2nd Jan 2019, 6:58 pm | #41 | ||
Pentode
Join Date: Sep 2018
Location: Devon, UK.
Posts: 152
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Re: Modifications to equipment earthing arrangements.
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2nd Jan 2019, 7:47 pm | #42 |
Rest in Peace
Join Date: Jun 2006
Location: Chard, South Somerset, UK.
Posts: 7,457
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Re: Modifications to equipment earthing arrangements.
If a person causes a change of ownership to a piece of electrical equipment which he / she knows is not as originally designed and tested for safety, but declares that fact to the new owner, is that original owner relieved of all responsibility - as regards electrical safety - if he/she declares that fact and also states that the new owner has the responsibility to have said item electrically safety tested?
Also, if the original owner is ignorant of whether the item is (or isn't) as originally designed etc., what bearing does that have on this matter? Moreover - in the event of litigation - surely the original owner can always plead "What changes? If there are any, they weren't made by me: when I acquired this item, those changes were made by someone else: someone unknown to me at the time of my initial acquisition of it?" Overall, in a phrase, "Where does the buck stop?" Al. |
2nd Jan 2019, 8:53 pm | #43 |
Nonode
Join Date: Jun 2010
Location: Spalding, Peterborough, Cambridgeshire, UK.
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Re: Modifications to equipment earthing arrangements.
A few years back, when asked, my local tax inspector defined business as "the intention to make a profit". He also said it was irrelevant whether you actually did!
Rob
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2nd Jan 2019, 9:03 pm | #44 |
Dekatron
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Location: Heckmondwike, West Yorkshire, UK.
Posts: 9,642
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Re: Modifications to equipment earthing arrangements.
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2nd Jan 2019, 9:09 pm | #45 |
Dekatron
Join Date: Nov 2011
Location: Surrey, UK.
Posts: 4,400
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Re: Modifications to equipment earthing arrangements.
I daresay that much of what has been discussed above in terms of ambiguity and case-by-case judgement helps to explain the widespread use of the term "spares or repair" in listings. Again, the seller might assume that it counts as absolution of future responsibility but there is sure to be precedent of it being taken to legal judgement.
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2nd Jan 2019, 9:39 pm | #46 |
Heptode
Join Date: Feb 2014
Location: Nottingham, UK.
Posts: 649
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Re: Modifications to equipment earthing arrangements.
With the concerns over the legal implications over any work done to older equipment, we may be tempted to 'leave it as it was' to deem it safe.
Recently, I came across a turntable made in the sixties by a highly regarded maker. It had no internal mains fuse (mains TT motor); the mains lead was a twin lead with no outer sheath - old style lighting flex; the mains plug had no sleeves on the L/N pins. The service manual showed no internal mains fuse fitted to the unit as it left the factory. I'm sure that most readers here would want to replace the mains cable/plug and the overall level of insulation would be raised. Adding an earth here would be clearly wrong. But if everything has to be returned to original, then the level of insulation would be compromised with old style twin flex! The danger is that if we do nothing so to speak, things could be made worse. But if work is done in a safe and competent manner, the repairer could still be liable. The problem is: how do we define 'safe' as this varies with legislation over time; and what exactly is 'competent' given the wide variation of scenarios of equipment/user/repairer? There are simply no straight answers on any of this. I've got to agree with Boater Sam's post above on all of this! SJM |
2nd Jan 2019, 9:43 pm | #47 |
Dekatron
Join Date: Nov 2003
Location: Heckmondwike, West Yorkshire, UK.
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Re: Modifications to equipment earthing arrangements.
As far as I know (which isn't that far, legally speaking) legal definitions are as tested in court, hence the sometimes quaint language and the preponderance of Barristers. Shall, for instance, has a very specific meaning. You wouldn't want to be on the other end!
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2nd Jan 2019, 9:56 pm | #48 | ||
Dekatron
Join Date: Oct 2003
Location: Croydon, Surrey, UK.
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Re: Modifications to equipment earthing arrangements.
Quote:
Quote:
With reference to the first question above, it's not really a modification. You are simply changing one three-core lead for another and as long as it is done correctly then the equipment has not been changed in any way. It could be argued that the equipment is safer since anyone changing the plug in the future will (should) know which colour goes where. What you couldn't do (if you passed the equipment on) is fit an old-style (all metal pin) plug on to either the new or old cable.
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2nd Jan 2019, 10:10 pm | #49 |
Hexode
Join Date: Jul 2010
Location: Royal Berkshire, UK.
Posts: 471
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Re: Modifications to equipment earthing arrangements.
How would the line 'at the time of testing' stand in court?
