I bought a nice one. £8.09 0n ebay.
Class I or Class II ?
- Thread starter JohnW2
- Start date
Sponsored Links
No, not at all.
If those exposed-conductive parts are separated from live parts by basic insulation, and connected to the cpc, then it's Class I.
If those exposed-conductive-parts are separated from live parts by double or reinforced insulation, then it's Class II.
I fail to see the confusion.
No.
But your view seems to be fairly irrelevant, as it doesn't seem to agree with the definitions in the standards that the manufacturers are working to.
If they build an appliance, fully encased in plastic or wood(!), and they ensure that there is double or reinforced insulation between the live parts and YOU, then they are at liberty to certify that appliance as Class II, as per the relevant standards.
If you don't agree with that, that's up to you...
Well, there's the rub.
Not really Class I, not really Class II.
Maybe the standards need updating?
No, not assuming that at all.
However, in EFLImpudence's case, the posited lack of a cpc, and the double-square mark would be pretty hard to argue against.
Sponsored Links
As I also asked of EFLI, are you not confusing "metal exposed parts" (everyday meaning) with "exposed-conductive-parts" (as defined in BS 7671) ?
In particular, my understanding of the BS 7671 definition (which seems sensible) has been that what you talk of as "exposed-conductive-parts separated by double/re-inforced insulation from live parts" are not, actually, 'exposed-conductive-parts' per the BS 7671 definition. Am I wrong?
Kind Regards, John.
So, a brief summary:
John W2: you seem to think that only completely insulated items can be Class II. Anything with metal on it automatically becomes Class I.
EFLImpudence: you seem to think that only items that have some metal on, but are double or reinforced insulated, can be Class II. Anything that is completely insulated cannot be called Class II.
That's what I seem to have gleaned from the thread so far.
John W2: you seem to think that only completely insulated items can be Class II. Anything with metal on it automatically becomes Class I.
EFLImpudence: you seem to think that only items that have some metal on, but are double or reinforced insulated, can be Class II. Anything that is completely insulated cannot be called Class II.
That's what I seem to have gleaned from the thread so far.
EXACTLY. That is the whole point we have been debating, and the reason I started this thread. Despite all the assertions about what what is Class I and what is Class II, you have at long last agreed with me that the sort of things I'm talking about to not actually fulfill the definitions of either.
That was my only point in starting all this.
Kind Regards, John
Definitely NOT. I thought I had been very clear in saying that sticking bits of isolated metal on/around an item which would be Class II without the metal does not change the fact that it is still Class II.
If the 'outer metal' is in any way electrically connected to what is within the 'Class II insulation', then that metal becomes an "exposed-conductive-part" (BS 7671 definition) and the item becomes Class I.
Kind Regards, John.
OK, after another trawl through the IEE CoP In-service I&T, I found this:
Chapter 11.2 (Notes), page 60:
"If an appliance with double insulation or reinforced insulation throughout has provision for earthing, it is to be considered to be a Class I or Class 0I appliance."
Note: no further distinction is made as to if the earthing is protective or functional.
As our laptop charger doesn't satisfy the definition for Class 0I (damn good job too), then Class I it is.
Yes, you have gleaned correctly.
I could be wrong but that is what I deduce from the definitions.
Fair enough.
"Provision for earthing" what? If it is a totally insulated item, then (given that these 'Classes' are all about protecting 'outsiders' from risk of electric shock) it would seem pretty irrelevant as to whether or not anything from which an outsider was adequately insulated (i.e. to Class II standards) was 'earthed' or not. This is all very confusing!
Kind Regards, John
Again, from the IEE CoP:
Chapter 11.2, page 56
"Class II equipment may be insulation-encased or metal-encased.
Insulation-encased Class II. Equipment having a durable and substantially continuous electrical enclosure of insulating material that envelopes all conductive parts with the exception of small parts such as name plates, drill chucks, screws and rivets, which are insulated from live parts by insulation at least equivalent to reinforced insulation. The enclosure of an insulation-encased Class II appliance may for part or the whole of the supplementary insulation or reinforced insulation.
Metal-encased Class II. Class II equipment may have a substantially continuous metal enclosure with double or reinforced insulation used throughout."
Hence my comment about no further elaboration on the type of earthing.
Their outlook seems to be if there's an earth going in, it's Class I.
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
Sponsored Links
