PSI Online Practice Examination
Disregarding exceptions, overcurrent devices shall be readily accessible and shall be installed so that the center of the grip of the operating handle of the switch or circuit breaker, when in its highest position, is not more than how high above the floor or working platform?
"Switches" 404.8 "Accessibility and Grouping" (A) Location 6 ft 7in
The resistance of a 1,000 watt toaster oven is 12 ohms and the resistance of a 850 watt coffee pot is 15 ohms. The appliances are connected in parallel. What is the total resistance of the two appliances? 1. 7 ohms 2. 12 ohms 3. 15 ohms 4. 27 ohms
(R1 x R2) / (R1 + R2) = (12 x 15) / (12 + 15 ) =180/27 = 6.666 Therefore : 1. 7 ohms
All employees must receive training on working in confined and enclosed spaces when working in open pits that are greater than how many feet in depth? 1. 4 feet 2. 6 feet 3. 8 feet 4. 10 feet
1. 4 feet per Google search
A fitting is a part of a wiring system that is intended primarily to perform which type of function?
100 Fitting an accessory such as a locknut, bushing,or other part of a wiring system that is intended primarily to perform a mechanical rather than an electrical function.
What is the required width of the working space in front of electrical equipment with a 22-inch width? 1. 22 inches 2. 24 inches 3. 30 inches 4. 33 inches
110.26(A)(2) The width of the working space in front of the electrical equipment shall be the width of the equipment or 30 inches, whichever is greatest.
Where an electrical vault is required or specified for conductor and equipment operating at over 600 volts , nominal, the floor when in contact directly with earth shall be constructed in what manner?
110.31(2) The floors of vaults in contract with the earth shall be of concrete that is not less than 4 inches thick.
What is the total resistance of three 20 ohm resistors in parallel?
20 ohms
What is the recommended maximum total voltage drop on both feeders and branch circuits to the farthest outlet?
210.19 (A) Info No. 4
What is the minimum branch-circuit rating for ranges of 8-3/4 kW or more? 1. 20 amperes 2. 30 amperes 3. 40 amperes 4. 50 amperes
210.19(A)(3) Household Ranges and Cooking Appliances. For ranges of 8-3/4 or more rating, the minimum branch-circuit rating shall be 40 amperes
Receptacles in residential units shall be installed such that no point measured horizontally along the floor line of any wall space is more than how far from a receptacle outlet? 1. 6 feet 2. 8 feet 3. 10 feet 4. 12 feet
210.52(A)(1) Receptacles shall be installed such that no point measured horizontally along the floor line of any wall space is more than 1.8m (6 ft.) from a receptacle outlet.
A GFCI-type receptacle is required if installed within how manhy feet from the outside edge of the sink?
210.8(A)(7) Sinks where receptacles are installed within (6ft) of the outside edge of the sink.
What is the minimum size overhead conductor that can be used for festoon lighting that is not supported by messenger wires? 1. 14 AWG 2. 12 AWG 3. 10 AWG 4. 8 AWG
225.6(B) Overhead conductors for festoon lighting shall not be smaller than 12 AWG.
What is the minimum size copper conductor permitted for use for a 6,000 volt service? 1. 10 AWG 2. 8 AWG 3. 6 AWG 4. 4 AWG
230.23(B) Overhead Service - minimum size 8AWG 230.31(B) Underground service Conductors- Minimum Size 8AWG 230.202(A) Services Exceeding 1,000 Volts: Conductor Size Service-entrance conductors shall not be smaller than 6 AWG unless in multiconductor cable. Multiconductor cable shall not be smaller than 8AWG
Disregarding exceptions, what is the minimum size copper-clad aluminum underground service conductor permitted?
230.31 Size and Rating (B) Minimum Size: The conductors shall not be smaller that 8AWG copper or 6AWG aluminum or copper-clad aluminum.
The service disconnecting means may be installed in all of the following EXCEPT.
