Generator Overcurrent Protection Quiz

According to Article 440, how should motor-compressors be protected against overload and failure to start?

What is the maximum percentage at which the separate overload relay should trip for motor-compressors?

Which devices are permitted to serve as the branch-circuit short-circuit and ground-fault protective device for motor-compressors?

Which standard defines a stationary unit (generator) as 'an engine generator that is intended to be hard-wired and/or permanently installed'?

Which type of generator must be marked with their reactances using the correct industry terms?

Which article covers the installation and other requirements for generators?

Which standard provides information on the location of generators?

According to the text, what is the purpose of compliance with 445.18(A)?

What is the requirement for the means of shutdown of the prime mover according to the text?

According to the text, what is the purpose of disabling all prime mover start control circuits?

According to the text, what type of room air conditioners does Part VII apply to?

According to the text, how should the enclosures of room air conditioners be connected?

According to the text, what is the maximum length of a flexible cord used to supply a room air conditioner rated 120 volts?

According to the text, what type of protection device should single-phase cord- and plug-connected room air conditioners be provided with?

Which type of generators are being manufactured with inverter-based designs?

What is the minimum ampacity of the conductors from the generator output terminals to the first distribution device(s) containing overcurrent protection?

What type of overcurrent protection is required for two-wire, dc generators?

What is the ampacity requirement for neutral conductors of dc generators that must carry ground-fault currents?

Which of the following is true about conductors supplied from the generator output terminals?

Under what conditions are tapped conductors permitted from the load side of the protected terminals of a generator set equipped with overcurrent protection?

For which type of generators are tapped conductors not permitted?

What provides short-circuit protection for the tap conductors in a generator equipped with a listed branch-circuit overcurrent protective device or a combination of a current transformer and overcurrent relay?

Which of the following devices can be used for overload protection for motor-compressors and equipment on 15- and 20-ampere, single-phase, branch circuits?

What is the maximum continuous current that a thermal protector applied in accordance with 440.52(A)(2) should permit?

What type of protection should be provided for motor-compressors and equipment used on 15- or 20-ampere 120-volt, or 15-ampere 208- or 240-volt, single-phase branch circuits?

What is the maximum rating for the attachment plug and receptacle or cord connector for motor-compressors and equipment that are cord- and attachment-plug-connected and used on 15- or 20-ampere 120-volt, or 15-ampere 208- or 240-volt, single-phase branch circuits?

According to the text, what is the purpose of the emergency engine shutdown device?

Which of the following is true about the engine shutdown device used as a disconnecting means?

When is the engine shutdown device not required to be a locking-type device?

Which of the following is NOT a reason why an overcurrent device should not be installed in series with the shunt winding of an autotransformer between Points A and B?

What is the purpose of the 2-pole disconnect switch with overcurrent devices OC-1a and OC-1b in the exhibit?

Why is it not permitted to have an overcurrent device located in series with the shunt winding and the overcurrent device in an autotransformer?

According to the text, which type of generators are required to have a remote emergency stop switch?

What is the purpose of requiring shutdown of the prime mover for generators greater than 15 kilowatts?

According to the text, where should the emergency shutdown device be located for one- and two-family dwelling units?

What is the requirement for ground-fault circuit-interrupter (GFCI) protection on receptacles of 15-kW or smaller portable generators?

According to Table 450.3(A), what is the maximum rating or setting of overcurrent protection for transformers rated over 1000 volts in supervised locations only?

What is the maximum rating or setting of overcurrent protection for transformers rated over 1000 volts in any location with a secondary rated over 1000 volts and a transformer with 6% impedance?

How many circuit breakers or sets of fuses are permitted for secondary overcurrent protection in transformers rated over 1000 volts?

What is the maximum percentage of the rated secondary current that the sum of the ratings of the circuit breakers for secondary protection in transformers rated over 1000 volts is permitted to exceed?

Which type of transformers are not covered by Article 450?

What is the purpose of the exception to 445.20(A)?

Which sections in Article 240 and Article 245 are referenced in the informational note?

What is the purpose of compliance with Article 450?

According to Table 450.3(B), what is the maximum rating or setting of overcurrent protection for transformers with currents less than 9 amperes?

What is the maximum rating or setting of overcurrent protection for transformers with currents of 9 amperes or more, according to Table 450.3(B)?

Which method of protection requires primary protection only for transformers, according to Table 450.3(B)?

Which method of protection requires secondary side overcurrent protection at not more than 125 or 167 percent, provided the primary side overcurrent protection is not more than 250 percent of the primary side current rating, according to Table 450.3(B)?

Which of the following is true about the primary overcurrent device for a transformer?

In which cases can the secondary circuit conductors of a transformer be protected by overcurrent devices in the primary circuit conductors?

What methods can be used to handle the increased heating effects of nonlinear load currents on a transformer?

For applications rated not more than 1000 volts, nominal, what article covers the overcurrent protection requirements for transformer conductors?

Which of the following is the correct equation to calculate the voltage that would appear across the primary winding of a transformer when the load impedance is very low?

What is the voltage that would appear across the primary winding of a transformer when the load impedance is very low and the supply voltage is 208 volts?

What is the voltage that would appear across the primary winding of a transformer when the load impedance is very low and the supply voltage is 240 volts?

