CWEA E/I Level 3 With Complete Solutions.

CWEA E/I Level 3 With Complete Solutions. If the potential difference across the coil is low, the coil will: A-draw too much current B-become too hot C-Produce too much magnetic force D-not heat up D-not heat up The NEC identifies environments that contain flammable vapors and gases as which class of hazardous location? A-Class I B-Class II C-Class III D-Class IV A-Class I Which of the following reduces high voltages and currents to save values for measurements? A-auto transformer B-megohmmeter C-instrument transformer D-variable transformer C-instrument transformer In a three wire control circuit, when a power failure occurs: A-The interlock contact will close the circuit B-The operator can restart the meter automatically C-The motor can restart unexpectedly D-The operator must restart the meter manually D-The operator must restart the meter manually Push buttons are classified as standard duty or heavy duty according to the: A-Kind of enclosure B-Service conditions C-frequency operation D-Current carrying ability D-Current carrying ability He push to test pilot light is used in applications where the pilot light is: A-rarely needed B-A neon bulb C-used in DC applications D-in constant use A-rarely needed The advantage of LCDs over LEDs is: A-accuracy B-better visibility C-lower power consumption D-sensitivity C-lower power consumption Shielding protects an analog meter from: a. damage due to careless handling. b. harmful UV rays. c. over-current and surges. d. stray magnetic fields. d. stray magnetic fields. An ammeter should be connected: a. across the line. b. around an inductor. c. in parallel with the load. d. in series with the load. d. in series with the load. Bar graphs and wave forms can be displayed on a LCD screen when the multimeter has: a. analog/digital circuits. b. microprocessor circuitry. c. opposing coils and a commutator. d. parallel ports. b. microprocessor circuitry. The difference between the squirrel-cage rotor and the wound rotor is in: a. their pole-phase groups. b. how the conductors are connected. c. how the current is induced in the conductors. d. all of the above. b. how the conductors are connected. The frame, the core, the winding, and the end plates are all parts of the: a. rotor. b. stator. c. alternator. d. induction motor b. stator. Which of the following is a sign of overheating rotor bars? a. Reduced starting torque. b. Noise. c. Discoloration. d. All of the above. c. Discoloration. Two sources of power, one AC and one DC, are required for running a(n): a. induction motor. b. squirrel-cage motor. c. synchronous motor. d. wound-rotor motor. c. synchronous motor. Modern synchronous motors have: a. both brushes and slip rings. b. brushes, but no slip rings. c. slip rings, but no brushes. d. neither brushes nor slip rings. d. neither brushes nor slip rings. All the following are true of 240-volt systems compared to 480-volt systems, except: a. they cost more to operate. b. they require more current per unit of power. c. they require smaller circuit breakers. d. they are safer. c. they require smaller circuit breakers. If a charged capacitor is removed from a circuit, the capacitor: a. retains its charge. b. loses some of its charge. c. loses most of its charge. d. loses all of its charge. a. retains its charge. Control systems are usually designed so that each individual circuit controls: a. all functions of the machine. b. at least two functions. c. only one function. d. only one device. c. only one function. A 115-volt, 2-KVA, single-phase generator operating at full load will deliver how many amperes? a. 0.23 b. 17.4 c. 57.5 d. 230 b. 17.4 What is the current when a circuit has a 1,500- watt load and a power factor of 86%, and operates from a three-phase 230-volt source? a. 9.7 amps b. 6.5 amps c. 4.4 amps d. 3.8 amps c. 4.4 amps What is the amp-load of a three-phase, 0.5-hp, 230-volt motor with an efficiency rating of 92% and a power factor of 80%? a. 1.27 amps b. 1.19 amps c. 2.55 amps c. 4.41 amps