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Electrician NCCER With 354
Questions With Answers
The standard unit for measuring the cross-sectional are of a wire is? - ✔ ✔ Circular mil A conduit bending Hickey can be used to bend conduit from - ✔ ✔ 0-15 degrees When should a de-oxide compound be used? - ✔ ✔ During an aluminum-copper connection When should a de-oxide compound be used? - ✔ ✔ During an aluminum-copper connection All of the following information is found on a one-line diagram of a substation EXCEPT - ✔ ✔ The scale What instrument is used to measure current? - ✔ ✔ Ammeter What are the 3 elements in every electrical circuit? - ✔ ✔ Power source, wire, and load What are the two most commonly used methods of terminating grounding? - ✔ ✔ Exothermic (caldwelding) and mechanical Chico sealing compound is to be applied in an EYD fitting, the electrician must make sure that? - ✔ ✔ The drain remains clear The point of attachment of service drop conductors must provide minimum clearance as specified in what NEC table? - ✔ ✔ 230-
Which Off The following componentes is part of A DUAL ELEMENT FUSE? - ✔ ✔ Time delay A holding contact in a motor starter normally connected in parallel with? - ✔ ✔ The starter push bottom The potential across the circuit is 480 volts and the current is 50 amps, what is the resistance of the circuit? - ✔ ✔ 9.6 ohms Normally you should need all of the following in a wire pull operation EXCEPT? - ✔ ✔ Scaffolding The color of the outer finish required to mark a phase busbar or the conductor having the higher voltage to ground is? - ✔ ✔ Orange The type and sized of overcurrent protection may be found in the - ✔ ✔ Panelboard schedule After a hazard review is completed, __________ determine(s) the classification of a confined space as a nonpermit or permit- required confined space - ✔ ✔ The supervisor and project/safety managers When de busbars are secured to withstand the torque created by the available amount of short circuit current, they are said to be? - ✔ ✔ Braced It is not a good idea to use needle- nose pliers to bend wire in preparation for a termination because? - ✔ ✔ Gripping the conductor and bending it with needle-nose pliers can scar or weaken the conductor
To strip insulation when splicing wire, _________ should be used. - ✔ ✔ Wire strippers Two clevis types are_______ - ✔ ✔ Straight and swivel The voltage drop of conductors carrying alternating current in PVC will be _______ that of identical conductors in metal conduit. - ✔ ✔ Less than Keyed interlocks (kirklocks) may be? - ✔ ✔ Use to control equipment operation sequences The least desirable method of exiting cable from a cable tray is? - ✔ ✔ From the end of the tray without a dropout plate The best device for transporting very large cable reels is a? - ✔ ✔ Cable reel transporter A(n) _____operates on the same principle as a current transformer. - ✔ ✔ Clamp-on ammeter The type of drawing that shows the general arrangement of service entrance equipment and panelboards, along with the related services and feeder conduit/conductor, is a? - ✔ ✔ Power-riser diagram The type of fitting used to suspend cables in long vertical runs of cable tray is a? - ✔ ✔ Cable hanger elbow The UL label on a device means the device - ✔ ✔ Has undergone testing at a nationally-recognized testing laboratory and meets the minimum safety requirements
When working on deenergized circuits that have capacitors installed, the first thing that should be done is to? - ✔ ✔ Short out all parts of the circuit with a shorting prove and leave the probe connected to the circuit Cable splice are allowed in cable tray system provided they are? - ✔ ✔ Made and insulated by NEC approved methods The primary advantage of using recording instruments is that they? - ✔ ✔ Can be connected to take and record continuos measurements The number of wraps on the _______decides the amount of force applied to the pull - ✔ ✔ Puller drum (capstan) A DC ammeter is connected? - ✔ ✔ In series with the circuit The maximum pull that should be exerted on cables being pulled in tray when using a basket grip is ______ pounds - ✔ ✔ 1, Where is nonmetallic conduit (pvc) used? - ✔ ✔ Both above and below ground Which of the following conductors has the lease resistance? - ✔ ✔ 1/0 awg What instrument is used to measure current? - ✔ ✔ Ammeter What is used to make a slight change in elevation in a cable tray system? - ✔ ✔ Swivel plates Pvc, conduit, fitting, and connectors range from 1/2" to - ✔ ✔ 6 inches
The secondary of a CT under load should not be opened because of______ - ✔ ✔ Induced hight voltage In a transformer,______ - ✔ ✔ Electromagnetic induction occurs When a ground rod is installed, the top of the rod must be positioned _____.grade - ✔ ✔ Flush with or below When making offset bends, the two kicks must be made perfectly parallel or the resulting offset will have a ________ - ✔ ✔ Crooked bend All of the following types of condulet may be used as a pulling point for conduit that requires a 90 degree change in direction, except_______ - ✔ ✔ C To be effective, a grounding system must limit the voltage on the electrical system and protect it from all of the following, except ______
- ✔ ✔ Undervoltage conditions What is the most common service use in a temporary power panel? - ✔ ✔ 120/240 volt, 1-phase, 3-wire What are the 2 most common types of overcurrent protective devices?
