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Thread ID: 28360	2002-12-17 09:39:00	Problems... about the motherboard and power pack :(	ConCon (1839)	Press F1

Post ID	Timestamp	Content	User
106899	2002-12-18 21:45:00	Sorry Crozier, in an ideal world that is what one would hope for, but the legal situation under the Electricity Act and Regulations is not that black and white. Very few computer shops would have any person qualified by way of an appropriate form of Electrical Registration (usually Electrical Service Technician or EST) and holding a current Practising Licence. Currently, provided that the computer tech does not expose live mains electrical connections it is arguable that they are not carrying out prescribed electrical work. Replacement of power supply modules is really the only component that could classify and this is not dissimilar to the one time use of plug packs by security alarm installers to get around the wiring regulations. It doesn't matter whether the modular power supply is internal or external, if there are no exposed mains connections to make or repair then there is no element of prescribed work, any more than there would be for a person who replaces vacuum cleaner hoses or changes the agitator in a washing machine i.e. there is no electrical component in the work. Having said that, the law will soon change (January 2003) and will require testing, inspection and certification of all electrical appliances after servicing. While testing is not prescribed work under the Act, certification may only be carried out by a registered and licensed electrical worker. Before anybody decides to question the status of computers in all of this, the definition of an electrical appliance is any device that uses, or is designed or intended to use electricity and this includes devices whose primary function uses another form of energy, i.e. a gas heater or cooker with an electrical timer. So, from early 2003 onwards we can expect a crack down on computer shops where the work is carried out by persons without electical training or licensing. The level of training required is not arduous however and is primarily safety based. The minimum level of Registration required will be EST A and this can be obtained through a short course of Polytech evening classes. So, I repeat my advice to ConCon, turn it off and leave it off. then get a licensed electrician to come and check the power point and switchboard earth if necessary. Although my own background is in electronics, I do not recommend getting an electronics technician to check it as they usually do not have the experience or equipment to test mains earthing. All the evidence points to an earthing problem and although it is probably only leakage current fron mains filtering components that is causing the tingles, I wouldn't like to be the one to verify that it is something more dramatic by falling in a heap on the carpet. Cheers Billy 8-{)	Billy T (70)
106900	2002-12-18 22:10:00	I was under the impression that someone on site in a supervisory role had to hold at least EST1 because the techs are working on stuff that plugs into the power supply. That's what the told us at Massey last year.	crozier (2004)
106901	2002-12-18 22:49:00	its a grey area at the mo. i wouldn't mind betting that more people have had shocks from badly wired extension leads than from working on pc's. had a similier thing happen to one of my 'trades' where OSH tried to set safty rules. they got told where to go simply because if the put the rules in the whole industry would collasp as the cost to consumers would double if not triple. considering its not an industry which has many accidents anyway, they decided not to put the changes in.	tweak'e (174)
106902	2002-12-19 20:28:00	Bad news tweak'e, the Regulation changes were Gazetted yesterday and take effect from 1 January 2003. Safety testing is not something to be taken lightly and if it takes legislation and regulation to get people to carry out basic safety checks that they should do for the safety of themselves and their customers then so be it. From my own experience I know that it sometimes seems pointless to carry out insulation and earthing tests time after time with no fault found, but once in a while you find a fault that could have killed and boy do you feel good about your testing regime when that happens. Even moulded plug tops can be found with open earths or P-N reversals and fortuitous phase connections to ungrounded metal cases do happen. It's like safety checks on aeroplanes, only a tiny fraction of the number performed ever find a fault but even then some faults get through and I'm not talking about Air NZ here. I see in this morning's Herald that a wheel fell off a topdressing aircraft yesterday. Nobody checks more rigorously than the aviation industry and topdressing pilots are more safety conscious than most given the inherent dangers in their occupation, and still a wheel fell off! The biggest myth is that carrying out an HV (500V) insulation check on electronic appliances will blow them up. For any mains powered appliance, no matter what it is, be it a computer, medical or scientific instrument or what ever, applying 500 volts between phase and earth, phase and neutral or neutral and earth, will cause no harm at all. My favourite party trick to convince doubters is to apply 500 volts to my laptop in all connection combinations. In reality though, the test is performed by applying 500 volts between linked phase and neutral (with the mains switch on if mechanical) and earth. ElectroLink magazine published an article a few years back on insulation testing and a prize was offered to anybody who could show that any mains powered applianced could be damaged by a properly applied insulation test. The prize was never awarded because nobody could make the case. Oh yes, forgot to mention, my laptop is still going strong. Doubters: If you still think I'm wrong, reply and tell me why and how. Cheers Billy 8-{)	Billy T (70)
106903	2002-12-19 20:47:00	thx for that billy T. looks like it time for me to go get the cert. mind you i should have got it ages ago seeing as i've been in and out of the electrical industry so much ;-)	tweak'e (174)
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