230.7(2) Service disconnecting means shall not be installed in bathrooms.
Plug fuses shall be permitted to be used in circuits supplied by a system having a grounded neutral point where the line-to-neutral voltage does NOT exceed which of the following? 1. 125 volts 2. 150 volts 3. 250 volts 4. 300 volts
240.50 (A)(2) Circuits supplied by a system having a grounded neutral point where the line-to-neutral voltage does not exceed 150 volts.
A circuit breaker does not have an interrupter rating shown on it. What is the interrupter rating of this circuit breaker?
240.83(C) Every circuit breaker having an interrupting rating other than 5000 amperes shall have its interrupting rating shown on the circuit breaker.
If installed and routed on the outside of a raceway, the length of the equipment bonding jumper shall not exceed how many feet.
250.102(I)(2) Outside a raceway or an Enclosure. If installed on the outside the length of the bonding jumper or conductoer or equipment bonding jumper shall not exceed 6ft.
The portions of a grounding electrode conductor in a dc system that is connected to a rod or pipe shall NOT be required to be larger than which of the following? 1. 8 AWG 2. 6 AWG 3. 4 AWG 4. 2 AWG
250.166(C) shall not be required to be larger than 6 AWG copper.
Alternating-current systems of less than 50 volts shall be grounded where supplied by transformers, if the transformer supply system exceeds which of the following?
250.20(A)(1) Alternating-Current Systems of Less Than 50 Volt. Where supplied by transformers supply system exceeds 150 Volts to ground.
Where an ac system is grounded at any point, the grounded conductors shall be routed with the ungrounded conductors to each service disconnecting means and shall be connected to each disconnecting means grounded conductors terminal or bus for an ac system operating at how many volts
250.24"Grounding Service-Supplied Alternating-Current Systems(C) Grounded Conductor Brought to Service Equipment : Where an ac system operating at 1000 volts or less is grounded at any point....
High-impedance grounded neutral systems in which a grounding impedance limits the ground fault current to a low value shall be permitted for which type of system?
250.36 High-impedance grounded neutral system in whicha grounding impedance usually a resistor, limits the ground fault current to a low value shall be permitted for 3-phase ac system of 480 volts to 1000 volts
Rod-type grounding electrode of stainless steel shall have a diameter of not less than which of the following? 1. 3/8 inch 2. 1/2 inch 3. 5/8 inch 4. 3/4 inch
250.52(A)(5)(b) Rod-type grounding electrode, 5/8 inch
Equipment grounding conductors of bare or insulated aluminum or copper-clad aluminum shall not be terminated within how many inches of the earth? 1. 6 inches 2. 12 inches 3. 18 inches 4. 24 inches
250.64(A) Aluminum or Copper-Clad Aluminum Conductors shall not be terminated within 450mm (18 inches) of the earth.
A minimum of how many threads needs to be engaged if machine screws are used to fasten bonding jumpers? 1. 2 2. 3 3. 4 4. 5
250.8(A)(5) Machine screw-type fasteners that engage not less than two threads or are secured with a nut.
Which type of surge protection device is permanently connected and intended for installation between the secondary of the service transformer and the line side of the service disconnect overcurrent device?
285.23(A)(1) SPDs shall be permitted to be connected to the supply side of the service disconnect.
What is the maximum overcurrent protection for a 10 AWG copper conductor? 1. 10 amperes 2. 15 amperes 3. 20 amperes 4. 30 amperes
30 Amps
Disregarding exceptions, conductors used for direct burial applications shall be shielded if rated above which of the following? 1. 600 volts 2. 1,000 volts 3. 1,200 volts 4. 2,000 volts
310.10 (F) Direct-Burial Conductors Cables rated above 2000 volts shall be shielded.