- ✔ ✔ Circuit breakers and fuses What instrument is use to perform an insulation resistance test on a 480 volt motor winding? - ✔ ✔ Megohmmeter What is a seal installed in a run of conduit in a class I location? - ✔ ✔ Prevent the passage of explosive gases in the conduit
Which of the following is the correct formula for OHM's law? - ✔ ✔ I=E/R Which of the following testing instruments operated on the current transformer principle - ✔ ✔ Clamp-on ammeter A drowning showing a point A to point B hookup of conductors is called a - ✔ ✔ Wiring diagram What does HOA usually mean in a motor control circuit - ✔ ✔ Hands of automatic A120/208 Volt feeder consist of an 800 ft run of 500 kcmil aluminum wire in conduit. This feeder has 5% voltage drop. What will the phase- toPhase voltage be at the load end - ✔ ✔ 197.60 volts What is voltage? - ✔ ✔ electromotive force What is the standard wire size system used in the United States? - ✔ ✔ AWG A switch labeled "AL-CU" can be use with what type of wire? - ✔ ✔ Aluminum Copper and copper clad aluminum What type of conduit fitting is usually placed in the middle of a long run of rigid metal conduit to provide access for pulling wire - ✔ ✔ C What is the largest size of aluminum rigid conduit couplings? - ✔ ✔ 6" What is the purpose of the thermocouple? - ✔ ✔ To measure temperature
What maximum number of bends is allowed between fittings in one conduit run? - ✔ ✔ 4 quarter bends or 360 degrees What size wire is standard for a 120-volt motor control systems? - ✔ ✔ # In all cases where live parts are normally exposed on the front of switchboards or motor control centers the working space in front of such equipment must be what minimum length? - ✔ ✔ 3 FT What is the interrupting rating of a fuse - ✔ ✔ The maximum value off current that the fuse is designed to interrupt. What is the symbol for the primary side of a transformer? - ✔ ✔ H An electrical fitting can be made explosion proof in which of the following ways? - ✔ ✔ Using an amorphous sealed device A megger will be used to check a cable. The electrician must be sure that the circuit is - ✔ ✔ De-energized and locked, tagged out, and tested What is the function of a ballast on a fluorescent fixture? - ✔ ✔ Steps up the voltage What is the primary purpose of P&ID - ✔ ✔ Provide scale drawings and piping and instrumentation control systems. Which of the following factors is used to control the speed of an induction motor? - ✔ ✔ Frequency A 10-inch offset at 30 degrees is been made. What is the distance between center-to-center bends? - ✔ ✔ 20 inches
What is an acceptable protection techniques for electrical equipment in hazardous location? - ✔ ✔ Use duct-ignition proof equipment What is the purpose of lockout/Tagout? - ✔ ✔ Prevent operation What test or equipment can be use to locate suspected short circuit in 1 phase of a 3 phase motor? - ✔ ✔ Megger A 1 line diagram with simplified symbols indicates the - ✔ ✔ Interconnections and component parts of an electrical circuit What will happen if moisture is inside a cad-weld mold while the weld is being performed? - ✔ ✔ The cadwel mold could explode What is produced in a conduit run by making 2 equal bends in opposite direction? - ✔ ✔ Offset Cable trays are usually supported by all of the following means except?
