Article 1017629 of alt.home.repair: Path: news.misty.com!not-for-mail From: nicksanspam@ece.villanova.edu Newsgroups: alt.comp.hardware.pc-homebuilt,alt.home.repair,alt.engineering.electrical,alt.tv.tech.hdtv,sci.electronics.basics Subject: Re: Surge / Ground / Lightning Date: 7 May 2008 08:09:42 -0400 Organization: Villanova University Lines: 39 Message-ID: References: NNTP-Posting-Host: acadia.ece.villanova.edu X-Trace: max.inside.misty.com 1210158556 26690 153.104.44.130 (7 May 2008 11:09:16 GMT) X-Complaints-To: abuse@misty.com NNTP-Posting-Date: Wed, 7 May 2008 11:09:16 +0000 (UTC) Xref: news.misty.com alt.comp.hardware.pc-homebuilt:485630 alt.home.repair:1017629 alt.engineering.electrical:181532 alt.tv.tech.hdtv:169888 sci.electronics.basics:278627 wrote: >nicksanspam@ece.villanova.edu wrote: >| I wonder if "ring mains" (an extra wire from the last outlet to make >| a loop back to the fusebox) are legal in the US. Seems like a nice way >| to improve voltage regulation with a little extra wire, and if the ring >| wire only breaks in one place, all the outlets keep working. > >It is not legal in the US. It is also considered technically unsafe. Lots of things are "technically unsafe" :-) Safety is often used as excuse for people-control... >The safest case would be wiring both ends of the ring into the same breaker >rated for the current capacity of the wire as if used in a regular branch >circuit. Sounds good to me. >... If the wire became loose at one point in the ring, it would still be >a potential hot spot Maybe not too hot, if the rest of the wire is intact. >... a neutral would have to be wired in from both ends of the ring, and >each be wired in a separate hole (not doubled up) in the neutral bus bar. The "separate hole problem" has lots of solutions. >... The issue of voltage stability is addressed by keeping branch circuits >short. It is my understanding that UK ring circuits tend to be longer and >run all around the portion of a house (often an entire floor). Sounds more cost-effective to me. Why don't more people use large PEX pipe "ring mains" with Ts, vs home runs with tiny pipe and expensive manifolds? Nick