NETA Level 2

Réussis tes devoirs et examens dès maintenant avec Quizwiz!

NFPA 70 defines work space condition ____ as having live parts on one side and grounded parts on the other side

2

Radial system with primary selectivity

2 feeds feeding switches to choose which feeds the main bus (this can be used with an ATS)

primary selective system

2 primary breakers feed 2 busses connected by a tie breaker that is usually open

Which device functions when the circuit admittance, impedance or reactance increases or decreases beyond predetermined limits?

21 Distance relay

What size cable would you expect to find on ASTM Grade 4 personal protective grounds?

3/0 AWG

How much torque is required to produce 300 HP at 4600 RPM?

343 lb-ft HPx5252/rpm=torque

A given 120VAC 60Hz circuit has a load of 10A with a 20� lagging power factor for 30 minutes. What is the reactive power?

410.42 VAR 120V*10A=1200W*sin(20)=410.42 VARs

Which protective relay functions on a predetermined value of polyphase voltage in the desired phase sequence?

47

Point to point results on new grounding systems in a generating station that exceed ______ should be investigated

500 milliohms

What is the insulation resistance test voltage for emergency generator for windings rated at 480V line to line

500V

A delta-wye transformer has a turns ratio of 9:1. The primary line voltage is 3600 V. What is the secondary line voltage?

692.8 V

What is the NETA-ATS recommended test voltage for hipot testing a 3-phase, 34.5kV automatic circuit recloser with a rated impulse withstand voltage of 150kV?

70kVAC Test Voltage = Operating Voltage*2+1000V VDC = VAC*1.414

The maximum voltage of an industrial multimeter without a high voltage probe is typically

750-1000V RMS - Non Continuous

What is the expected contact-resistance measurement for a 4000A 480V air circuit breaker in good condition?

8-24 microhms

Which of the following would best describe a transformer?

A device that changes voltage and current levels

Which of the following is not a form of respiratory protection defined in OSHA 1910:

APFR

Which of the following circuits cannot be grounded:

All of the above

Boundary least to worst

Arc flash boundary limited approach boundary restricted approach boundary prohibited approach boundary

Which NFPA 70E article covers placing equipment in an electrically-safe work condition?

Article 120

What type of switch is required for an incoming service of 3000-4000A?

Bolted-Pressure Switch

A wire wound on a metal pipe will have which of the following:

Both resistance and inductance

What does CPR stand for?

Cardiopulmonary Resuscitation

Oxidation of copper contacts will be severe in areas, which contain?

Chemical fumes

Apparent Power

Circuits Impedance (Z)

Reactive Power

Circuits Reactance (X)

OSHA 1910.146

Confined Spaces

Power Factor

Cos Theta

CO-6 curve by IEEE standrard

Definite Minimum

Which of the following protection element tests would you most likely NOT perform on a new 21 device?

Determine time delay

Which of the following ground fault detection methods involves sensing current in only one conductor?

Direct method

Which of the following is not a rule of thumb when concerning arc flash

Each layer of under arc-rated clothing reduces the heat to the body by 50%

OSHA 1910.334

Electrical Use of Equipment

OSHA 1910.333

Electrical Use of Work Practices LOTO

OSHA 1910.137

Electrical protective devices

Direct-current bus arrangement must be arranged positive to negative from front to back, top to bottom, or left to right, as viewed from the front of a switchboard, switchgear, or panelboard.

False

Medium-voltage cable, in accordance with NEC Article 328, is defined as single or multiconductor solid dielectric insulated cable rated at 2000 volts or higher for use on power systems rated up to 35kV.

False

Unbroken busway lengths shall not be extended through drywall

False

Wiring diagrams should show all components in a circuit, arranged without regard to their actual physical location.

False

The main breaker and the feeder breakers all have instantaneous trip functions in the overcurrent trip devices. Which of the following statements is true?

Feeder breakers and/or the main breaker may trip

OSHA 1910.155

Fire Protection

Which of the following would be a factor in choosing between 100%, 133%, and 173% Medium voltage cable for a power system?

Ground Fault Protection

After a conductor or circuit part has been deenergized and Lockout-Tagout (LOTO) applied and verified, which of the following is the best way to release stored energy?

Ground the conductor or circuit part

OSHA 1910.138

Hand Protection

OSHA 1910.147

Hazardous Energy Control

Resistance Reactance Impedance Triangle

Hypotenuse = Impedance Z^2=R^2+X^2

Power Triangle

Hypotenuse is Apparent Power

Partial discharges are created by:

Ionization of air pockets within the insulation

Oil SG less than 1 where do I pull the sample

Less than 1 means it is less than water and will float to the top which means we should pull the sample from the bottom

Ground fault protection system is provided for the protection from line to line ground faults that occur on the _____ of the service disconnect means.

