The electrical NCCER test Which Article of the NEC covers grounding? - answer article 250 Which of the following is a 90-degree, explosion proof fitting? - answer GUAL What is a dropout plate? - answer Metal plate with a curved surface for cable to follow as it passes from the tray
All of the following are common service voltages in the United States EXCEPT: -
answer 372/575 3-PHASE, 4-WIRE What does a GFCI breaker do? - answer Opens a circuit to prevent operation of an electrical device What will happen when one or more coils in a winding are grounded? - answer The motor will automatically blow fuses Eight incandescent lighting fixtures are to be installed. Each fixture is 120- volts, with a 200-watt lamp. What is the total connected load? - answer 13.3 amps The must be grounded in a bussed gutter if used as the main service equipment. - answer Neutral busbar When wall mounting cable tray, ensure that - answer 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 - answer To keep moisture from creeping in The outer covering on liguid-tight flexible metal conduit is used for - answer A moisture seal A good electrical connection should - answer Be mechanically and electrically secure The symbol normally used for duplex - answer Circle with two parallel lines drawb through it Disconnecting means are covered in - answer NEC Section 110-22 1 / 3
In relation to switches, the term throw refers to the - answer Number of internal operations that a switch can perform A 3-phase, 4-wire, 480v service requires ______ current transformer(s) - answer 3 Services conductors and equipment are covered in - answer NEC Article 230 The NEC required that all receptacles installed on 25 amp and 20 amp branch circuits be ______ receptacles - answer Grounding A transformer with the primary of 400 turns and a secondary of 300 turns has a _____ -
answer Step-down turns ratio of 4:3
The circular mil is based on the - answer Cross-sectional area of the wire Of the termination classes listed below, ____ is the only one that provides a seal against external elements. - answer Class 1 Unless otherwise noted. the calculations in AC circuits _____ values. - answer Rms When the coil turns are increased the _____ - answer Induced voltage is increased As the temperature surrounding a self-regulating heating cable rises, the ____ - answer Resistance of the polymeric core increases The motor type that has the highest starting torque is the ____ motor. - answer Capacitor-start For a given number of poles, the ____ determines the speed of an AC motor. - answer Frequency Both induction and synchronous motors operate on the principle of a rotating ____ field
- answer 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: - answer 90Volts The output capacity of a motor is rated in - answer Horsepower The synchronous speed at which a pole, 60 Hz induction motor operates is rpm. - answer 1,800 The sine of 0 degree is - answer 0 Meters used in AC circuits indicate the - answer Effective 2 / 3
The component labeled 7 in figure 1 is a(n) - answer End seal In an AC circuit containing resistance only _____ will flow if the resistance is 10 ohms and the voltage is 120V. - answer 12A The _____ rotor types are generally rugged. - answer Squirrel cage Proofs tests are made at_ of the original factory voltage. - answer 60% Which type of heating cable cannot be cut and terminated in the field? - answer Mineral insulated The secondary of a CT under load should not be opened because of_. - answer Induced high voltage In a transformer ______ - answer Electromagnetic Induction Ocurs When a ground rod is installed, the top of the rod must be positioned ______ grade. - answer Flush with or below When making offset bends, the two kicks must be made perfectly parallel or the resulting offset will have a _____ - answer Crooked Bend conduit that requires a 90 degree change in direction, except 42.All of the following types of condulet may be used as a pulling point for _____ - answer C To be effective, a grounding system must limit the voltage on the electrical system and protect it from all of the following, except _____ - answer Undervoltage conditions What is the MOST common service used in a temporary power panel? - answer 120/240 volt, 1-phase, 3-wire What are the 2 MOST common types of overcurrent protective devices? - answer Circuit breakers and fuses What instrument is used to perform an insulation-resistance test on a 480- volt motor winding? - answer Megohmmeter Why is a seal installed in a run of conduit in a Class I location? - answer Prevent the passage of explosive gases in the conduit Which of the following is the correct formula for OHM's law? - answer I=E/R Which of the following testing instruments operated on the current transformer principle? - answer Clamp-on ammeter
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