- ✔ ✔ #9 wire 4-inch square boxes are available with all of the following depths except? - ✔ ✔ 1 inch What is installed at a expansion joint to provide a continuous ground between 2 sections of cable tray? - ✔ ✔ A bonding jumper What color identifies and insulated, grounded, number 4 conductors? - ✔ ✔ Green What is it important to torque bolts when busbars are connected? - ✔ ✔ Decrease resistance on the connection All of the following are protective devices for motors except - ✔ ✔ Solenoid
What are the 3 elements in every electrical circuit? - ✔ ✔ Power source, switch, and load What are the 2 MOST commonly used methods of terminating grounding? - ✔ ✔ Exothermic (Cadwelding) and mechanical How should power cable and signal cable be placed in the same cable tray? - ✔ ✔ Place a divider between the signal cables and the power cable The point of attachment of service drop conductors MUST provide MINIMUM clearances as specified in what NEC Cable? - ✔ ✔ 310- The NEC requires that switch, receptacle, and fixture boxes be ________ with the finished face of the wall surface when combustible material, such as ply-wood or paneling, is been used - ✔ ✔ Mounted flush A voltage of 1 volt applied across a resistance of 1 ohm produces a current of 1 amp. If the voltage is double and the resistance is halved, then the current _______. - ✔ ✔ Increases 4 times The force that causes electrons to flow is most commonly called _________. - ✔ ✔ Voltage Copper is the most widely used conductors because it _________. - ✔ ✔ Offers low resistance and is easy to use The installation specifications of both surface metal raceways and surface nonmetallic raceways can be found in________. - ✔ ✔ NEC Articles 352
A dropout plate is best describes as a ______. - ✔ ✔ Plate with a curved surface for cable to follow as it passes from the tray The 2 basic cable tray failures under load are ________. Failures. - ✔ ✔ Side rail and rung What is the correct combination for hooking up a 480-volt motor with 9 leads - ✔ ✔ L1&T1, L2&T2, L3&T3, 4&7, 5&8, 6& What should be used on every wire pull through conduit - ✔ ✔ Wire lube When should a de-oxide compound be used - ✔ ✔ During an aluminum to copper connection Given: the distance between a starter and a 3 phase motor is 73 ft. The starter MUST have a 5 ft tail and the motor a 3 ft tail. How much multi- conductor wire is REQUIRED for a pull from the starter to the motor? - ✔ ✔ 81ft To properly install a compression lug on a conductor requiring multiple crimps, the electrician will crimp? - ✔ ✔ Starting from the lug eye to the barrel opening All of the following are standard fuse sizes except - ✔ ✔ 550 Amp What type of circuit breaker was developed to meet the needs of systems where high potential fault-currents are present? - ✔ ✔ Current-limiting Where are the overload heaters normally located in a motor circuit? - ✔ ✔ In the motor starter Between The "T " leads and the Contactors
The indication provide by a voltage tester represents ________. - ✔ ✔ That there is a potential difference between 2 points A voltmeter is connected in _______ - ✔ ✔ Parallel with the circuit. According to Ohm's law, the amount of current in a circuit is equal to the _______. - ✔ ✔ Voltage divided by the resistance Intermediate metal conduit (IMC) is a type of conduit that - ✔ ✔ Has a wall thickness less than that of rigid metal conduit but thicker than EMT Which of the following is the " heating element " in a self-regulating heat trace? - ✔ ✔ Semiconducting core The voltage of a DC circuit to be measured. How should the meter be connected to ensure proper polarity? - ✔ ✔ The (-) with the (-) and the (+) with the (+) What does a watt meter indicate? - ✔ ✔ True power Electrician metallic tubing must be supported with what maximum distance from each junction or oulet box? - ✔ ✔ 3ft When transporting metal conduit, it is important to - ✔ ✔ Protect the threads keep the caps on to prevent thread damage The voltage drop of conductors carrying AC in PVC conduit will have what relation to that of identical conductors in the conduit - ✔ ✔ The same What type of wire is the standard for low voltage milliamp signal system? - ✔ ✔ Single pair shielded