The length of the pull box shall not be less than how many times the outside diameter, over sheath, of the largest shield or lead-cover conductor of cable entering box? 1. 30 times 2. 36 times 3. 42 times 4. 48 times
314.71(A) The length of the box shall not be less than 48 times the outside diameter over sheath of the largest shielded or lead-covered conductor or cable entering the box
Where is AC cable NOT permitted to be used?
320.12
Unless otherwise provided, MC cables shall be secured at intervals not exceeding which of the following? 1. 6 feet 2. 8 feet 3. 10 feet 4. 12 feet
330.30(B) 6 feet
Type MI conductors shall NOT be composed of which material? 1. nickel 2. copper 3. aluminum 4. nickel-coated copper
332.104 Conductors. Type MI cable conductors shall be of solid copper, nickel, or nickel-coated copper with a resistance corresponding to standard AWG and kcmil sizes.
In which application is the installation of NM cable permitted? 1. in Type III construction 2. in motion picture studios 3. as service entrance cables 4. embedded in poured cement
334.10 Uses permitted
Which type of conduit is not permitted to used to install underground service conductors?
3348.12(6) FMC Not permitted Underground or embedded in poured concrete or aggregate
Which type of service-entrance cable has a flame-resistant and moisture resistant covering? 1. Type SE 2. Type UF 3. Type TC 4. Type NM
338.2 Definitions: Type SE Service-Entranced cable having a flame-retardant, moisture-resistan covering
How many quarter bends are allowed in IMT between pull points?
342.26 There sshall not ge more than the equivalent of four bends .
In which application is red brass rigid metal conduit permitted?
344.10 (A)(2) Red brass RMC shall be permitted to be installed for direct burial and swimming pools applications
What is the minimum radii for fixed bends of 1/2 inch flexible metallic tubing.
348.24 Referred me to Table 2 Chapter 9 Column labled "Other Bends Which gives me the answer 4 inches.
Power distribution blocks installed in boxes shall be
376.56(B) Power distribution blocks installed in metal wireways shall be listed.
When combination surface metallic raceways are used for both signaling and for lighting and power circuits , the different systems shall be run in separate compartments. Which is not an acceptable means of identifying by the interior finish of the different systems 1. tagging 2. stamping 3. imprinting 4. color coding
386.70 When combination surface metallic raceways are used for both signaling and for lighting and power circuits, the different systems shall be run in separate compartments identified by stamping, imprinting, or color coding of the interior finish.
When installed in the same cable tray, cables operating at over 600 volts shall be of which type?
392.20(B)(1) Cables over 600 volts are Type MC
Snap switches directly connected to aluminum conductors shall be listed and marked CO/ ALR if rated at 1. 15 amperes or less 2. 20 amperes or less 3. 30 amperes or less 4. 40 amperes or less
404.14(C) Snap switches rated 20 amperes or less directly connected to aluminum conductors shall be listed and marked CO/ALR
For other than a totally enclosed switchboard or switchgear, what is the minimum amount of space that shall be provided between the top of an unshielded switchboard or switchgear and any combustible ceiling? 1. 18 inches 2. 24 inches 3. 30 inches 4. 36 inches
408.18(A) Clearances From Ceiling. For other than a totally enclosed switchboard of switchgear, a space not less than 900mm (3 ft.) shall be provided between the top of the switchboard or switchgear and any combustible ceiling
What is the maximum weight of a luminaire that can be supported by the screw shell of a lampholder?
410.30(A) A luminaire that weighs more than 6 lbs shall not be supported by the screw shell of a lampholder.
Lamp tie wires, mounting screws, clips, and decorative bands on glass shall not be required to be grounded if spaced at least how far from the lamp terminals?
410.42 Luminaire (s) with Exposed Conductive Parts Lamp tie wires, mounting screwsm clipsm and decorative bands on glass spaced at least (1 1/2 in.) from lamp terminals shall not be required to be grounded.
