Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums > AC Power and Grounding

Power & Grounding reading material & resources

(1/3) > >>

Jonathan Johnson:
A few resources for those who want to learn more about electrical wiring & grounding. Please post additions to this list. Most of the resources listed are written for the U.S./North America market; since this is an international forum it would be helpful to have some resources written for other regions of the world.

Books:

* Electricity for the Entertainment Electrician by Richard Cadena
* Practical Electrical Wiring by Richter & Hartwell -- a general guide for the most common wiring methods & practices, both residential and commercial
* Wiring Simplified, by Richter, Schwan, & Hartwell -- a "Reader's Digest condensed" version of the aboveWhite papers:

* Power distribution and grounding by Middle Atlantic (PDF)
* Power and Grounding by Jim Brown, et al; published by SurgEx (if this link gets broken, try the SurgeX Library link below)Websites:

* SurgeX Library
* Mike Holt Enterprises -- comprehensive site dedicated to electrical education (check out the forums)Codes (International):

* India: IS SP 30: National Electrical Code (2011) -- Published by the Bureau of Indian Standards
* United States: NFPA 70: National Electrical Code -- published by the National Fire Protection Association (NFPA) in the United States; adopted by most jurisdictions in the United States as enforced electrical code. Updated every three years.
Lastly, consider that "best practices" in electrical wiring methods and materials will change over time. Old versions of electrical books should be avoided because they may present methods and materials that are no longer considered acceptable.

And a gem from Jim Brown's white paper:

--- Quote ---The international differences between power systems are limited to the line voltages (100, 120 or 23 0 volts), the frequency (50 or 60 Hz), and details of how neutrals and grounds are handled.
--- End quote ---

Jonathan Johnson:
Diagram of different receptacles in common use in North America:

Courtesy of Wikipedia

Notes:

* NEMA 6-series: Nominally 250V. The grounding conductor supplying this receptacle might be conduit or a derated, bare or green insulated conductor (such as an 8 AWG copper ground conductor with 6 AWG copper hot conductors). The grounding conductor is not intended to serve as a neutral, therefore it is not permissible to derive 125V power from this receptacle. 6-50 is typically used with welders.
* NEMA 10-series: Nominally 125/250V. This receptacle has a shared grounding/neutral conductor. The neutral wire must be insulated and the same gauge as the hot conductors. In practice, this is often not the case; there are many poor installations that simply use an uninsulated grounding wire for the neutral connection. Note that the chassis of the appliance is bonded (connected) to the neutral wire at a terminal block where the cordset enters the appliance; there should be no other connection. 10-50 is typically used with kitchen ranges (and 10-30 for clothes dryers) prior to 1999, when their use was deprecated by the National Electrical Code; the 10-series are now classed as "ungrounded" receptacles and plugs.
* NEMA 14-series: Nominally 125/250V. This receptacle has separate ground and neutral conductors. The neutral conductor should be the same gauge as the hot conductors; the grounding conductor might be conduit or might be a derated, bare or green insulated conductor (for example, 6 AWG hot and neutral conductors; 8 AWG grounding conductor). 14-50 is typically used with kitchen ranges, but may be used for any application requiring both 125V and 250V power up to 50A. The 14-series effectively replaces the 10-series.
If you ever see a receptacle with two T-shaped slots, be very cautious and always test it against a separately-derived ground (i.e., a 3-wire extension cord plugged into a known, good receptacle). This receptacle, designated NEMA 2-15, was originally designed to be usable for either 125V or 250V; it is a very, very bad design because a person could connect a 125V appliance into 250V causing unpredictable results.

Jonathan Johnson:
Edited first post to include list of electrical codes by country. Please help us build this list!

Lyle Williams:

--- Quote from: Jonathan Johnson on November 24, 2013, 08:47:25 PM ---Edited first post to include list of electrical codes by country. Please help us build this list!

--- End quote ---

Australian wiring rules:
http://studentweb.bhtafe.edu.au/bhi/pluginfile.php/190201/mod_resource/content/1/wiringrules%20as3000.2007.pdf?forcedownload=1

Standard for regular testing and tagging of portable electrical equipment:
http://www.westvic.org.au/dmdocuments/Electrical_Safety_AS%203760-2003.pdf

Construction site and temporary wiring:
ftp://law.resource.org/nz/ibr/as-nzs.3012.2010.html

Michael Lascuola:
Thanks!

I'm getting a bad URL on:  Power distribution and grounding by Middle Atlantic (PDF)  (http://www.middleatlantic.com/pdf/PowerPaper.pdf)

Navigation

[0] Message Index

[#] Next page