Article View: sci.electronics.design
Article #1354Re: Tingles from power supply
From: VWWall
Date: Tue, 10 Mar 2009 22:26
Date: Tue, 10 Mar 2009 22:26
37 lines
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3331 bytes
john@jjdesigns.fsnet.co.uk wrote: > Eeyore wrote: >> >> Needless to say there's a reason for the method which as I said you'll find in the >> EXCELLLENT app notes at powerint.com. It surprised me too. > > That truly is an excellent site. I went to have a quick check to check > on this puzzle and was there an hour. Will be returning. Note this one: (From an15.pdf) "(2.1.10): Equipment shall be so designed that at an external point of disconnection of the mains supply, there is no risk of electric shock from stored charge on capacitors connected to the mains circuit. Equipment shall be considered to comply if any capacitor having a rated capacitance exceeding 0.1 uF and connected to the external mains circuit, has a means of discharge resulting in a time constant not exceeding 1 second for pluggable equipment type A (non-industrial plugs and socket-outlets). This requirement specifically applies to any EMI filter capacitor connected directly across the AC mains which could cause a shock hazard on the exposed prongs of an unplugged power cord." One could easily touch both pins of a supply plug within one second! > Only means they have is the naff bridging capacitor, which results in > the leaking AC, the tingles and the sparks in the dark. > Ban the damned things, that's what I say :) This can become especially bad with mis-wired outlets! Many internal power supplies have RFI suppression capacitors wired between each line and the chassis, which is supposed to be grounded through the "equipment ground" in the US, or the equivalent in other countries. -- Virg Wall, PE
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X-Google-Thread: 112d1e,5985c699c60fb1f8 X-Google-Thread: 103407,5985c699c60fb1f8 X-Google-Attributes: gid112d1e,gid103407,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: arc1-ca.pugleaf.net!g2news2.google.com!news1.google.com!Xl.tags.giganews.com!border1.nntp.dca.giganews.com!nntp.giganews.com!local01.nntp.dca.giganews.com!nntp.earthlink.com!news.earthlink.com.POSTED!not-for-mail NNTP-Posting-Date: Tue, 10 Mar 2009 17:26:12 -0500 Date: Tue, 10 Mar 2009 15:26:14 -0700 From: VWWall <vwall@large.invalid> User-Agent: Thunderbird 2.0.0.14 (X11/20080514) MIME-Version: 1.0 Newsgroups: sci.electronics.design,aus.electronics Subject: Re: Tingles from power supply References: <00b89736$0$7237$c3e8da3@news.astraweb.com> <pan.2009.03.09.20.20.12.51572@example.net> <49B590CB.7145F087@hotmail.com> <3cc53687-b529-4c4e-908e-a727fefd5c9f@y13g2000yqn.googlegroups.com> <49B5C6D5.B77ACD34@hotmail.com> <73697af8-4169-472d-abeb-dc61210dad77@l16g2000yqo.googlegroups.com> In-Reply-To: <73697af8-4169-472d-abeb-dc61210dad77@l16g2000yqo.googlegroups.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Message-ID: <DqOdnW6RupiZdCvUnZ2dnUVZ_vyWnZ2d@earthlink.com> Lines: 37 X-Usenet-Provider: http://www.giganews.com NNTP-Posting-Host: 71.105.66.41 X-Trace: sv3-WY3INgR68aS1qvSi+IzZNwdolrbVY/KKDd8Hnv/9ip5C7bY+lPKTV0kIiB8lb17CdIaAkMynfgzKAOO!9c/1B0lHlBVDjzi8Y5d3PnXT6BpPxzBo6hKmPeDtyXt0oOZ2kyWAZbAKCrwN0UcLux5G8lutlqYr!A+oyevgf7bRDdIqfzR9syF2jy5u5 X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.39