounding screw. C: must be connected to the box using a grounding locknut. D: is not required to be connected to the box.
D: is not required to be connected to the box.
A handhole must be? A: fully sealed on four sides regardless of type B: installed so excavation is required for access C: reinforced with iron rebar D: provided with a cover that weighs over 100 lbs or requires tools to open
D: provided with a cover that weighs over 100 lbs
In order to make a 90 degree bend in RMC, the conduit is bent to 95 degrees to account for? A: take-up B: gain C; developed length D: springback
D: springback
A type of motor used in precision application that requires constant speed with zero slip is? A: single-phase induction motor B: wound-rotor induction motor C: squirrel cage induction motor D: synchronous motor
D: synchronous motor
Which of the following is the best tool for opening a lighting fixture carton? A: screwdriver B: long knife C: utility knife D: crowbar
c: utility knife
The main bonding jumper for 3/0 service conductors is? A: 8 AWG copper B: 6 AWG copper C: 4 AWG copper D: 2 AWG copper
4 AWG copper
The power factor a circuit with a resistance of 75 ohms and impedance of 150 ohms is? A: 1.00 B: 0.75 C: 0.50 D: 0.25
C: 0.50
The minimum radius for 3 1/2 conduit using a one-shot bender is? A: 5" B: 10" C: 15" D: 30"
C: 15"
A shielded cable with an OD of 50 mm enters a junction box with an angled pull. Assuming it operates at 5,000v, the minimum length of the box is? A: 1200 mm B: 1600 mm C: 1800 mm D: 4800 mm
C: 1800 mm
A 2" raceway rubs alongside a 3" raceway into a junction box with an angle pull. Assuming the system operates at 600V; the required distance between these to raceway entries is? A: 14" B: 24" C: 20" D: 32"
C: 20"
What is the voltage (E) in a purely resistive circuit with a current drawn of 22A and a 10 ohms resistance? A: 32V B: 120V C: 220V D: 440V
C: 220V
Assuming the use of 75 degrees Celsius copper conductors, a 200A commercial services would require? A: 1/0 service conductors B: 2/0 service conductors C: 3/0 service conductors D: 4/0 service conductors
C: 3/0 service conductors
The Minimum radius for MD 91 conduit using a one-shot bender is? A: 127 mm B: 254 mm C: 381 mm D: 762 mm
C: 381 mm
You are making 12" stub-up in 1" RMC, and the bender deduct is listed at 8". Where do you make your mark from the end of the pipe? A: 2" B: 3" C: 4" D: 5"
C: 4"
The expected weight of an installed cable tray system including cables is 400 lbs. Each support must be able to carry? A: 300 lbs B: 400 lbs C: 500 lbs D: 800 lbs
C: 500 lbs
An MD 53 raceway runs alongside an MD 78 raceway into a junction box with an angled pull. Assuming the system operates at 600V; the required distance between these two raceways entries are? A: 131 mm B: 396 mm C: 521 mm D: 786 mm
C: 521 mm
When an equipment bonding jumper is installed outside, the length is limited to not more than? A: 2' B: 4' C: 6' D: 8'
C: 6'
Boxes for indoor surface-mounted wall fixtures are normally installed at? A: 4'0" B: 5'0" C: 6'0" D: 7'0"
C: 6'0"
Test mandrels should be side at percent of the conduit size? A: 20% B: 40% C: 80% D: 100%
C: 80%
HVAC equipment is often controlled by a(n)? A. photosensor B: infrared sensor C: EMS D: ultrasonic sensor
C: EMS
A transparent, semi-rigid heat-shrink insulator that provides good abrasion resistance is? A: neoprene B: Teflon C: Kynar D: PVC
C: Kynar
Which type of line is the easiest to see? A: Curved Line B: Diagonal Line C: Straight Line D: Wavy Line
C: Straight Line
A ground rod must be installed in a coastal location and can only be driven halfway before encountering a rock self. One alternative is to? A: bond and bury two 4' lengths of ground rod. B: allow the 4" section to protrude above the ground. C: bury the rod in a trench at least 30'' deep. D: bend the rod in a U shape and drive both ends into the ground.
C: bury the rod in a trench at least 30'' deep.
Pliers are a type of? A: high-MA tool B: adjustable-MA tool C: constant-MA tool D: proportional-MA tool
C: constant-MA tool
Apparent power is the product of the source voltage and the? A: resistance B: frequency C: current D: reactance
C: current
A NEMA destination for a type of enclosed motor is? A: splash-proof B: drip-proof C: explosion proof D: guarded
C: explosion proof
The lamp with the shortest life expectancy is the? A: fluorescent lamp B: HID lamp C: incandescent lamp D: halogen lamp
C: incandescent lamp
A Hydraulic bender is not maintaining its rated hydraulic pressure. This is most likely because of a(n)? A: voltage fluctuation B: insufficient bend radius C: low fluid pressure D: incorrect bending shoe
C: low fluid pressure
When using a cutting tool, a dull cutting edge? A: is safer than a sharp edge B: is less likely to cause conductor damage C: may result in slips D: is unlikely because the tool self-sharpens
C: may result in slips
Long pulls of large conductors are most likely to require the use of? A: taped connections B: basket grips C: setscrews grips D:heat-shrink grips
C: setscrew grips
A motor with the field coil connected in a parallel with the rotor winding is a? A: shielded motor B: series motor C: shunt motor D: sealed motor
C: shunt motor
When inspecting a long expanse of cable tray, you discover that tray is buckling. This is a type of? A: transverse failure B: rung failure C: side rail failure D: splice failure
C: side rail failure
The type of motor most likely to be used in a location with flammable dust and torque fluctuation is a? A: single-phase induction motor B: wound-rotor induction motor C: squirrel cage induction motor D: synchronous motor
C: squirrel cage induction motor
A delta-connected motor has? A: no common points B: the coils connected in series C: the coils connected in parallel D: four coils
C: the coils connected in parallel
When ordering cable for a conductor insulation, it is best to? A: Estimate the length required to avoid delays B: Order 3 times the anticipated length to account for terminations C: Wait until raceways have been installed to measure. D: Use a standard formula based on the square footage of the installation
C: wait until the raceway has been installed to measure
Interlocked armor cable should have a bend radius of no less than? A: twice its diameter B: three times its diameter C: 5 times its diameter D; 8 times its diameter
C; Five times its diameter
A motor with a NEMA kVA code letter of M has a locked-rotor value of? A.4.0-4.99 kVA/hp B 4.5-4.99 kVA/hp C 5.0-5.99 kVA/hp D 10.0-11.19 kvA/hp
D 10.0-11.19 kvA/hp