'You replaced a 2-core mains lead for a 3-core mains lead, earthed the chassis and yet, didn't install an internal fuse?' 'No m'lord, the set has survived 82 years without one and once the new mains lead was fitted, at the time of testing, the set 'met' or 'exceeded' manufacturers specification. As a suitably qualified and experienced person '... etc. Then of course you have the conundrum of, 'except where no manufacturers specification for safety exists' in-which case, based on your experience, becomes 'best endeavors'. We know a vintage radio or television could never hope to meet today's safety requirements, by making changes, improvements/modifications whilst repairing/restoring, we're turning (quite possibly) dangerous/unusable items, into items 'fit for purpose'. Hmmm. Mark
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2nd Jan 2019, 10:29 pm | #50 |
Dekatron
Join Date: Aug 2016
Location: Colchester, Essex, UK.
Posts: 4,108
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Re: Modifications to equipment earthing arrangements.
If i adhered to every single law of the land, i would be doing two hours practice with a longbow per week. Just saying...
When i was in financial services it was always more important to understand which breaches of the data protection act would cause problems, and which aspects of it had to be breached in order to do my job properly. Put another way, adherence to the spirit of the DPA was vital- adherence to (all of) it's rules was nigh on impossible and would have reduced productivity unacceptably. The Dambusters quote might apply, we did have some fools- easily identifiable by the noise level. Dave |
3rd Jan 2019, 7:55 pm | #51 |
Octode
Join Date: Jul 2004
Location: Dundee, UK.
Posts: 1,813
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Re: Modifications to equipment earthing arrangements.
Most of the equipment of concern to forum members will be covered by some edition of British Standard BS415 "Specification for safety requirements for mains-operated electronic and related apparatus for household and similar general use", which, as far as I can determine was first issued in 1931, withdrawn in 1990 and replaced by BS EN 60065:1994.
I would be in interested to know what, if any, safety standards applied before that. I would not be surprised to know that electrical safety was largely undefined and considered to be "common sense" - a term which I beleive is not popular with modern safety authorities, possibly because it takes knowledge and experience to acquire common sense. If you would like to know what BS415 had to say at the time of manufacture of any of your equipment, their website implies that BSI will sell you a copy of any version for £176.00. The 1931 edition has 20 pages. PMM |
3rd Jan 2019, 10:50 pm | #52 |
Dekatron
Join Date: May 2010
Location: Greater Manchester, UK.
Posts: 18,724
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Re: Modifications to equipment earthing arrangements.
Would a trader be safe selling vintage equipment "For display purposes only" and getting a signed disclaimer from the buyer to that effect?
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4th Jan 2019, 9:47 am | #53 |
Dekatron
Join Date: Sep 2007
Location: Oxfordshire, UK.
Posts: 4,311
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Re: Modifications to equipment earthing arrangements.
I believe the regulations say that in that case the seller has to have reasonable grounds to be confident that the buyer will never use the set for anything other than display. Courts spend quite a lot of their time deciding whether people have behaved 'reasonably'.
Equally, if you snip the plug off a set and sell it 'for spares or repair' but you know there's a chance that the buyer will put another plug back on and plug it in then the court will assume that you were trying to wriggle out of your responsibilities. Courts tend not to come down too hard on people who make honest mistakes. But they really don't like people who try to get round the law by some tissue-thin trickery. Cheers, GJ
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4th Jan 2019, 2:25 pm | #54 | |
Triode
Join Date: Feb 2011
Location: Southampton, Hampshire, UK.
Posts: 46
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Re: Modifications to equipment earthing arrangements.
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So:
The law is generally very concerned with intent and what is reasonable. If you make a change with the intent and the reasonable belief that it will reduce the hazard associated with a device, and you are neither recklessly ignorant of what you're doing nor intentionally doing something you know to be hazardous, then you are unlikely to have legal problems in practice. The exception might be if you now claim that the resulting thing is "safe" or "as safe as a modern one" when it is instead merely "safer than it was", and thereby encourage someone to use a device that they might previously have thought too dangerous. Certainly for things like fixed electrical installations, and many areas in industry the "I made these changes which reduce the hazards, it is now safer than it was before" argument is well-used and accepted. Lets say you do add an earth connection to a class 0 heater which also has a poorly guarded element, and you sell that heater. I assume people are worried that if someone kills themselves by touching the element they will then be liable? You may have to make the argument in court that 1) the change you made did not affect the hazard associated with that part, and 2) that it was a reasonable thing to do because it reduced other hazards (loose wires inside making the case live), and potentially 3) that you didn't assure the customer that it was now safe for little johnny to play with. It is of course possible to spend a lot of time and money tied up in court trying to prove you are right, and understandably some people want to avoid that. There is also a non-zero risk of the court deciding against you, and it is reasonable to want to avoid that too. But for me personally, I am happy to take responsibility for a change that can only improve safety, and I will argue that in court if it ever becomes necessary. Morally, I would feel more comfortable selling something that has been modified to reduce the reducible risks than something that has not been modified at all. |
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4th Jan 2019, 3:48 pm | #55 |
Octode
Join Date: Dec 2008
Location: Wincanton, Somerset, UK.