Load side

What does LEL stand for?

Lower Explosive Limit

Primary and Secondary Simple Radial System

Main breaker feeds secondary feeder breakers that go to loads.

What does NERC stand for?

North American Electric Reliability Corporation

Power transformer cooling classes went through major changes in the United States when IEEE Standard C57.12.00-2000 adopted the modern four-letter designation. Which of the following old designations does not match the new?

OA/FOA = ONAN/ONAF

Radial System Electrical

One primary fused switch and Transformer to feed a main bus

Expanded Radial system

One utility breaker feeds 2 xfmr's and 2 busses

A drawing the principally shows the flow of electrical power is a what

One-Line

Which portion of the transmission system experiences faults occur most frequently?

Overhead lines

OSHA 1910.134

PPE/Respiratory Protection

OSHA 1910.157

Portable Fire Extinguisher

You walk up to a transformer to obtain an oil sample. What is the first thing you should check before opening the drain valve?

Pressure gauge

Primary Loop system

Primary main breaker feeds parallel to two loop feeders and both loads can be fed by either breaker hence the loop

An electrical system that is not typically used in an industrial application

Redundant system

True Power

Resistive element

OSHA 1910.269

Special Industries, Electric Power Generation, Transmission, and Distribution

OSHA 1926.1053

Stairways and ladder

When performing atmospheric tests on a confined space:

Test oxygen level first

Solar photovoltaic systems, fuel cell systems, wind electric systems, energy storage systems, or interconnected electric power production sources are permitted to be connected to the supply side of the service disconnecting means

True

OSHA 1910.23

Use of Ladders

OSHA 1910.25

Use of Scaffolding

Arc Flash Boundary

Where a person can receive 2nd degree burns

3 capacitors: 12, 20, and 30micro farads are connected in series to a 400Hz source. The total Xc is what?

Xc=1/(2)(Pi)(f)(F) Xc=1/(2)(Pi)(400)(6x10^-6)= 66.31 ohms

The safety glasses or goggles suitable for electrical work should

be non conductive

The amp rating of the trip device in a breaker is the

continuous current rating

Which of the following relay is provided as the primary protection of transmission lines:

distance

The training required by NFPA 70E for electrical safety shall be:

either in classroom or OTJ

Polarized capacitors are also known as _____ capacitors.

electrolytic

What does a kilowatt-hour meter read?

energy use

What is the primary advantage of sulfur hexafluoride gas as an insulator?

its insulating strength increases with pressure

Dielectric strength of SF6 is

less than that of oil used in OCB

The smallest particle of a substance where it still retains it�s properties is a/an______.

molecule

Oil SG greater than 1

pull sample from top since the water will be able to float on top of oil

The isolating switch installed near disconnecting means shall be accessible to only

qualified persons only

A ________ rated switchboard has a main circuit protection device that is equal to or greater than the available fault current, but subsequent downstream circuit protection devices connected in series have a lower interrupting rating.

series

Ungrounded service conductors between the terminals of service equipment and service conductors are what

service entrant conductors

A face shield has 11 cal/cm^2 rating on it. What does this mean

you have a 50% chance of receiving 2nd degree burns on bare skin

XL

(2)(Pi)(f)(L)

Class 00 gloves BRWYGO

(BEIGE) max use 500VAC tested at 2500 VAC

Class 3

(GREEN) Max use 26,500 VAC tested at 30,000

HP Torque equation

(HP*5252)/(RPM)=Torque

Class 4

(ORANGE) max use 36,000VAC tested at 40,000

Class 0

(RED) max use 1000VAC tested at 5000

Class 1

(WHITE) max use 7500VAC tested at !0,000

Class 2

(YELLOW) max use 17000VAC tested at 20,000

write three thousand fortyeight tenthousanths in decimal form

0.3048

PPE levels

1- 4cal 2- 8 cal 3- 25 cal 4- 40 cal

Xc=

1/(2)(Pi)(f)(C)

Atmospheres that contain a flammable component above what percent of its Lower Explosive Limit (LEL) are considered hazardous for confined space entry?

10%

If a current of 30 amps is measured with a 100 amp 3% ammeter, the maximum possible error in terms of actual error is:

10%

What is the maximum deviation allowable between fuse resistances in a new medium-voltage motor starter?

15%


Ensembles d'études connexes

Physics 222 Exam 1 (H/A/Practice Test Questions)

View Set

MGMT 309 Exam 1 (ch. 1-4 quizzes)

View Set

NURS 7470 Exam 3 Practice Questions

View Set

Mastering Biology - Chapters 10 and 11 Assignment

View Set

Chapter 2: Europeans Encounter the New World

View Set

Unit 2: The Constitution and Federalism

View Set