Unless part of listed decorative lighting assembly, the minimum size pendant conductor for intermediate or candelabra-base lampholders shall not be smaller than 1. 18 AWG 2. 16 AWG 3. 14 AWG 4. 12 AWG
410.54(B) Size Pendant conductors shall not be smaller thatn 14AWG for mogul-base screw shell lampholders or smaller than 18AWG for intermediat or candelabra-base lampholders
If the branch circuit supplies a single non-motor-operated appliance, the rating of overcurrent protection shall not exceed 20 amperes if the overcurrent protection rating is not marked and the appliance is rated at 1. 12.2 amperes or less 2. 13.3 amperes or less 3. 14.4 amperes or less 4. 15.5 amperes or less
422.11(E)(2) Not exceed 20 amperes if the overcurrent protection rating is not marked and the appliance is rated 13.3 amperes or less
For permanently connected appliances, the branch- circuit overcurrent device shall be permitted to serve as the disconnecting means for appliances rated aT NOT over 1. 240 volt-amperes or 1/8 hp 2. 240 volt-amperes or 1/4 hp 3. 300 volt-amperes or 1/8 hp 4. 300 volt-amperes or 1/4 hp
4230.31(A) Rated at Not over 300 Volt-Amperes or 1/8 Horse Power
For electric space heating cables, which color of lead wire is used to indicate a circuit voltage of 240 volt, nominal.
424.35 Marking of Heating Cables (1) 120V - yellow (4) 277V - brown (2) 208V - blue (5) 480 - orange (3) 240V - red
A motor controller disconnecting means shall be permitted to be out of sight of the controller for motor circuits over how many volts? 1. 600 volts, nominal 2. 800 volts, nominal 3. 1,000 volts, nominal 4. 1,200 volts, nominal
430.102(A) Exception No.1 For motor circuits over 1000 volts nominal, a controller disconnecting means lockable shall be permitted to be out of sight of the controller, provided that the controller is marked with a warning lable giving the location of the disconnecting means.
Motor-starting rheostats for dc motors operated from a constant voltage supply shall be equipped with automatic devices that with interrupt the supply before the speed of the motor has fallen to less than _____________.
430.82 (C)(2) Rheostat in Index "one-third its normal rate"
When the disconnecting means of a transformer is located remotely it must be ....
450.14 Disconnecting Means: Where located in a remote location the disconnecting means shall be lockable.
Dry-type transformers rated over which voltage shall be installed in a vault?
450.21(C) Over 35,000 Volts Dry-type transformers rated over 35,000 shall be installed in a vault.
What is the minimum permitted branch circuit overcurrent protection for a 240-volt, 5,000-watt, 60-gallon water heater? 1. 20 amperes 2. 25 amperes 3. 30 amperes 4. 35 amperes
5,000/240= 20.8 x 1.25%=26.04 Therefore: 3. 30 amperes
What is the maximum distance that the emergency controls for an attended self-service motor fuel dispensing facility shall be located from the dispensers?
514.11(B) Emergency controls as specified in 514.11(A) shall be installed at a location acceptable to the authority having jurisdiction, but controls shall not be more than 30m (100 ft.) from dispensers
A panelboard for a mobile home shall be rated not less than which of the following? 1. 30 amperes 2. 40 amperes 3. 50 amperes 4. 60 amperes
550.11 (A) Disconnecting Means. A panelboard shall be rated not less than 50 amperes....
Temporary electric power and lighting installations for holiday decorative lighting shall be permitted for period not to exceed how many days?
590(B) Temporary Installations 90 Days
Multiple nonmotor generator arc welders are being served by a branch panel. There are two 120-amperes welders with a 70% duty cycle, one 90 amperes welder with a 80% duty cycle, and one 250 -amperes welder with a 50% duty cycle. What is the minimum disconnect for this panel?
630.11(B) Refers me to 630.11(A) to use table then only take 100% of the 2 largest and 85% of the third larges which gives me 364 amperes. Look at 240.6 for Standard Fuse Size Which leads me to 400 amps.