According to 450.14, where should the disconnecting means for transformers (other than Class 2 or Class 3 transformers) be located?

According to 450.21(A), what are the separation requirements for transformers from combustible materials?

According to 300.22(C)(3), in what type of spaces are transformers permitted to be installed?

Which type of protective device must be provided on the secondary side of the network transformers?

What is the purpose of the reverse-current relay in the network protector?

What type of protective device is commonly used to protect the secondary ties in the network system?

What is the grounding requirement for the transformer secondary supplying the grounded secondary tie system?

According to the text, what is the maximum rating or setting of overcurrent protection for transformers rated over 1000 volts in any location with a secondary rated over 1000 volts and a transformer with 6% impedance?

According to the text, what is the maximum rating or setting of overcurrent protection for transformers rated over 1000 volts in supervised locations only?

According to the text, what is the maximum rating or setting of overcurrent protection for transformers with currents less than 9 amperes?

According to the text, what is the maximum percentage of the rated secondary current that the sum of the ratings of the circuit breakers for secondary protection in transformers rated over 1000 volts is permitted to exceed?

Which of the following is true about the installation of grounding autotransformers on the load side of a supply system grounding connection?

What type of transformer is used to create a neutral reference point on a circuit supplied from a grounded system?

In what scenario can a line-to-ground fault in a feeder circuit cause serious damage to a zigzag transformer?

What type of autotransformer is used to create a 3-phase, 4-wire distribution system from a 3-phase, 3-wire ungrounded system?

According to the text, what is the purpose of compliance with IEEE C57.12.00-2015 and IEEE C57.12.01-2020?

According to the text, what is the purpose of marking the required clearances on the transformer?

According to the text, what is the purpose of bonding the terminal bar to the enclosure in a dry-type transformer?

According to the text, when are dry-type transformers 1000 volts or less located in the open not required to be readily accessible?

According to Article 450, what is the ampacity requirement for the tie circuit if loads are connected at the transformer supply points at each end of the tie and overcurrent protection is not provided in accordance with Parts I, II, and VIII of Article 240?

What is the ampacity requirement for the tie circuit if load is connected to the tie at any point between transformer supply points and overcurrent protection is not provided in accordance with Parts I, II, and VIII of Article 240?

Under what conditions should the conductors of each phase or neutral comply with 450.6(A)(4)(a) or (A)(4)(b)?

What is the requirement for the means of interconnection for the conductors of each phase or neutral in a tie circuit that is not interconnected?

According to the text, what is the minimum separation required for dry-type transformers rated 1121⁄2 kVA or less from combustible material when installed indoors?

According to the text, what is the minimum fire rating required for the transformer room for individual dry-type transformers rated over 1121⁄2 kVA?

According to the text, which type of transformers are exempted from the requirement of being installed in a transformer room?

According to the text, what is the minimum insulation system rating required for dry-type transformers to be exempt from installation in transformer rooms or vaults?

According to the text, what is the maximum primary voltage allowed for dry-type transformers to be commonly used indoors?

According to the text, what is the minimum separation required for dry-type transformers rated 112½ kilovolt-amperes or less from combustible material?

According to the text, what is the maximum distance allowed between dry-type transformers exceeding 112½ kVA and combustible materials of buildings, if the transformers have Class 155 insulation systems or higher and are completely enclosed except for ventilating openings?

Which type of transformers have the greatest need for passive protection to prevent the spread of burning oil to other combustible materials?

What is the minimum fire resistance requirement for the walls and roofs of transformer vaults?

What is the minimum thickness requirement for the concrete floors of transformer vaults in contact with the earth?

What is the minimum height requirement for the door sill or curb of a transformer vault?

According to the text, what is the maximum number of parts per million PCBs that classifies a transformer as a PCB transformer?

According to the text, what is the maximum total capacity of oil-insulated transformers that are permitted to be installed in a vault constructed of reinforced concrete?

According to the text, what is the maximum total rating of electric furnace transformers that are permitted to be installed without a vault in a building or room of fire-resistant construction?

According to the text, what is the maximum total rating of a transformer that is permitted to be installed without a vault in a building or room of noncombustible or fire-resistant construction, if it is an integral part of charged-particle-accelerating equipment?

Which of the following information is required to be indicated on the nameplate of each phase converter according to the text?

What is the purpose of sizing single-phase conductors to prevent a voltage drop not exceeding 3 percent from the source of supply to the phase converter according to the text?

According to the text, what is the ampacity requirement for the single-phase supply conductors of a phase converter?

Which type of phase converter does not have any moving parts?

What is the minimum net area required for ventilation openings in a vault ventilated by natural circulation of air?

What is the maximum rating or setting of overcurrent protection for transformers rated over 1000 volts in any location with a secondary rated over 1000 volts and a transformer with 6% impedance?

What is the purpose of installing a drain or other means for carrying off oil or water accumulation in vaults containing more than 100 kVA transformer capacity?

According to the text, what is the purpose of a liquid confinement area in a nonflammable-fluid-insulated transformer?

According to 450.24, what is the requirement for nonflammable-fluid-insulated transformers installed indoors and rated over 35,000 volts?

What is the purpose of a pressure-relief vent in a nonflammable-fluid-insulated transformer?

According to the text, why is a means for absorbing gases generated by arcing necessary in a nonflammable-fluid-insulated transformer?