Partial preview of the text
Download JATC JW TEST QUESTIONS AND ANSWERS and more Exams Electrical Engineering in PDF only on Docsity!
JATC JW TEST QUESTIONS AND ANSWERS
JATC JW TEST QUESTIONS AND ANSWERS The term kemil is used when referring to cables larger than? — Correct Answer-4/0 The is the unit of area used to measure the cross sectional area of wire, — Correct Answer—Cireular mil Conyert 300 microamps to milliamps, — Correct Answer-0.5 ma. SO0OQuAxTmA/1000UA mA If you bought a 2 liter battle of wire lubricant approximately how many pints did you buy. Given 1 pint = .04732 liter — Correct Answer—4 and 1/4 pints. 2Lx1P/.4732I. The most commen method of producing clectricity is through the use of? — Correct Answer- Magnetism The unit of current flow is the? — Correet Answer-Ampere Only can use power in an clectrical circuit. - Correct Answer—Resistance Identify the symbol shown in the figure below -—--o/ o--— — Correct Answer—Normally—open switch Current flow through a circuit is by resistance in the circuit, — Correet Answer Limited If you increase the voltage in a series circuit, the current will? — Correct Answer— Increase Calculate the total power dissipated in a serics circuit supplied by 24 volts with the following laads Given: R1=80hms, R2=4oahms — Correct Answer—48 watts The total resistance of a parallel circuit is the value of the lowest value resistor. — Correct Answer-Less than In a parallel circuit, in which branch is the greatest amount of power consumed. — Correct Answer—Branch of least resistance Which formula below will not help you find the total power in a combination circuit? — Correct Answer—-P=12/R In a three—wire, single-phase system, what is the maximum UNBALANCED load the neutral conductor must be able to carry? — Correct Answer—The full load of cither leg all generators produce voltage. — Correct Answer-AC In a generator, maximum positive voltage is induced at degrees of armature . — Correct rotation and maximum negative yoltage is induced at degre Answer-90 / 270 Alternating current flowing through an inductor is opposed by resistance and? — Correct Answer—Reaclance The minimum size copper grounded conductor for an alternating current service that utilizes 350 kemil copper ungrounded service conductors is ? Assume that the calculated size camplies with the Article 220 requirements. — Correct Answer-Noa, 2 The minimum size aluminum main bonding jumper for an alternating current service n that utilizes three 350 kcmil aluminum, ungrounded service conductors per phase is? — Correet Answer-No. 4/0 A is a device that protects against electric shock by detecting an imbalance of current in the normal conductor pathways and opening the circuit. — Correct Answer— Ground fault circuit interrupler is the amount of harmonics on a linc compared ta the fundamental frequency of 60 Hz. — Correct Answer-Total harmonic distortion Which of the [allowing is NOT a common buck—boosl transformer application? — Correct Answer—Creating a d-phase, 4-wire wye circuit from a $-phase, 3-wire delta circuit. A transformer is a precision two-winding transformer used to step down high yallage la allow sale voltage measurements. — Correct Answer-Po tential Interior metal water piping located more than feet from the paint of entrance to the building shall not be used as part of the grounding electrode system or as a conductor to interconnect electrodes that are part of the grounding clectrade system, — Correct Answer-3 In all grounded systems of 600 volts or less, the maximum current that will flow in the grounding clectrade conductor is limited by the of the circuit. — Correct Answer- Impedance The equipment bonding jumper is permitted to be installed cither inside or outside of a raceway of enclosure. Where the jumper is installed on the outside, the length is generally limited to note more than feel. — Correct Answer-6 Which of the following is not permitted to be used as an equipment grounding conductor? — Correet Answer-rigid non-metallic conduit. The method employed for clearing a short circuit is the same regardless of whether the system is grounded or ungrounded. Essentially, it involyes placing an overcurrent device in series with cach system conductor. — Correct Answer-Ungrounded Which of the following are permitted sources for scparatcly derived systems? — Correcl Answer—A battery, a solar photovoltaic system, a generator The rules in the NEC for grounding at more than one building do NOT require a grounding electrode at the separate building or structure where only ___ branch circuit(S) supply / supplies the building or structure and the branch circuit (s) include(s) and equipment grounding conductor for grounding equipment supplicd by the branch circuil(s) — Correct Answer—One Which of the following locations docs NOT require GICI protection for 125-volts, single-phase 15 and 20-ampere receplacles in other than dwelling unit type occupancies? — Correct Answer—Bathrooms, outdoors, kitchens In North America virtually all power systems opcrate at? — Correct Answer-60 hZ% The reference for analyzing a parallel LCR circuit is the? — Correct Answer Voltage A circuit that offers high opposition to current flow when the frequency is low, but decreases opposition dramatically after the frequency reaches a certain point is called a filler. - Correct Answer-[ligh pass A circuit pulling 8 amperes of current is supplied with 218 volts. a meter in the circuit shows a power factor of 67 percent. Calculale the true power [or the circuit. — Correct Answer-1168.9w Papp=lixI, Ptrue=Pappx0.67 poor power factor caused by motor loads can be corrected by placing? — Correct Answer-Capacitors in parallel with the motors. The DISTANCE an clectromagnetic wave or signal can trayel during one cycle of alternating yolrage is known as the? — Correct Answer—Wavelength Three—phase power is generated by rotating a magnetic field through three sets of coils arranged degrees apart. — Correet Answer-120 A generator produces maximum yoltage at degrees and degrees of rotation, — Correct Answer-90 / 270 The type of voltage that represents an equivalent DC voltage in an AC system is the vollage — Correct Answer-RMS (effective) What is the inductive reactance of a coil with an inductance of 600 millihenrics when connected to a 10 kiloherts supply? — Correet Answer-37.7 kilo ohms X1=2pieP]L.=2x3.14x10,000x0.6=37,6800hms Solenoid use laminated iron construction lo reduce? — Correct Answer—Eddy currents The requires motor controllers to disconnect electrical power to the motor and provide protection from overload condition, — Correct Answer—Nation [lectrical Code The operational life or standard life expectancy of a rclay is known as its? — Correct Answer—Duty rating An industrial relay that contains reversible contact cartridges can casily be changed from (NC) to (NO) by the contact blacks. — Correct Answer—Rolating What type of visual indicator would decrease the amount of time required to troubleshaot a lamp? — Correet Answer—Push-to-test pilot light Replacing manual aperating devices with automatic controls will normally allow a process to be operated more and efficiently. — Correct Answer-Economically, simply, safely A is NOT a basic temperature device — Correet Answer—Mercury bulb switch Ladder diagrams illustrate the of all electrical components in the circuit — Correct Answer-Electrical relationship are the mast common type of aver current protection device used in motor control circuit applications, — Correct Answer-luses Identify the transformer connection below. — Correct Answer-Pri. wye low valt / sec. wye low volt What is the turn ratio of a transformer with a primary current of 31 amps anda secondary full load current of 62 amps? — Correct Answer 2:1 Poor power factor is normally caused by loads on the service which results in the line current lagging the voltage. — Correct Answer-Inductive The windings of a transformer are connected to the source yoltage. — Correct Answer-Primary In purely inductive circuits, the current the applied voltage by 90 degrees. — Correct Answer-Lags If the frequency is increased in a series RL circuit, the current will 2 — Correct Answer—Decrease A serics circuit has an extremely large Xe and an extremely small R. The power factor will be close to percent. — Correct Answer-O0 
