NCCER Electrical
Which of these is pulled through a raceway to test for obstructions before a cable pull?
Mandrel
An insulated type 600 volt crimp terminal for a 12-10 AWG is typically identified by which color code?
Yellow
What is the voltage on the high leg in the figure?
480 volts
5. If a voltage source of a circuit provides 240 volts and there are 5 ohms of resistance, how much current is in the circuit?
48amps
.Compounds made of porcelain and plastic are used as____
insulators
The neutral bus in a sub panel
is isolated from the grounded bus
To test the insulation resistance between the heating cable conductors and the metallic grounding use a;
megohmmeter
The wattage output of series resistance heating cables depends on the total circuit length and:
resistance
What type of conduit body is characterized by a threaded straight hub on each end?
C
An assembly containing two or more insulated conductors and having an overall jacket is known as a:
Cable
Time delay fuses are MOST commonly used in circuits subject to what type of current?
Surge (in rush)
The volt amperes in an AC circuit is the same as
apparent power
In hazardous locations where metal conduit is required , the conduit MUST be threaded with
standard threads
The NEC recommends maintaining voltage within a 3% drop. If a branch circuit operates at 240 volts AC. What is the minimum circuit operating volt?
232
What is the source voltage in a circuit that consumes 1200 watts at a current of 5 amps
240 volts
Which type of transformer core assembly offers low resistance to magnetic lines of force?
Iron
The type of mounting used for lighting fixtures is indicated in the:
electrical drawings
When terminating the feeders to the main on switchgear, the feeders MUST be braced to withstand:
arc flash energy
The opposition to current flow referred to as:
resistance
What is the name of the connecting device shown in the diagram?
split - bolt
A conductor with 220 mils of insulation would have insulation thickness of:
0.22"
A NEMA type___ enclosure offers only protection against incidental contact
1
Which contact(s) are open when the switch is in the START mode?
1 & 2
What contacts are closed in the RUN mode?
1 & 3
.A current transformer has a rating of 4000: 5 if 1000 amps load is on the primary, the secondary output would produce
1.25 amps
4.What is the voltage drop for a #8 (16.510 cmil) copper wire at 120v. 215 feet one way and a load of 39amps?
10.5
The turns ratio of a 3 phase 13.8kV transformer is 115 to 1. What is the output voltage of the secondary
120 volts
What is the MINIMUM length pull box that can be placed in a 2 inch conduit run where the conductors will be pulled straight..
16 Inches
according to NEC Article 240.4(D) (5),12 AWG copper shall be protected against overcurrent by a device with a MAXIMUM ampacity of.
20 amps
The length of bare copper conductor in a ground ring MUST be buried no less than 2.5' below grade and with a length of at LEAST:
20 ft
A 10 inch offset at 30 degrees is being made what is the distance between center to center bends
20 inches
.What will be the center-to-center measurement for two 30 degree bends in an offset bend with a height of 18 inches?
36 inches*
A Type "X" conduit body has how many conduit entries
4
How many paths for current flow are in a current consisting of 4 resistors in parallel?
4
The NEC requires conduit and fitting installed in hazardous locations to be wrench tight with MINIMUM of how many engaged threads?
4
The NEC allows copper busbars to carry 1000 amps per square inch, if a bus bar measures ¼ inch X 2 inches how many amps is this bar allowed to carry
500
PVC conduit, fittings and connectors range in size from ½ inch to:
6 Inches
Rubber gloves MUST be electrically tested at MAXIMUM intervals of:
6 months
The frequency of a circuit is 15 cycles per ¼ second: What is the Hertz (Hz) rating of the circuit?
60
If a 90 degree stub to be bent is using 10 degree segments, how many bends are required?
9
The device used to prevent moisture from accumulating in hazardous wet locations is called a:
A Drain seal
A swivel joint connection is to be made in a cable tray installation. What Must be installed
A flexible bonding jumper
What is a system of grounding electrodes interconnected by grounding conductors that are buried in the earth to provide lower resistance?
A ground grid
What is the standard size system used in the united states
AWG
Which type of transformer has its windings connected in series?
A wye transformer
An auxiliary holding contact ( seal- in) on a typically NEMA starter is indicated by the terminal marking:
A1 & A2
IEC style contactor coils are marked with the labels of:
A1 & A2
Add a capacitator to increase the power factor
Add a capacitator to increase the power factor
What instrument is used to measure current
Ammeter
Cable markings show all of the following EXCEPT
Ampacity
In the event of an emergency where the lockout/ tagout device is left secured, who can remove the lockout/tagout device?
