Article View: sci.electronics.design
Article #1608Re: Understanding a split-mode power supply.
From: Sylvia Else
Date: Mon, 05 Jan 2009 03:04
Date: Mon, 05 Jan 2009 03:04
56 lines
3490 bytes
3490 bytes
legg wrote: > On Mon, 05 Jan 2009 09:28:54 +1100, Sylvia Else > <sylvia@not.at.this.address> wrote: > >> Phil Allison wrote: >>> "No legg to stand on " >>> >>>> This assembly was designed to fail in a safe manner - no fire, >>>> explosion or shock hazard was intended to result from a single fault >>>> resulting in the fusing of the emitter resistor. However, this does >>>> not mean that the repaired unit will meet the same standards. The >>>> events that occurred may have affected the safety isolation of >>>> magnetic isolators in such a way that a second similar event may not >>>> be as benign. >>> >>> >>> ** Jesus Christ - >>> >>> get fucking real you asinine fucking WOG WANKER !! >>> >>> The WHOLE damn AC unit is metal encased, installed & MAINS earthed >>> !!!! >> Leaving aside the abuse, I confess this was my sentiment as well. And >> not only that, neither the outside nor inside units even get touched in >> the normal way of things. >> >> The entire board could go up in flames, if it were inflammable, and >> still cause nothing more than a bad smell. Since it's outside even the >> resulting fumes wouldn't be a threat. >> >> Sylvia. > > I see that specific poster's dialog in your response, only. His actual > postings get filtered autiomatically here. > > The unit is unlikely to go up in flames, for good reasons. > > As a technician, you'd be advised to follow industry standards in > repair of any line-isolating assembly. One doesn't always know the > n'th reason why something was done. > > A hipot is not impossible to arrange, locally, if you don't have the > equipment yourself. > > RL My test repair with a non-fuisible resistor and an NPN transistor from my stock seems to have worked (rather to my surprise), so I'll have to source a fusible resistor now. I'll take your comment about a hi-pot on board, though in fact I've only worked on the high voltage side of the system - the transformer hasn't been touched. Still, I suppose insulation breakdown in the transformer could be implicated in the original failure. Sylvia.
Technical Details
Message-ID:
<496178af$0$32004$afc38c87@news.optusnet.com.au>Path:
arc1-ca.pugleaf.net!g2news1.google.com!news1.google.com!border1.nntp.dca.giganews.com!nntp.giganews.com!nx02.iad.newshosting.com!newshosting.com!novia!news1.optus.net.au!optus!newsfeeder.syd.optusnet.com.au!news.optusnet.com.au!not-for-mailReferences:
<49601fcc$0$26314$afc38c87@news.optusnet.com.au> <qaa0m4poq9ppo2l7prp91o9bmko9s0mj96@4ax.com> <49602fd0$0$26849$afc38c87@news.optusnet.com.au> <rpe1m410f1srnjirgihrdnb9nsj52d27d5@4ax.com> <6sbtutF573dnU1@mid.individual.net> <49613826$0$19954$afc38c87@news.optusnet.com.au> <e1s2m45i5fs7lapv7dmjuargom8mv3tbc2@4ax.com>Show Full Headers
Complete Article Headers
X-Google-Thread: 1131b0,3f5de0c6e381c3d6 X-Google-Thread: 103407,3f5de0c6e381c3d6 X-Google-Attributes: gid1131b0,gid103407,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: arc1-ca.pugleaf.net!g2news1.google.com!news1.google.com!border1.nntp.dca.giganews.com!nntp.giganews.com!nx02.iad.newshosting.com!newshosting.com!novia!news1.optus.net.au!optus!newsfeeder.syd.optusnet.com.au!news.optusnet.com.au!not-for-mail Date: Mon, 05 Jan 2009 14:04:15 +1100 From: Sylvia Else <sylvia@not.at.this.address> User-Agent: Thunderbird 2.0.0.19 (Windows/20081209) MIME-Version: 1.0 Newsgroups: sci.electronics.design,sci.electronics.repair,aus.electronics Subject: Re: Understanding a split-mode power supply. References: <49601fcc$0$26314$afc38c87@news.optusnet.com.au> <qaa0m4poq9ppo2l7prp91o9bmko9s0mj96@4ax.com> <49602fd0$0$26849$afc38c87@news.optusnet.com.au> <rpe1m410f1srnjirgihrdnb9nsj52d27d5@4ax.com> <6sbtutF573dnU1@mid.individual.net> <49613826$0$19954$afc38c87@news.optusnet.com.au> <e1s2m45i5fs7lapv7dmjuargom8mv3tbc2@4ax.com> In-Reply-To: <e1s2m45i5fs7lapv7dmjuargom8mv3tbc2@4ax.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Lines: 57 Message-ID: <496178af$0$32004$afc38c87@news.optusnet.com.au> NNTP-Posting-Host: 122.106.220.150 X-Trace: 1231124655 32004 122.106.220.150