Posts: 1,784
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Re: Modifications to equipment earthing arrangements.
Very well summarised, Richard.
John |
4th Jan 2019, 4:35 pm | #56 |
Nonode
Join Date: Nov 2016
Location: Aberaeron, Ceredigion, Wales, UK.
Posts: 2,887
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Re: Modifications to equipment earthing arrangements.
Yes I agree it makes sense, particularly the part about earthing, and making it “safer” but not necessarily “safe”.
Cheers John |
4th Jan 2019, 8:35 pm | #57 |
Nonode
Join Date: Mar 2010
Location: Sunderland, Tyne and Wear, UK.
Posts: 2,476
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Re: Modifications to equipment earthing arrangements.
Been trying to stay out of this discussion so far
If you modify equipment you are accepting the design/redesign. You basically have no idea what the original design criteria involved, or to which standard you are redesigning to or from, if we did we would not likely be the one to replace say a 2 core to a 3 core flex! It has been said that the road to hell was paved by good intentions and so it will. The "Earth everything brigade" are often misinterpreting partial (or even full) understanding/misunderstanding of other standards, some equipment may never be able to be brought up to current standards either. For example the manufacture may have originally designed a piece of equipment with certain clearances and/or specified components, certain IP ratings etc..etc. Now a well intentioned restorer or repairer may have "upgraded the original 2 core flex to a 2 core and earthed flex, seems reasonable to the person doing this right?, not so! the well intentioned person may have inadvertently introduced an unexpected or even intentionally avoided Potential difference or hazard where none was ever intended to be, which in fact may have even been designed out to the original standards the item was made to. This seemingly simple act will in fact negate any and all precautions the original manufacturer put in place to begin with. Now I am not saying all manufacturers were "snow white" or that previous standards are perfect by any means, or that design mistakes are never made, far from it!, the point being is that if you alter anything associated with safety then it had better be up to current safety standards. How many of us can say they are fully conversant with current safety standards as applied to consumer goods? not many I would wager. How many of us are fully trained experts in law ? again not many.
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4th Jan 2019, 9:22 pm | #58 |
Rest in Peace
Join Date: Apr 2008
Location: London, UK.
Posts: 2,508
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Re: Modifications to equipment earthing arrangements.
While some design decisions in consumer products were made to form a cohesive safety system, many more were made for economy. An earth connection, or an insulating barrier, or a double-wound transformer may have been seen as desirable by the engineers, but prohibited by the bean-counters as needless expense if the product could be marketed without it.
Therefore, adding such a connection, barrier or whatever, far from defeating all the existing safety measures, may go some way to achieving the level of safety the designer originally desired. Sufficient skill and knowledge are required when undertaking modifications, to decide which of these outcomes will occur, as Richard.CS summarised rather well above. |
4th Jan 2019, 9:30 pm | #59 |
Nonode
Join Date: Mar 2010
Location: Sunderland, Tyne and Wear, UK.
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Re: Modifications to equipment earthing arrangements.
I was not doubting that Lucien, but would you know that for certain ? I know I could not.
Now I know you from elsewhere I know you are clued up, but you know yourself particularly where the "bond it all brigade" (electrical circles) have often introduced a hazard where otherwise none previously existed.
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4th Jan 2019, 9:47 pm | #60 |
Rest in Peace
Join Date: Apr 2008
Location: London, UK.
Posts: 2,508
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Re: Modifications to equipment earthing arrangements.
I think the 'elsewhere' R2B is referring to concerns vintage electrical generating plant. In that domain, there is a significant risk associated with earthing things that were not intended to be earthed, because it can result in an IT (floating) supply being changed to a TN (earth-referenced neutral) supply. Absent the necessary measures to prevent direct contact, earthing can add new hazards without removing any existing ones.
That particular class of hazard does not generally apply to radios and TVs powered from the public supply mains, because the nature of the supply is imposed on the user by the supplier (all normal mains supplies are TN) and the presence of the earth reference is unavoidable. ADS is therefore the conventional means of minimising shock risk, and any alterations that improve the performance of ADS, such as improved earthing, are likely to reduce existing hazards without adding new ones. The exception to this - appliances used outside the equipotential zone and/or held in the hand during use - are alluded to above. Here again, sufficient knowledge is required to identify these special cases. |