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Earth funnies and phantom voltages on lighting circuit

It was much easier in the past, most if not all light fittings were ceiling rose and pendants which were all made of plastic, no earth required.
 
So the safer option, where there is doubt, is to connect them as a class 0?
Class 0 refers to equipment that is not "single fault safe", that is a single reasonably foreseeable fault could render the enclosure live in a way that will not be disconnected by protective devices, I'm pretty sure class 0 equipment is not supposed to be sold in the UK/EU.

Class 1 achieves "single fault safe" through the use of earthing.

Class 2 achieves "single fault safe" through "double or reinforced" insulation, and more broadly through taking steps to eliminate or at least massively reduce the possibility of faults that could lead to the exposed parts becoming live.

So the question is, if one either has a notionally class 2 device that they either suspect is not up to class 2 standards, or the installation conditions make it difficult to maintain those standards what should one do?

1. Do nothing, ignore the problem?
2. Convert the equipment, or at least part of it, to class 1 by adding an earth connection?
3. Refuse to install the equipment.

I would personally go for 2 but I can see why some people would be reluctant to go against manufacturers instructions.
 
It is thought that double-insulated is safer than having earthed items ...
I presume you mean that it is safer to have less (or no) touchable earthed items? If so, I agree - but that applies to anything (and not only 'electrical' things), not just to double-insulated electrical equipment.
therefore it would be better to have all double-insulated appliances and no earthed items in the home.
Again, if you're saying that it would be better to have no touchable earthed items in the home, then I would agree (but achieving that would often not be very easy).
You are free to disagree.
As above, if I have correctly interpreted what I think you were really meaning by what you wrote, then I don't disagree.
 
It was much easier in the past, most if not all light fittings were ceiling rose and pendants which were all made of plastic, no earth required.
That depends upon what 'past' you're talking about - ther was a time when a substantial proportion of electrical accessories were brass.
 
So the question is, if one either has a notionally class 2 device that they either suspect is not up to class 2 standards, or the installation conditions make it difficult to maintain those standards what should one do?
1. Do nothing, ignore the problem?
2. Convert the equipment, or at least part of it, to class 1 by adding an earth connection?
3. Refuse to install the equipment.
I would personally go for 2 but I can see why some people would be reluctant to go against manufacturers instructions.
Pragmatically, I would probably do the same but, as you say, some people would (understandably) be reluctant to do that in violation with (often 'strong') MIs which, as I recently said, seem to be unnecessary and misleading.

If I were feeling less pragmatic, I might be more inclined to go with (2) and then try to get something done about a product which, by implication, probably should not be legally available in UK.
 
Class 0 refers to equipment that is not "single fault safe", that is a single reasonably foreseeable fault could render the enclosure live in a way that will not be disconnected by protective devices, I'm pretty sure class 0 equipment is not supposed to be sold in the UK/EU.

Sorry, I mistyped that - I meant Class 1, but hit the 0 next to it in error. Now corrected!
 
I presume you mean that it is safer to have less (or no) touchable earthed items?
No - fewer (or no) touchable earthed items.

If so, I agree - but that applies to anything (and not only 'electrical' things), not just to double-insulated electrical equipment.
I did not have time to include everything.

Again, if you're saying that it would be better to have no touchable earthed items in the home, then I would agree (but achieving that would often not be very easy).
That is why it is not done.

As above, if I have correctly interpreted what I think you were really meaning by what you wrote, then I don't disagree.
I was really meaning what I wrote by what I wrote.
 
I cannot add to that - except to say that generally speaking people think earthing is a good thing; it is not; it is a necessary evil.
Whilst, as you know, I agree with the concept you are championing, I don't think that "necessary evil" is a fair description - "unfortunately necessary" or "necessary compromise" would probably be better.

Given that, for better or worse, countless millions of Class I items have been manufactured, sold and put into service, earthing is not 'evil' but, rather, a 'necessary compromise', given that, under the status quo, the benefits of having earthing outweigh the downsides - or, put differently, under the prevailing circumstances, earthing is 'less evil' than would be 'not earthing'.
 
No - fewer (or no) touchable earthed items.
You're probably never going to change my life-long habit of of often getting the grammar of less/fewer wrong but, that aside, I'm glad that you appear to agree with me!
I did not have time to include everything.
Fair enough, but you could saved some of your time by not including "double-insulated" in what you typed (thereby implying that the comment was specific to double-insulated electrical items), when what you were writing/implying would actually be true of any electrical item, not to mention pipework, radiators, metal window frames and cutlery etc. etc.!
That is why it is not done.
Are you merely agreeing with me that we do not avoid having any touchable earthed metal because it would be impractical to achieve that?
 