Authorize supervisor
Which of the following category ratings would a meter need to have to take voltage readings at the service switchgear of an industrial facility?
CAT 111
Which of the following is the classified location where combustible dust is always present?
Class 11 Div 1
What connector should be used to splice a 15 KV shielded cable
Compression
What protects the wires from the sharp edges of the conduit is joined to the metal?
Couplings
A dangerously high voltage is produced when someone opens the secondary circuit of a:
Current transformer
A megger will be used to check an in-service cable. The Electrician MUST be sure that the circuit is:
De-energized and locked tagged out, and tested
The conductors used to connect the system grounded conductor or the equipment to a grounding electrode or to a point on the grounding:
Electrode conductor
The recommended method of attaching self- regulating heating cables to pipes is by using:
Fiberglass tape
For a given number of poles, What determines the speed of an AC motor?
Frequency
All parts of a metal cable tray MUST be bonded together and:
Grounded
Which of the following is not a reason why electrical systems must be grounded?
Limit the potential between ungrounded conductors
What's the MAIN characteristic of a confined space?
Limited access and egress
The AIC Rating of an overcurrent protection device represents its:
MAXIMUM fault current the device will interrupt
What test equipment can be used to test the condition of insulation in electrical apparatus?
Megohmmeter
The outer covering on a liquid - tight flexible metal conduit is used for
Moisture seal
THE transformer coils of the primary and secondary share NO electrical connection, but current flows through them due to:
Mutual induction
Various MINIMUM requirements have been set forth pertaining to overcurrent devices by the
NEC
The equipment grounding conductor is used to interconnect and bond:
Non- current- carrying metal parts
What is insulating tape?
Non-Conductive adhesive tape
Which symbol represents the overload relay in the schematic diagram?
OL
Which choice best describes the two types of pushbutton operators typically used in motor controls
Open and Closed
The ungrounded conductor of a 240/120 three phase Delta 4 wire system that has the higher voltage to ground MUST be identified with the color:
Orange
Which of the following BEST describes where the type and size of overcurrent protection is found?
Panelboard schedule
Verifying the presence or absence of voltage should be performed only by:
Qualified Individuals
The opposing force to a flow of alternating current is called:
Reactance
According to the NEC, where is the "C" phase system to be located ( viewing from the front) with respect to the A and switchboard?
Right
What type of bend is used to change conduit elevation to clear an obstruction and then return to the original eleva
Saddle
Materials made of copper or silver are considered
Semi- conductors
The conducting connection, wheather intentional or accidental between any of an electrical system is a:
Short circuit
What should be done to change rotation of a 3 phase motor?
Swap any two T leads
Which type of conductor is approved for installation in a wet location?
THHW
That is a trapeze type support
Two threaded rods supporting a channel or strut
When is it required that conductors be derated?
When there are four or more current- carrying conductors in a conduit
A drawing showing a point A to point B hookup of conductors is called a:
Wiring diagram
Before using a multimeter to check voltage on a breaker you should:
check the meter with a known power source
An electrician reporting to the work area notices that the temporary wiring has been damaged. What should the electrician do?
immediately report it to the supervisors
Horsepower ratings given to electric motors are related to the motors power
input
What two purposes do measuring tape in conduit serve?
it can spread a uniform film of pulling compound inside the conduit and provide an accurate measure
When climbing a ladder ALWAYS face the ladder and:
maintain three-point contact when climbing
the resistor alloy- heating element used in power- limiting heating cables has a:
positive temperature coefficient
Which plan indicates the location of structures and equipment on a property
site
A reduction in capacitance of a capacitator- start motor results in reduce
speed
Percent slip of an induction motor refers to the
the ratio of synchronous speed to rotor speed to rotor speed of the motor
Generally , the most ideal conductor is made of:
copper
What is shown on a sectional drawing?
cutaway view of a building
What is the total resistance of a circuit that has aa 50- chm resistor, a 75- ohm resistor, and a 100- chm resistor in series?
225 ohms
A NEMA type___ enclosure is both watertight and corrosion- resistant.
4X
Which of the following inscriptions on a circuit breaker indicates that the circuit breaker is designed for use on both copper and aluminum wire?
AL/ CU
Which of these is used as a guide to assist cables entering a conduit?
Piston