Information technology equipment shall be permitted to be connected to a branch circuit by a power-supply cord with a maximum length of how many feet?
645.5(B)(1) Power-supply cords shall not exceed 15 ft I looked at the beginning of branch circuits Table 210.2 Specific -Purpose Branch Circuits
What is the maximum voltage drop for any branch circuit, separately derived system, operating at 120 volts line-to-line and 60 volts to ground, serving sensitive electronic equipment? 1. 1.5% 2.2.5% 3. 3.5% 4. 4.5%
647.4 (D) The voltage drop on any branch circuit shall not exceed 1.5%
For pool equipment, the disconnecting means for all ungrounded conductors shall be readily accessible and within sight from its equipment and shall be located a minimum of how many feet horizontally from the inside walls of a pool? 1. 5 feet 2. 6 feet 3. 8 feet 4. 10 feet
680.12 Maintenance Disconnecting Means Each means shall be readily accessible and within sight from its equipment and shall be located at least 1.5 m (5 ft.) horizontally from the inside walls of a pool.
Which type of electrical equipment is used to change voltage level or waveform, or both, of electrical energy? 1. module 2. inverter 3. subarray 4. charge controller
690.2 Inverter: Equipment that is used to change voltage level or waveform, or both, of electrical energy
What is the minimum sized grounding equipment conductor required for a photovoltaic system?
690.45 An equipment grounding conductor shall not be smaller that 14 AWG.
Receptacles used for circuits and equipment operating at less than 50 volts shall have a minimum rating of how many amperes?
720.6 Receptacles shall have a rating of not less than 15 amperes.
One horsepower is equal to how many watts?
746
Unlisted nonconductive outside plant optical fiber cables shall not be permitted to be installed in which type of raceways? 1. rigid metal conduit 2. flexible metal conduit 3. electrical metal conduit 4. rigid polyvinyl chloride conduit
770.48(B) Unlisted Cables and Raceways Entering Buildings 2. flexible metal conduit
Where practicable, what is the minimum amount of separation that shall be maintained between communications wires and cables on buildings and lighting conductors?
800.53 Lighting Conductors: Where practicagle, fa separation of at least (6ft.) shall be maintained between communications wires and cables on buildings and lighting conductors.
A continuous load is a load where the maximum current is expected to continue for at least how long? 1. 3 hours 2. 6 hours 3. 8 hours 4. 24 hours
Article 100 Continuous Load: A load where the maximum current is expected to continue for 3 hours or more.
A system that is connected to establish electrical continuity and conductivity is considered to be which of the following? 1. bonded 2. in series 3. grounded 4. continuous duty
Bonded Article 100
The base of a 24-foot non-self-supporting ladder shall be placed approximately how far from the vertical structure upon which it is leaning?
CAL/OSHA Pocket Guide for Construction pg 91 Ladders (I)(f) " Non self-supporting ladders shall have horizontal distance from the top support to the foot of the ladder is one-quarter the working length of the ladder.
What is the permissible noise exposure limit for an 8-hour day that, if exceeded, requires hearing protection to be provide?
Cal/OSHA Table 3 Allowable Exposure Levels to Sound (page 103) 90dBA - 8 hours
What is the minimum size EMT conduit required for three 14 AWG, six 12 AWG, and three 8AWG conductors? all wires are THHN solid wire. 1. 3/4 inch 2. 1 inch 3. 1 1/4 inch 4. 1 1/2 inch
Ch.9 Tbl. 5: 14AWG= .0097 x 3=.0291 12AWG= .0133 x 6=.0798 8AWG= ..0366 x 3=.1098 + ------ .2187 => Ch9. Tbl 4=> 3. 1 1/4 inch
Overcurrent protection for feeders and branch circuits supplying electric vehicle supply equipment shall be sized for continuous duty and shall have a rating of not less than what percentage of the maxium load of the electric vehicle supply equipment?
