Electrician NCCER In-class activity

Electrician NCCER In-class activity Which article of the NEC covers grounding? - Article 250 What is a dropout plate? - Metal plate with a curve surface for cable to follow as it passes from the tray All of the following are common service voltages in the United States Except: - 372/575 3-Phase, 4-wire What does a GFCI breaker do? - Opens a circuit to prevent operation of an electrical device What will happen when one or more coils in a winding are grounded? - The motor will automatically blow fuses eight incandescent lighting fixtures are to be installed. Each fixture is 120 volts, with a 200-whatt lamp what is the total connected load? - 13.3 Amps The __________must be grounded in a bussed glutter if use as the main service equipmemt - Neutral busbar When wall mounting cable tray, ensure that - The building structure is strong enough to support the tray system The purpose of sealing cable ends when reels of cable are in storage is ______________ - to keep moisture from creeping in The outer covering on liquid-tight flexible metal conduit is use for - A moisture seal 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 110-22 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 4:3 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% Which type of heating cable can not be cut and terminated in the field? - Mineral insulated 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