Review questions: (keyword: motors), (keyword: motors<%>)

Réussis tes devoirs et examens dès maintenant avec Quizwiz!

65V

Generators operating at ___________ or less and driven by individual motors shall be considered as protected by the overcurrent device protecting the motor

1/3

Motor-starter rheostats for DC motor operated from a constant voltage supply before the speed of the motor falls to ___________ its normal value

190%

DC motors operating from a rectifier bridge of the single-phase half-wave power supply, the conductors between the field wiring terminals of the rectifiers and the motor shall have an ampacity of not less than 190% of the motor full-load current rating

115%

Disconnecting means to a torque motor shall have an ampere rating of at least ___________ of the motor nameplate current

150V

The frames of portable motors that operate over ___________ to ground shall be guarded or grounded

72%

For wye-star delta-run motor the ampacity of the conductors between the controller and the motor shall not be less than ___________ of the motor full load current rating

125%

Conductors that supply a single motor used in a continuous duty application shall have an ampacity of not less than ___________ of the motor full load current rating

60A

A 3.5 mm^2 conductors which extend beyond a motor control equipment enclosure shall be permitted to be protected by the motor branch-circuit protective device if its rating is not more than ___________

143A

A 50 hp 208V, three-phase squirrel cage motor has a full-load current of ___________

2hp

A general-use switch rated at twice the full-load current shall be permitted as a disconnecting means for stationary motors rated at ___________ or less.

125%

Branch circuit conductors supplying a single motor compressor shall have an ampacity of not less than ___________ percent of either the motor compressor rated load current or the branch circuit selection current whichever is greater

125%

Branch circuit conductors supplying a single phase motor shall have an ampacity NOT exceeding ___________

125%, 100%

Conductors supplying a fire pump motor pressure maintenance pumps and associated fire pumps accessory equipment shall have a rating not less than ___________ of the sum of the fire pump motor and___________ of the associated fire pump

125%

Conductors supplying several motors shall have an ampacity not less than ___________ of the full load current rating of the highest rated motor plus the sum of the full load current rating of all other motors

25%

Conductors supplying two or more motors shall have an ampacity equal to the sum of the full-load current rating of all the motors plus ___________ of the highest rated motor in the group

25%

Conductors supplying two or more motors shall have an ampacity not less than the sum of the rated currents of the motor plus ___________ of the highest motor full load current in the group

50V

Exposed live parts of motors and controller operating at ___________ or more between terminals shall be guarded against accidental contact by enclosure

150%

For AC adjustable voltage, variable torque drive motors, the ampacity of conductors, or ampere ratings of switches, circuit breakers or fuses and ground fault protection shall be based on the operating current marked on the nameplate. If the current does not appear on the nameplate, the ampacity determination shall be based on 150% of the values given in tables

125%

For DC motors operating from a rectified power supply the conductor ampacity on the input of the rectifier shall not be less than ___________ of the rated input current to the rectifier

125%

For continuous duty the conductors connecting the secondary of a wound rotor AC motor to its controller shall have an ampacity not less than ___________ of the full load secondary current of the motor

15m

For motor starter to be in sight of the controlled motor, it must NOT be more than ___________ away

125%

For motors with a marked service factor of 1.15 or greater the overload device shall be selected to trip at ___________ percent of the motor nameplate full load current rating

125%

For motors with marked temperature rise of 40C or less the overload device shall be trip to ___________ of the motor nameplate full load current rating

115%

For motors with no marked service factor and no marked temperature rise the overload device shall be selected to trip at ___________ of the motor nameplated full load current rating

130%

For motors with no marked service factor and no marked temperature rise where the overload is not sufficient to start the motor or carry the load the maximum setting can be permitted to ___________

125%

For multispeed motor the ampacity of the conductors between the controller and the motor shall not be less than ___________ of the current of the windings that the conductors energize

62.5%

For part winding motor the ampacity of the conductors between the controller and the motor shall not be less than ___________ of the motor full load current rating

125%

For wye delta run connected motor the ampacity of the branch circuit conductors on the lied side of the controller shall not be less than ___________ of the motor full load current

140%

Motors with a marked temperature of 40°C or less where the overload is not sufficient to start the motor or carry the load the maximum setting can be permitted to 140 percent

140%

Motors with marked temperature rise not over 40 degrees Celsius shall have an overload protection equal to ___________ of the motor full load current

20A

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

115%

The ampere rating of hermetic refrigerant motor-compressor shall be at least ___________ of the nameplate rated-load current

70% to 90%

The centrifugal switch will disconnect the auxiliary winding of the motor at about ___________ of synchronous speed

115%

The disconnecting means for motors circuits rated 1000v nominal or less, shall have an ampere rating of ___________ of the motor full load current

115%

The disconnecting means for motors circuits rated 1000v nominal or less, shall have an ampere rating of ___________ the motor full load current

115%

The disconnecting means serving a hermetic refrigerant motor-compressor shall be selected on the basis of the nameplate rated-load current or branch circuit selection current of the motor compressor. The ampere rating shall be at least ___________ of the nameplate rated-load current

115%

The minimum size disconnecting means allowed for a hermetic refrigerant motor-compressor is ___________ of its nameplate rated-load current

175%

The motor compressor branch circuit short circuit and ground fault protective device shall be capable of carrying the starting current of the motor the protective device shall be rate not exceeding 175 percent of its rated load current

15%

The voltage at the fire pump controller line terminals shall not drop more than ___________ below rated voltage under motor stating conditions

5%

The voltage at the load terminals of the fire pump controller shall not drop more than ___________ below the voltage rating of the motor when the motor is operating at 115 percent of its full load current rating

115%

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

60A

When only one receptacle for non-motorized equipment is installed on an individual branch circuit within 30 ampere rating the receptacle shall have a current rating of ___________

15A

Where a motor is connected to a branch circuit by means of an attachment plug and a receptacle or a cord connector the rating of the attachment plugs and receptacle or cord connector shall not exceed ___________ at 125 volts or 250 volts

3

he minimum number of overload units such as heaters, trip coils, or thermal cutouts allowed for a three- phase AC motor protection is ___________


Ensembles d'études connexes

Topic 3 - the South Korea and Taiwanese political economy since 1945

View Set