Just remembered, I installed kitchen hood extractor bought from SF in a rental flat had no earth. The vid below explains classes 0,1,2 and 3, also mentions hoods w/o earth.
 
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You're probably never going to change my life-long habit of of often getting the grammar of less/fewer wrong
I hope you get someone to proof-read any official documents.


It is very simple:

Fewer applies to plural items - not as many - and less applies to single items - not as much.

Fewer slices, less bread.
 
I hope you get someone to proof-read any official documents.
I sometimes do, although it's much more common for me to be proof-reading what others have written. However, the primary/crucial purpose of that is always to ensure that what is written is 'clear and unambiguous', rather than to identify 'incorrect' grammar or spelling. It's probably also the case that many of the people who read what I write (or whose writing I read) are no more correct in their grammar or spelling than am I!

An added complication is that much of what I write is read 'multi-nationally', particularly in the US and (the many) countries that tend to follow US 'English' spelling and grammar. That rather confuses the question of what should be regarded as 'correct'.
It is very simple:
Whilst there are situations in which it is 'simple', I don't think that it's always quite as straightforward as you imply.
Fewer applies to plural items - not as many - and less applies to single items - not as much. ... Fewer slices, less bread.
It's essentially a one-sided issue. "Fewer" always refers to 'counts', and "less" to quantitative things. You will rarely, if ever, see "fewer" being used other than in relation to counts, but very many people (hence, perhaps, 'common usage'?) often use "less" to encompass 'fewer counts' as well as 'as smaller quantity of'. The issue therefore only really relates to the use of "less", not of "fewer" (which is almost always used correctly, by any definition).

Interestingly, it is also 'one-sided' in another sense. Whilst, as you say, it's probably strictly the case that it is only 'correct' to say "fewer slices" or "less bread" (the converses being 'incorrect'), "more slices" and "more bread" are both 'correct'. I can think of no single word that would be an 'alternative' (a converse to "less") to the "more" in 'more bread' - the best one could do would be a messy phrase such as "a greater quantity of bread".

Whilst the definitions you mention are those one will commonly see, "less" can be and adverb as well as an adjective, and in that situation the concept of 'single items' does not exist (e.g. "less attractive" or "less conductive").

Another major apparent anomaly of those definitions is that most units of quantitative measures are (as dictionaries would seem to agree) seemingly 'plural' (e.g. Volts. Amps, Watts, Ohms, Lumens, Miles, Hours, Kilograms etc. etc.) - but would you really use "fewer" with all of them for that reason? I imagine that you probably would in some cases (e.g. "fewer miles") but would you do so for all of them (e.g. that one lamp had "fewer lumens output" than another) ?

It does seem to me to be verging on the 'pedantic' to regard, say, "less plant-life" as correct but "less plants" as incorrect.

Whatever, there seems to be considerable debate, even amongst academic linguists, as to when "less" should be regarded as 'correct', and there are certainly many situations in which 'common usage' flies dramatically in the face of what definitions such as you mention would indicate. An oft-quoted example can be seen in many large supermarkets (at least, in the UK), where one will commonly find one or more 'checkouts' labelled "Less than 10 items", "Ten items or less", or something like that (and I don't think I've ever seen 'fewer' in that context).

In any event, as I wrote, I think I'm far too old for there to be much prospect of my ever changing a life-long habit (shared by a large number of other people) of often using "less" to encompass the concept of 'a lower count' (i.e. "fewer"), even if you continue to try to bring that about! I do sometimes use "fewer" but, off the top of my head, I could not tell you whether there is anything identifiable about the particular situations to explain why I sometimes do that. The one thing of which I'm pretty certain is that if I were always to use the word "less", I don't think there would ever being any doubt about what I was saying.
 
And yet you keep getting it wrong.
As so often, that depends entirely on what one means by 'wrong'.

However, whatever it means, as I wrote, I'm far too old for you, or anyone else, to have much prospect of changing what is essentially a life-long habit of mine (and of countless other people).

However, you haven't answered any of the questions I asked. For example, would you really say that one piece of equipment consumed "fewer Watts" than another, or that IR measurement had shown that one circuit had "fewer Ohms" than another?
 

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