CALIFORNIA ELECTRICAL EXAM PREP

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What is the minimum rating for a listed manual motor controller used as a disconnecting means for a stationary motor, 2.0 hp, rated 208 volts, 3-phase? Select one: a. 2.5 hp b. 1.6 hp c. 4.0 hp d. 2.0 hp

430.109(C). For stationary motors rated at 2 HP or less and 300 volts or less, the disconnecting means shall be permitted to be one of the devices specified in (1), (2), or (3): (1) A general-use switch having an ampere rating not less than twice the fullload current rating of the motor (2) On ac circuits, a general-use snap switch suitable only for use on ac (not general-use ac-dc snap switches) where the motor full-load current rating is not more than 80 percent of the ampere rating of the switch. (3) A listed manual motor controller having a horsepower rating not less than the rating of the motor and marked :"Suitable as Motor Disconnect." A manual motor controller must have a rating at least equal to the rating of the motor that it is disconnecting. If the motor is rated for 2.0 hp, the manual motor starter must be rated for at least 2.0 hp. Key Words: Motors/Disconnecting Means 430-IX. The correct answer is: 2.0 hp

What is the required ampere rating of the disconnect for motor circuits rated 1000 volts, nominal, or less? Select one: a. Not less than 115% of the full-load current rating of the motor. b. Not less than the full-load current rating of the motor. c. Not less than 135% of the full-load current rating of the motor. d. Not less than 125% of the full-load current rating of the motor.

430.110(A). The disconnecting means for motor circuits rated 1000 volts, nominal, or less shall have an ampere rating not less than 115% of the full-load current rating of the motor. Key Words: Motors/Disconnecting means. 430-IX. The correct answer is: Not less than 115% of the full-load current rating of the motor.

What is the minimum ampacity for conductors that supply a single motor, rated 208 volts, 3-phase, 10 HP? Select one: a. 38.5 amps. b. 24.2 amps. c. 30.8 amps. d. 46.2 amps.

430.22 Single Motor. Conductors that supply a single motor used in a continuous duty application shall have an ampacity of not less than 125 percent of the motor full-load rating... Use Table 430.250 to select the FLC of the motor. 30.8 amps FLC x125% = 38.5 amps. 430.22(E) Note: Any motor application shall be considered as continuous duty unless the nature of apparatus it drives is such that the motor will not operate continuously with load under any condition of use. Key Words: Motors/Branch Circuits 430-II. The correct answer is: 38.5 amps.

Unless otherwise permitted, what is the minimum size for conductors supplying small motors? Select one: a. 14 AWG. b. 18 AWG. c. 16 AWG. d. 12 AWG.

430.22(G). Conductors for small motors shall not be smaller than 14 AWG unless otherwise permitted in 430.22(G)(1) or (G)(2). Key Words: Motors/Conductors/Continuous duty. 430.22. The correct answer is: 14 AWG.

What is the minimum wire size, THWN cu., that can be used to supply a 240 volts, DC, 7½ HP motor? Assume the following installations conditions: ambient temperature 30ºC(86ºF), not more than 3 current-carrying conductors in a raceway, and terminals are rated for 75ºC. Select one: a. No. 8 THWN b. No. 12 THWN c. No. 10 THWN d. No. 6 THWN

430.22. Table 310.15(B)(16). 29 amps x 125% = 36.25 amps. Select a No. 8 AWG from the Table. Key Words: Motors/Branch Circuits 430-II. The correct answer is: No. 8 THWN

What is the minimum ampacity for conductors that supply a group of two motors, rated 3-phase, 208 volts, 3 HP and 5 HP? Assume the following installations conditions: ambient temperature 30°C(86ºF), not more than 3 current-carrying conductors in a raceway, and terminals are rated for 75ºC. Select one: a. 27.3 amps. b. 31.48 amps. c. 34.13 amps. d. 37.25 amps.

430.24. Conductors supplying several motors, or a motor(s) and other loads(s), shall have an ampacity not less than the sum of each of the following: (1) 125 percent of the full-load current rating of the highest rated motor, as determined by 430.6(A) (2) Sum of the full-load current ratings of all the other motors in the group, as determined by 430.6(A) (3) 100 percent of the noncontinuous non-motor load (4)125 percent of the continuous non-motor load 5 HP, 208 volts, 3-phase motor = 16.7 amps x 125% = 20.875 amps. 3 HP, 208 volts, 3-phase motor = 10.6 amps 20.875 amps + 10.6 amps = 31.475 round to 31.48 amps Key Words: Motors/Conductors/Several Motors 430.24. The correct answer is: 31.48 amps.

