ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals

>> Home   >> Electrical-Photos   >> Classifieds   >> Subscribe to Newsletter   >> Store  
 

Photos of the Week:

Old Fused Panel
Old Fused Panel

Advertisement:-Left
Recent Gallery Topics:
What in Tarnation?
What in Tarnation?
by timmp, September 10
Plumber meets Electrician
Plumber meets Electrician
by timmp, September 10
Who's Online Now
0 members (), 67 guests, and 22 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
#222235 06/02/23 04:19 PM
Joined: Mar 2004
Posts: 829
B
BigB Offline OP
Member
Is there a source for historical NEC info? Specifically I am interested in reading what was written about 3 wire range and clothes dryer circuits. I am familiar with the rules, SE cable only and fed from main panel, not allowed in mobile homes etc. but I would like to see the code articles if possible.

Horizontal Ad
Joined: Mar 2004
Posts: 829
B
BigB Offline OP
Member
Also, was the requirement that the 3 wire circuit originate at the service equipment only when the shared grounded/grounding conductor was un-insulated or was it required in all cases?

Joined: Jul 2004
Posts: 10,006
Likes: 37
G
Member
NFPA has either the actual code or the ROP draft on their web site going back to the 50s for a lot of cycles but not the 93 or any others in that era. In 1996 they finally accepted Phil Simmonds' proposal to eliminate that exception to the normal rules. He said "the war was over". It was originally a WWII thing to save copper. Bear in mind, this was a neutral, also used as a ground and neutrals shall be white, insulated. SE was the only cable that didn't require an insulated neutral but you could use the white wire in Romex. That resulted in a lot of installations where the ground was present if sparky didn't cut it off. A very common installation was the ground was hooked to the box and the neutral was hooked to the receptacle. Romex typically was going to have the ground anyway. The requirement that it be from the service disconnect enclosure where the MBJ lands was to avoid voltage drop in a feeder neutral that would impose voltage on the frame of the equipment. Most manufactures still wanted you to add an additional ground wire to a convenient EGC from another circuit, usually the receptacle for the washer or a small appliance circuit although I doubt ranges frequently got it. If it was Romex and they did ground the box with the bare wire, it was easy to install the 4 prong receptacle. Everything was there.
This is the 1990 code.

[Linked Image from gfretwell.com]


Greg Fretwell

Link Copied to Clipboard
Advertisement:-Right


Tools for Electricians
Tools for Electricians
 

* * * * * * *
2023 National Electrical Code (NEC)
2023 NEC + Exam Prep Study Guides Now Available!
 

Member Spotlight
CharlieE
CharlieE
Indianapolis
Posts: 201
Joined: April 2004
Top Posters(30 Days)
BigB 2
Popular Topics(Views)
352,586 Are you busy
276,310 Re: Forum
255,750 Need opinion
New Page 2
Powered by UBB.threads™ PHP Forum Software 7.7.5