From owner-freebsd-questions@FreeBSD.ORG Fri Oct 18 04:05:02 2013 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 2338682B for ; Fri, 18 Oct 2013 04:05:02 +0000 (UTC) (envelope-from erich@alogt.com) Received: from alogt.com (alogt.com [69.36.191.58]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id E7F8D28DE for ; Fri, 18 Oct 2013 04:05:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=alogt.com; s=default; h=Content-Transfer-Encoding:Content-Type:Mime-Version:References:In-Reply-To:Message-ID:Subject:Cc:To:From:Date; bh=/y48hW9vywm0MKjdqJvDJ1z80KrZxXEQdZVd3rs1Jos=; b=PwDhGvoQK9eNOCsiAacDpuJv3RHEQK/b+BXIbs8FyBLiENlM1NSg7prZ/wAmX7uIzZOkBUM5n/dr4gTANZGA9Uwiult88bQVYhp0o3m/TB8ZqTvjpy4vpXGws/0kr+HTU06AsG+2LopD/qdEl0fOTaZH54pg2aHyNLUMuWiMZUw=; Received: from [39.194.172.110] (port=63140 helo=X220.ovitrap.com) by sl-508-2.slc.westdc.net with esmtpsa (SSLv3:DHE-RSA-AES128-SHA:128) (Exim 4.80.1) (envelope-from ) id 1VX1Iw-001yVj-O0; Thu, 17 Oct 2013 22:04:53 -0600 Date: Fri, 18 Oct 2013 12:04:41 +0800 From: Erich Dollansky To: Ralf Mardorf Subject: Re: OT: UPS buying suggestion Message-ID: <20131018120441.175b7e7d@X220.ovitrap.com> In-Reply-To: <1382015735.5852.100.camel@archlinux> References: <525F0138.1020304@fjl.co.uk> <20131017093820.6a8428de@X220.ovitrap.com> <1381988697.5852.16.camel@archlinux> <20131017142910.61325830@X220.ovitrap.com> <1381992680.5852.45.camel@archlinux> <525FD4C8.1090600@fjl.co.uk> <1382015420.5852.97.camel@archlinux> <1382015735.5852.100.camel@archlinux> Organization: ALO Green Technologies X-Mailer: Claws Mail 3.9.2 (GTK+ 2.24.19; amd64-portbld-freebsd10.0) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - sl-508-2.slc.westdc.net X-AntiAbuse: Original Domain - freebsd.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - alogt.com X-Get-Message-Sender-Via: sl-508-2.slc.westdc.net: authenticated_id: erich@alogt.com X-Source: X-Source-Args: X-Source-Dir: Cc: freebsd-questions@freebsd.org X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 18 Oct 2013 04:05:02 -0000 Hi, On Thu, 17 Oct 2013 15:15:35 +0200 Ralf Mardorf wrote: > On Thu, 2013-10-17 at 15:10 +0200, Ralf Mardorf wrote: > > On Thu, 2013-10-17 at 13:15 +0100, Frank Leonhardt wrote: > > > On 17/10/2013 07:51, Ralf Mardorf wrote: > > > > On Thu, 2013-10-17 at 14:29 +0800, Erich Dollansky wrote: > > > > > > > Most RCCB (aka ELCB, RCD) work (hereabouts anyway) work with > > > counter-wound coils on the input and output of the supply such > > > that he magnetic field is neutral if the current is the same. If > > > it goes out of balance, it trips the switch. Normally 30mA > > > difference is the rule. They don't have a value, as such. I heard > > > that only 10mA is needed to interrupt your heart, but I've also > > > heard 100mA. They're all potentially dangerous. It depends on the > > > route taken by the current passes through your body > > Correct, I've got professional literature about this issue, but I'm to > lazy top take a look now. Don't trust a RCCB! > the individual resistance of the person getting in contact is much more important. I know a person who gets an electric shock touching 12V DC because his body's electrical resistance is very low. Most people I know and tested have a resitance between two fingers of 20 to 30kOhm. On the other extreme, I have more than 1MOhm. > > As mentioned before, a workshop in addition must use an isolating > > transformer, by this galvanic isolation you can't get an electric I highly doubt this. Only larger workshops have a transformer. They are getting 20kV and more supplied and need the transformer for a different reason. Erich