Continuous Duty
Which is best defined as an unintentional electrically conductive connection between an ungrounded conductor of an electrical circuity and the normally non-current-carrying conductors, metallic enclosures, metallic raceways, metallic equipment, or earth? 1. ground fault 2. bonding jumper 3. voltage to ground 4. overcurrent protection
Ground Fault. An unintentional, electrically conductive connection between an ungrounded conductor of an electrical circuit and the normally non-current-carrying conductors, metallic enclosures, metallic raceways, metallic equipment, or earth.
What is the motor nameplate FLA rating for a 5 hp single-phase motor, 230 volt with an efficiency rating of 95% and a power factor of 90%? 1. 8 amperes 2. 16 amperes 3. 19 amperes 4. 25 amperes
I = (HP x 746) /( E x %Eff x PF) = ( 5 x 746 ) / ( 230v x .95 x .90) = 18.96
The storage batteries used as a source of power for emergency system shall be of suitable rating and capacity to supply and maintain the total load for a minimum of how long? 1. 45 minutes 2. 60 minutes 3. 75 minutes 4. 90 minutes
III 700.12 (A) Storage Battery used as a source of power for emergency systems shall be of suitable rating and capacity to supply and maintain the total load for a minimum period of 1 1/2 hours. ( 4. 90 minutes)
When intermediate members ( such as balusters or additional rails) are used on scaffolding, they should NOT be more than how many inches apart?
In CAL/OSHA Pocket Guide for the Construction Industry page 69 Guardrails (A)(c)(02) The gap between the intermediate vertical members shall not be greater than 19 inches.
Exit signs, when required, shall have lettering that is a minimum of how many inches high? 1. 2 inches 2. 4 inches 3. 6 inches 4. 8 inches
NFP 5-10.2.1 Size of Sign "Exit letters not less than 6 inches high"
A resistor has the following bands (in order): orange, red, brown, silver. What is the resistor value?
Orange =3, Red=2, Brown = 1 "0", Silver stands for +/- 10% Therefore 320 + or - 32
An appliance draws 40 amperes when used on a circuit. A bad splice is discovered on the line at the appliance on one of the phase conductors. The splice has a measured resistance of 0.5 ohms. How much power is lost at the splice? 1. 200 watts 2. 400 watts 3. 600 watts 4. 800 watts
P = I^2 x R = 40^2 x .5 = 800 watts
An electrical appliance is rated at 1,500 watts, and is connected to 120 volts. What is the resistance associated with this appliance?
R= E/I, E^2/P, P/I^2 (Remember: R E I, replace E or I with P then square the other)
What is the minimum size copper-clad aluminum equipment grounding conductor for a feeder with a 100-ampere overcurrent protection device?
Table 250.122 Minimum Size Equipment Grounding Conductors for Grounding Raceway and Equipment 6AWG
What is the maximum spacing for supports of 10 AWG copper conductors located in a vertical raceway?
Table 300.19 Spacings for Conductor Support: 100 feet
What is the maximum number of 12 AWG conductors that can be used in a 4" x 1-1/2" square box? 1.9 2.10 3.11 4.12
Table 314.16(A) = > 9
Where the rated input current of the autotransformer is less than 9 amperes, what is the maximum permitted overcurrent device rating?
Table 450.3(B) Maximum Rating or Setting of Overcurrent Protection for Transfromers 1000 Volts and Less (as a Percentage of Transformer-Rated Current)
What part of a bulk storage plant is classified as Class 2, Zone 2
Table 515.3 Drainage Ditches, separators, impounding basins. pg 450
What is the greatest root-mean-square (effective) difference of potential between any two conductors of a circuit defined as? 1. voltage 2. wattage 3. ampacity 4. maximum load
Voltage
Approximately how many kilowatts are used by a three phase, 480 volt ac motor that draws a current of 52 amperes and has a power factor rating of 88%?
kW=(I x E x 1.732 x PF) / 1,000 = 38.04 kW