Cable makings show all of the following, excep - ✔ ✔ Ampacity All of the following are found on an elevation view of a motor control center, except - ✔ ✔ Location of motor The drawing scale is most likely to be found in which of the following drawing location? - ✔ ✔ The drawing title block Receptacles are rated according to the - ✔ ✔ Voltage and amperage capacity What color wire is connected to the silver screw in an incandescent fixture? - ✔ ✔ White What is the NEC requirement for labeling disconnects? - ✔ ✔ All disconnects devices for circuits, feeder and, equipment must be clearly and permanently mark A 3 way switch, is what type of switch - ✔ ✔ SPDT The relationship of a transformer primary winding to the secondary winding is expressed in? - ✔ ✔ Turns ratio The number of complete AC cycles per second is called? - ✔ ✔ Frequency The value indicated on a meter for an AC circuit are defined as root- mean square, what is another term for this? - ✔ ✔ Effective value In a shine wave, the number of times per second an identical pattern itself is known as? - ✔ ✔ Frequency of a waveform What does frame size provide information about? - ✔ ✔ Proper bolt-up
A good electrical connection should - ✔ ✔ Be mechanically and electrically secure The symbol normally use for duplex - ✔ ✔ Circle with two parallel lines draw through it Disconnecting means are covered in - ✔ ✔ NEC section 110- In relation to switches, the term throw refers to the - ✔ ✔ Number of internal operations that switch can perform A 3-phase, 4-wire, 480v service requires ________ current transformers
- ✔ ✔ 3 Services conductors and equipment are covered in - ✔ ✔ NEC Article 230 The NEC required that all receptacles installed on 25 amp and 20 amp branch circuits be__________ receptacles - ✔ ✔ Grounding The circular mil is based on the - ✔ ✔ Cross-sectional area of the wire A transformer with the primary of 400 turns and a secondary of 300 turns has a - ✔ ✔ Step down turns ratio of 4: Of the termination classes listed below,_____ is the only one that provides a seal against external elements - ✔ ✔ Class 1 Unless otherwise noted, the calculations in AC circuits ______ values - ✔ ✔ Rms When the coil turns increased the ________ - ✔ ✔ Induced voltage is increased
As the temperature surrounding a self regulating heating cable rises, the ________ - ✔ ✔ Resistance of the polymeric core increases The motor type that has the highest starting torque is the _________ motor - ✔ ✔ Capacitor - start For a given number of poles, the________ determines the speed of an AC Motor. - ✔ ✔ Frequency Both induction and synchronous motor operate on the principle of the rotating________field - ✔ ✔ Magnetic A Transformer has 200 turns in the primary, 150 turns in the secondary, and 120VAC applied to the primary. The voltage across the secondary is
- ✔ ✔ 90 Volts The output capacity of a motor is rated in - ✔ ✔ Horsepower The synchronous speed at witcha 4 pole, 60 Hz induction motor operates is ________ rpm - ✔ ✔ 1800 The sine of 0 degree is - ✔ ✔ 0 In a AC circuit containing resistance only, _______ 12A will flow if the resistance is 10 ohms and the voltage is 120V - ✔ ✔ 12A The _____ rotor types are generally rugged - ✔ ✔ Squirrel cage The componente labeled 7 in figure 1 is a (an) - ✔ ✔ End seal Meters used in AC circuits indicate the_______ - ✔ ✔ Effective Proofs tests are made at________ oF the original factory voltage - ✔ ✔ 60%
