From a general industry electrical hazards and arc flash course. An archived deck: check it against the current standard before teaching from it.
Slide text
· 21 slides · by Workplace Safety Awareness Council
The words on each slide as the author wrote them, read from the file by software so they can be searched. Layout, pictures and tables are not shown here: the slides above and the download are the original.
- Slide 1
Wiring Design and Protection
- Including
- Ground Fault Circuit Interrupters
- Slide 2
Introduction
- This material was produced under grant number SH-16615-07-60-F-12 from the Occupational Safety and Health Administration, U.S. Department of Labor. It does not necessarily reflect the views or policies of the U.S. Department of Labor, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government.
- This material was produced by the Workplace Safety Awareness Council, a 501(c)(3) not-for-profit organization dedicated to safety in the workplace. For further information about the council or upcoming safety related training, please visit our website at www.wpsac.org or call us at (863) 537-4053.
- Slide 3
Ground-Fault Circuit Interrupter
- This device protects you from dangerous shock
- If a ground fault is detected, the GFCI can shut off electricity flow in as little as 1/40 of a second, protecting you from a dangerous shock
- Slide 4
Ground Fault Receptacles
- 1910.304(b)(3)(i) & (b)(3)(ii)(A)
- GFCI are required:
- in bathrooms
- on rooftops
- temp wiring for maintenance, remodeling or repair
- extension cords if used for temp. electric power
- receptacles used for equipment in damp or wet locations
- Slide 5
Outlet devices
- Outlets shall not be rated for less than the circuit load
- Slide 6
Clearance for Overhead Lines
- 1910.304(c)(2) - Table S-6
- Separation of Overhead Lines & Pedestrians
- Installations on or after August 13, 2007
- 10’ Clearance – less than 150V to ground
- Examples include:
- Finished grade
- Side walks
- Slide 7
Clearance for Overhead Lines
- 1910.304(c)(2) - Table S-6
- Separation of Overhead Lines & Vehicles / Equipment
- Installations on or after August 13, 2007
- 12’ Clearance – less than 300V to ground
- Examples include:
- Residential property and driveways
- Commercial area subject to vehicular traffic other than truck
- Slide 8
Clearance for Overhead Lines
- 1910.304(c)(2) - Table S-6
- Separation of Overhead Lines & Vehicles / Equipment
- Installations on or after August 13, 2007
- 15’ Clearance – 301V – 600V to ground
- Examples include:
- Residential property and driveways
- Commercial area subject to vehicular traffic other than truck
- Slide 9
Clearance for Overhead Lines
- 1910.304(c)(2) - Table S-6
- Separation of Overhead Lines & Vehicles / Equipment
- Installations on or after August 13, 2007
- 18’ Clearance – Less than 600V to ground
- Examples include:
- Public streets, alleys, roads and driveways
- Commercial area subject truck traffic
- Other land traversed by vehicles (i.e. cultivating, forests)
- Slide 10
Clearance From Building
- Openings
- 1910.304(c)(3)(i)
- 3’ from windows, doors, porches, fire escapes, balconies etc.
- Service conductors may not be below openings through which materials may be moved
- Slide 11
Overcurrent Protection
- 1910.304(f)(1)(iv) – (ix)
- Overcurrent protection:
- Readily accessible to building management personnel
- Not be located where they could be damaged
- Breakers clearly indicate whether on or off
- If operated vertically up position is on
- C.B. shall be marked SWD if used as switches
- C.B. rated 120/240 used only on 120/240 circuit panels
- C.B. rated 277/480 used only on 277/480 circuit panels
- Slide 12
Appliances to be Grounded
- 1910.304(g)(6)(iii) & 1910.304(g)(6)(iv)(A)
- Ranges, ovens, counter cooking units, clothes dryers if within 8’ vertically or 5’ horizontally of grounded objects
- Hazardous locations
- Supplied by metal clad, metal sheathed or metal raceway
- Any terminal at over 150v to ground
- Slide 13
Appliance Requirements
- 1910.305(j)(3)(ii) – (iii)
- Appliances
- Shall have a disconnecting means
- Shall have nameplate with rating in volts and amps or in volts and watts
- Slide 14
Equipment Grounding
- 1910.304(g)(6)(vi)(C)(1) – (6)
- Equipment Shall be Grounded
- Refrigerators, freezers, and air cond.
- Clothes washer, dryer, dishwasher, sump pumps, aquarium equipment
- Motor tools
- Hedge clippers, lawn mowers, snow blowers, wet scrubbers
- Appliances in wet locations
- Portable X-ray
- Portable hand lamps
- Slide 15
Wiring System
- Prohibitions
- 1910.305(a)(1)(iii)
- No wiring system installed in ductwork used to transport dust, loose stock, flammable vapors, or ducts for commercial cooking equipment
- Slide 16
Temporary Power & Lighting
- 1910.305(a)(2)(i)(B)
- Temporary Power & Lighting not to exceed 90 days (i.e. Christmas lighting, carnivals, etc.)
- This also includes experimental work and emergencies
- Slide 17
General Wiring
- 1910.305(a)(2)(v)(C)
- No branch – circuit conductors may be laid on the floor
- All lamps for general illumination shall be protected
- Flexible cords and cables shall be supported
- Slide 18
Distinguishing Conductors
- 1910.305(f)(3)
- Conductors must be distinguished by color or other means
- Grounded conductor
- Ungrounded conductor
- Grounding conductor
- Slide 19
Motors
- 1910.305(j)(4)(i)
- Motors
- Disconnecting means “within sight of” and not more than 50’ away
- Disconnecting shall plainly indicate whether off or on
- Disconnecting means shall be readily accessible
- Slide 20
Transformer Vaults
- 1910.305(j)(5)(vii) – (viii)
- Any pipe or duct system foreign to the electrical installation may not enter or pass through the vault
- Materials may not be stored in vaults
- Slide 21
Amusement Rides
- 1910.306(k)(2)(ii)
- Amusement rides and attractions shall be not less than 15’ in any direction from overhead conductors of 600V or less. For conductors over 600V they cannot be below and within 15’
