1. General Information for Electrical Installations
Chapter One
General Information for Electrical Installations

2. Objectives After studying this chapter, you should be able to:
Understand the basic safety rules for working on electrical systems
Access the Internet to obtain a virtual unlimited source of safety and technical related information 2

3. Objectives (cont’d.)
Become familiar with important electrical codes, safety codes such as NFPA 70, 70A, 70B, 70E, 73, OSHA, NIOSH, ADA, NRTL, and the ICC
Learn about licensing, permits, plans, specifications, symbols, and notations
Understand the role of the electrical inspector and the International Association of Electrical Inspectors 2

4. Objectives (cont’d.) Understand the metric system of measurement
Understand the role of nationally recognized testing laboratories (NRTLs) and the necessity for listed equipment 2

5. Safety in the Workplace
Safety First… Safety Last… Safety Always!
There are dangerous voltages in residential electrical work
Shocks can cause secondary hazards such as falling
Fault currents can cause arc blasts 4

6. Safety in the Workplace (cont’d.)
Lockout/Tagout (LOTO): physical restraint of all hazardous energy sources that supply power to a piece of equipment
Safety measures are required by law
Practice good housekeeping 5

7. FIGURE 1-3 A lock-off accessory that can be added to circuit breakers allows for adding a padlock and tag to in circuit breakers allows for adding a padlock and tag to individual circuit breakers in a panelboard. © Cengage Learning 2015

8. Safety in the Workplace (cont’d.)
Only qualified persons may work on energized or “live” equipment
The NEC® defines a qualified person as:
“One who has skills and knowledge related to the construction and operation of the equipment and has specific safety training on the hazards involved”
Reprinted with permission from NFPA

9. Personal Protective Equipment
Includes rubber gloves, insulating shoes and boots, face shields, safety glasses, hard hats, etc.
OSHA states that:
Employers should provide training on personal protective equipment (PPE) use
Conductive jewelry should not be worn if contact with exposed energized parts is a possibility

10. Arc Flash
On large electrical installations, an arc flash can generate temperatures of 35,000°F
Don’t get complacent when working on electrical equipment
Don’t be fooled by the size of the service
Don’t assume that if you cause a fault on the load side of the main disconnect that the main breaker will trip off

11. Arc Flash (cont’d.) Classifying electrical injuries
Time is important in life-threatening situations
Four main types of electrical injuries:
Electrical shock
Electrocution
Burns
Falls

12. Arc Flash (cont’d.) Steps to take in the event of electrocution:
Recognize that an emergency exists
Call 911 for experienced assistance
Don’t touch the person if he is in contact with a live circuit
Shut off electrical power
Perform CPR if person is not breathing
Timing is everything!

13. Arc Flash (cont’d.) Using the proper tools is vital
Digital multimeters
High-quality digital multimeters reduce the risk of electrical shock
Multimeters should be category rated based on location of the equipment to be tested
Cat IV: high fault current
Cat I: very low fault current

14. Training Take advantage of safety seminars
Participate in formal training programs such as OSHA’s Training Institute
Use the Internet to obtain safety information

15. Safety Cannot Be Compromised!
Don’t take chances!
Use the right tools!
Turn off the power
Follow a lockout/tagout procedure
Mark the tag with a description of exactly what that particular disconnect controls
Visit safety websites for information

16. Licensing and Permits
Electrical licensure of electricians and contractors is generally required
Most communities require electrical permits
Electrical permits document what work is to be done, who is doing the work, and inspection schedules 8

17. Licensing and Permits (cont’d.)
Homeowners are usually allowed to pull permits and do electrical work on their own home where they live
Construction requirements are provided in the construction plans, prints, or drawings 9

18. Plans and Specifications
The plans convey details for construction and contain a materials list
Specifications
Normally accompany each set of plans
Written instructions and information about job
Prevent confusion of details.
Take preference over the plans if a difference between the two exists 11

19. Symbols and Notations
Symbols and notations are used to simplify drawings
Symbols are standard graphics as adopted by the American National Standards Institute (ANSI)

20. Symbols and Notations (cont’d.)
Symbols present information about devices, appliances, and equipment
Notations are on the drawing in the form of text and generally next to the symbol that needs additional explanation

21. The National Electrical Code® (NEC®)
The NEC® provides a standard for electrical work that is widely adopted by local governments
The NEC® is sponsored by the National Fire Protection Association (NFPA) 15

22. NEC® (cont’d.) The NEC® is constantly being revised
A new code is published every three years
Obtain latest edition of the NEC NFPA 70
National Fire Protection Association
The International Association of Electrical Inspectors (IAEI) 16

23. NEC® (cont’d.)
Definitions of electrical terms are often found in Article 100 of the NEC®
The 2011 edition is the most recent, but many locales still use older editions
Electrical installations have to comply with other community-adopted building codes and standards 17

24. NEC® (cont’d.) Electrical Inspection Code for Existing Dwellings
Published by NFPA; referred to as NFPA 73
Evaluates safety, fire, and shock hazards of the electrical installation
For electricians doing remodel work
For inspectors in bringing an existing dwelling to a safe condition 28

25. Building Codes Other code organizations
ICC, ANSI, IAEI
Know code definitions (NEC® 90, 100)
Read 110.3(B) carefully!
“Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.”
Reprinted with permission from NFPA 29

26. Metrics (SI) and the NEC®
Metric and standard systems are both supported by the NEC®
Calculations using metrics or standard result in slightly different values
Calculations in either metrics or inch-pounds are in compliance with the NEC®, 90.9(D)

27. Listed Equipment and Nationally Recognized Testing Laboratories
OSHA rules state that: All electrical products installed in the work place shall be listed, labeled, or otherwise determined to be safe by a nationally Recognized Testing Laboratory (NRTL).

28. Listed Equipment and NRTL (cont'd.)
The American National Standards Institute (ANSI) works with Underwriters Laboratories (UL) and other organizations to set basic standards for electrical equipment
NRTL is the “third party,” testing products in an effort to reduce safety risks

29. Listed Equipment and NRTL (cont'd.)
After the NRTL tests the product and it complies with the safety standard, the product is then listed and will have listing markings, or labels

30. Listed Equipment and NRTL (cont'd.)
Products are tested for safety
Tested products that meet the safety standard are listed and labeled
A listed product must be used and installed properly to assure safety 22

31. Listed Equipment and NRTL (cont'd.)
Some recognized testing laboratories
Underwriters Laboratories, Inc. (UL®)
CSA International, formerly known as the Canadian Standards Association
Intertek Testing Services NA, Inc. (ITS)
National Electrical Manufacturers Association (NEMA) 24