For a motor used in a continuous duty application with a marked service factor of 1.15 or greater, rated over 1 hp, what is the maximum percent of the motor full-load current rating that the overload device can be set to trip? Select one: a. 135% b. 125% c. 100% d. 115%

430.32(A)(1). A separate overload device that is responsive to motor current shall be selected to trip or shall be rated at no more than 125% of the motor nameplate full-load current rating for motors with a marked service factor of 1.15 or greater. Key Words: Motors/Continuous duty/Overload protection. 430.32(A). The correct answer is: 125%

Where is the overload device to be located for a cord-and-plug-connected motor or motor-operated appliance? Select one: a. At the motor controller. b. Before the final overcurrent device. c. As an integral part of the motor or appliance. d. Within 12 inches of the attachment plug.

430.42(C). Where individual overload protection is required for a motor or motor-operated appliance that is attached to a branch circuit through an attachment plug and a receptacle or a cord connector, the overload device shall be an integral part of the motor or the appliance. Key Words: Motors/Overload protection. 430-III. The correct answer is: As an integral part of the motor or appliance.

Without applying Exception No. 2, what is the maximum rating or setting of a dual element (Time Delay) fuse for a 460 volt, standard squirrel cage, 3-phase, 25 HP motor? Select one: a. 40 amps. b. 50 amps. c. 35 amps. d. 60 amps.

430.52(C). 25 HP, 460 volts, motor = 34 amps. 34 amps x 175% = 59.5 amps. Exception No. 1 permits selecting next higher standard size overcurrent device listed in 240.6. 60 amps. Key Words: Motors/Overcurrent Protection 430-IV. The correct answer is: 60 amps.

A three-phase 10 HP motor has a nameplate full load amperes value of 26.2 amperes and a full load current of 28 amperes in Table 430.250. In general motor applications, which current value is the motor overload protection based on? Select one: a. 200% of the nameplate value b. the nameplate value c. 125% of the table full load current d. the full load current value from the table

430.6(A)(2) requires motor overload protection to be based on the motor nameplate value. Key Words: Motors/General/430-I The correct answer is: the nameplate value

For stationary motors rated 2 hp or less and 300 volts or less, what type of device is permitted as the controller? Select one: a. A general-use switch having an ampere rating not less than 125% of the full-load current rating of the motor. b. A general-use switch having an ampere rating not less than twice the full-load current rating of the motor. c. A general-use switch having an ampere rating not less than the full-load current rating of the motor. d. A general-use switch having an ampere rating not less than 150% of the full-load current rating of the motor.

430.83(C)(1). For stationary motors rated at 2 hp or less and 300 volts or less, the controller shall be permitted to be a general-use switch having an ampere rating not less than twice the full-load current rating of the motor. Key Words: Controllers/Motor/Ratings. 430.83. The correct answer is: A general-use switch having an ampere rating not less than twice the full-load current rating of the motor.

A continuous rated motor is powering a passenger elevator. The branch circuit conductors are selected based on a percentage of the nameplate current rating of the motor. What is the percentage of full-load current used for the passenger elevator motor? Select one: a. 120 % of nameplate rating. b. 140 % of nameplate rating. c. 110 % of nameplate rating. d. 200 % of nameplate rating.

Table 430.22(E). Conductors used in a short-time, intermittent, periodic, or varying duty application shall have an ampacity of not less than the percentage of the motor nameplate current rating shown in Table 430.22(E). Key Words: Motors/Continuous duty. 430.22. The correct answer is: 140 % of nameplate rating.

An intermittent duty motor with a 30 minute duty cycle is being used for raising and lowering rolls. What percent of the motor nameplate current is the ampacity of the motor conductors based on? Select one: a. 120% b. 110% c. 100% d. 150%

Table 430.22(E). The ampacity of conductors supplying short-time intermittent duty motors is based on the percentages in the table. Key Words: Motors/Intermittent duty/430.22(E). The correct answer is: 150%

What is the full-load current for a 1 hp single-phase motor with a rated voltage of 230 volts? Select one: a. 6.9 amperes b. 7.9 amperes c. 8.8 amperes d. 8.0 amperes

Table 430.248. The values of full-load currents given in Table 430.248 are for motors running at usual speeds and motors with normal torque characteristics. Key Words: Full-load current motors/Single-phase, Table 430.248. The correct answer is: 8.0 amperes

What is the full-load current for a 25 hp three-phase motor with a rated voltage of 460 volts? Select one: a. 34 amperes b. 74.8 amperes c. 27 amperes d. 68 amperes

Table 430.250. The values of full-load currents given in Table 430.250 are typical for motors running at speeds usual for bolted motors and motors with normal torque characteristics. Key Words: Full-load current motors/Three-phase, Table 430.250. The correct answer is: 34 amperes


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