430

An attachment plug and receptacle may be permitted to serve as a motor controller if the motor is portable and has a maximum rating of ___ hp.

1/3

When a continuous duty motor one horsepower or more, but not marked with a service factor or temperature rise, is protected by a separate overload device, the device shall be selected to trip at no more than ___ percent of the motor nameplate rating.

115

Branch-circuit conductors that supply a single motor used in a continuous duty application shall have an ampacity of not less than ___ of the motor's full-load current rating as determined by 430.6(A)(1).

125%

Several motors, each not exceeding 1 horsepower in rating, shall be permitted on a nominal 120-volt branch circuit protected at not over ___ amperes.

20

Determine the minimum size overload protection required for a 480-volt, 3-phase, 15 hp, continuous duty motor given the following information.* Design B * temperature rise - 40ºC* service factor - 1.12 * actual nameplate rating - 18 amps

20.7 amps

The full-load current of a 25-horsepower, synchronous, 460-volt, 3-phase motor at unity power factor is ___ amperes.

26

Determine the maximum current setting permitted for overload protection for a motor that has a thermal protector integral with the motor, given the following information.* 71/2 hp - wound rotor type * two-phase, 4 wire, AC * 230 volts

29.6 amps

Disregarding exceptions, what is the minimum number of overload units required by the NEC® to protect a 3-phase motor?

3

What size THHN copper transformer secondary conductors will be required to feed a 3-phase, 30 hp, 480-volt motor load? The secondary conductors terminate at a fusible disconnect with 70 amp fuses. The - transformer primary is supplied by a 12,470-volt circuit protected with 10 amp fuses.

4

A 14 AWG THHN copper conductor is used between a motor starter and a remote start/stop station. What is the maximum size circuit breaker permitted for the motor short-circuit ground-fault protection that will also protect the 14 AWG conductor?

45 amp

What is the full load current of a 30 hp, 230-volt, 3-phase, synchronous motor with a 90% power factor?

69.3 amps

Torque motors are rated for operation ___.

at standstill

Any motor application shall be considered at ___ unless the nature of the apparatus it drives is such that the motor will not operate continuously with load under any condition of use.

continuous duty

Where motors are provided with terminal housings, the housings shall be ___ and of substantial construction.I. nonmetallic II. metal

metal

For general motor application, the fuse size for the motor branch circuit must be determined from ___.

NEC tables

The secondary circuits of wound-rotor ac motors, including conductors, controllers, resistors, and so forth, shall be permitted to be protected against overload by the ___.

motor-overload device