Xmas lights . . RCD and Timer . . . . . . . . . .

[JohnW2]

I really don't ascribe to this view that such things are subject to democracy.

Do you mean "subscribe"? However, I know what you mean, and I don't think this is really a matter of 'democracy' - and certainly not comparable with a situation in which the majority got arithmetic wrong, or got the capital of a country wrong (Australia, and maybe even the US, could have a problem with that!) in which case they are incorrect in terms of facts, not technical terminolgy!

I don't know whether the technical definitions of ELV and LV have 'always' existed, but (except occasionally in the forums like this!) I don't think that the general public have ever been significantly exposed to the terms with their technical meanings. If electrical items were (and had been) all prominently labelled as "Extra Low Voltage" or "Low Voltage" (correct technical definitions), then they would have become accustomed to that terminology and most would have come to understand that terminology and use it correctly.

However, as I've said, I don't recall having seen any consumer products prominently labelled "ELV", and those which are labelled "Low Voltage" are usually ELV. Since the general public have not been educated about, or exposed to, correct usage of the technical terms, the 'common usage' has developed (I suspect a very long time ago) - and I have very little doubt that the majority of the population believe that "Low Voltage" essentially does not pose a hazard, whereas higher voltages do.

If some people think <50V is 'low voltage'; what do they think >50V is? Do they think they have high voltage fridges etc?

Roughly speaking, I would say 'yes'. They are interested only in two types of voltage - "mains voltage" (which they might call 'high voltage'), which they recognise as 'dangerous', and "low voltage", which they believe to be generally non-dangerous.

That they get it wrong is because they do not know; not because the definition is wrong.

No-one has suggested that the definitions are 'wrong'. Indeed, there is not really a sense in which a technical definition can be wrong, since bodies creating definitions can do so as they wish. However, I would say that, in the absence of a mass-education campaign and enforced labelling requirements, the definitions they have adopted are 'unfortunate' and, at least theoretically, potentially dangerous.

Kind Regards, John

 

[JohnW2]

A Coroner has been known to accept the definition in the Standard...

I have no reason not to believe you. Are you referring to a reference-able case that I could look at?

However, that doesn't alter the generality of what I said. I never suggested that all Courts would think/behave in the manner I mentioned.
Courts (judges) will vary in their opinions and judgments and, as I said, I suspect that much might depend upon what the judge him/herself had previously believed "Low Voltage" to mean. The same goes for Coroners, who are not necessarily even lawyers in a general sense. However, I still think it very possible that at least some judges (or Coroners) might (and judge) feel as I suggested.

Kind Regards, John

 

[EFLImpudence]

Do you mean "subscribe"?

May do. I couldn't make up my mind.

 

[JohnW2]

May do. I couldn't make up my mind.

I'm sure that is what you meant. To "subscribe" to a view means to agree with, or associate yourself with, that a view - which is what you intended. One "ascribes" something as being due to something else.

Kind Regards, John

 

[EFLImpudence]

Does "ascribe" not mean "give credit" - accredit?

 

[JohnW2]

Does "ascribe" not mean "give credit" - accredit?

Yes, but that ("this painting is ascribed to the artist XYZ") is a different meaning of the word ..... and presumably not the sense you intended?

Kind Regards, John

 

[EFLImpudence]

Oh ok. I'll subscribe then.

 

[JohnW2]

This is interesting. I've just noticed the definition of "Low Voltage" in the IEC 'dictionary;:

151-15-03

en
low voltage (1)
low tension (1)
LV (1), abbreviation

voltage having a value below a conventionally adopted limit
Note – For the distribution of AC electric power, the upper limit is generally accepted to be 1 000 V.

No mention of a lower limt - so maybe 12V is "Low Voltage" after all

Kind Rigards, John

 

[JohnW2]

Oh ok. I'll subscribe then.

Fair enough - but I presume that you mean that you won't/don't subscribe

Kind Regards, John

 

[EFLImpudence]

 

[333rocky333]

Back in the days of early LV lighting, the 14th regs definitition of LV
was

NORMALLY exceeding extra low voltage, but not exceeding 1000 volts.

The "normally" has since been dropped,
So what effect would the word have had, to me it suggests there was not a set lower limit

 

[JohnW2]

Back in the days of early LV lighting, the 14th regs definitition of LV
was .... NORMALLY exceeding extra low voltage, but not exceeding 1000 volts. .... The "normally" has since been dropped, So what effect would the word have had, to me it suggests there was not a set lower limit

Interesting.

As I said, the current IEC definition not only does not appear to specify a 'set lower limit' but actually makes no suggestion that there is a lower limit at all!

As I say repeatedly, if the industry and those who invented the usual LV/ELV definitions wanted the general public to use that terminology 'correctly', they should have undertaken a prominent and widespread 'education campaign' and also should have taken steps to have such labelling compulsory on all consumer products. As things are, if you stopped 100 (or however many) people on the street and asked them what "low voltage lighting" meant, I really do doubt that you would get many even roughly 'correct' answers!

Kind Regards, John

 

[stillp]

OTOH, you can search for uses of the term in IEC standards: http://std.iec.ch/terms/terms.nsf/SearchViewEN?SearchView&Query=field+terms_en="LOW+VOLTAGE"&SearchOrder=4&SearchWV=TRUE&SearchMax=0

I couldn't find a lower limit. Maybe some of us are getting confused because of the 50V lower limit of the Low Voltage Directive.

 

[333rocky333]

More important, could Winston be wrong

 

[EFLImpudence]

As things are, if you stopped 100 (or however many) people on the street and asked them what "low voltage lighting" meant, I really do doubt that you would get many even roughly 'correct' answers!

Is that relevant?

I obviously presume you think it is but -
as you have pointed out, asking in a shop for extra-low voltage bubs is just as imprecise.
You would not want anything other than 12V if that was what was meant.

It is likely only a problem on here because we have to ask what is meant.

Why aren't 12V lamps just plainly advertised and marked 12V?