More dodgy tat

[SimonH2]

Got a call from my mate a couple of weeks ago, he's got some new roses he wants put up. In a couple of rooms, the roses have been dangling on the cable for a while since the ceiling was skimmed - waiting on new fittings.

Fair enough - simple job, looped at switch, just 3 wires to connect.

So here's the fitting he handed me - I guess the "flex" will straighten in time

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• SimonH2
• 16 Jan 2015
• 1

So what's the first thing I notice - yup, no earthing for the metalwork. That's because it's, according to the labels, double insulated. Yeah right.

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• SimonH2
• 16 Jan 2015
• 1

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• SimonH2
• 16 Jan 2015
• 1

Me thinks, and says, something to the effect that someone's 'avvin a larf.
That metal can isn't DI, the lampholder itself might just about be (that's a metal cap over the lampholder, mounted on a metal bush)

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• SimonH2
• 16 Jan 2015
• 1

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• SimonH2
• 16 Jan 2015
• 1

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• SimonH2
• 16 Jan 2015
• 1

Then I find that it did come with destructions which explain it all

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• SimonH2
• 16 Jan 2015
• 1

In case you can't read it, it says : Always cover the terminal block with at least two layers of insulating tape to isolate it from the fitting
So that's all right then

Also in the pack were two small bits of sleeving (braided, feels a bit like glass fibre) - although not mentioned in the instructions :

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• SimonH2
• 16 Jan 2015
• 1

So I did my best, I used a small piece of wire, looped under one of the mounting screws, to earth (as best I could) the metalwork, wrapped the block with tape, and put the sleeves on the L&N of the T&E which is what I assume they are provided for.

The more eagle eyed may have noticed the description of a lighting circuit near the top of the destructions

BTW - while these were (I think) 'eBay specials', they were in fact from a UK electrical supplier, with a UK address.


Then onto job no 2 - just drop a coax down from the attic and connect the new Freeview receiver to his new monitor. No problem apart from him having misplaced the splitter that I know he did buy. Connected everything up, but what's this : 2 pin PSU with an adapter :

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• SimonH2
• 16 Jan 2015
• 1

Yup, you guessed it, 'eBay special', unfused adapter. For good measure, the Freeview box has Russian firmware and doesn't decode the EPG for the HD channels. What's more, watching something on BBC2 HD, and got subtitled for ITV HD - that was "quite confusing" to say the least until I recognised some dialogue from the program.
Still, it was cheap - what more could anyone want ?

 

[winston1]

For good measure, the Freeview box has Russian firmware and doesn't decode the EPG for the HD channels. What's more, watching something on BBC2 HD, and got subtitled for ITV HD - that was "quite confusing" to say the least until I recognised some dialogue from the program.
Still, it was cheap - what more could anyone want ?

So presumably not a Freeview box at all but a generic DVB-T/T2 box. So it won't decode digital text either.

To be called Freeview it has to conform to Freeview standards and have the "digital tick".

 

[SimonH2]

So presumably not a Freeview box at all but a generic DVB-T/T2 box.

Indeed, although it was described as Freeview IIRC

So it won't decode digital text either.

Never tried that !

But not my box, not my problem. Lets just say my attempts to educate my mate on the value of "value" vs "low price" haven't been too successful in most areas.

 

[ericmark]

Seen those adaptors before

of the three adaptors only one has a fuse. However in a 4 way extension with fuse in plug of extension they still do an good job. I have a few times wondered if I should glue them into the extension?

I could not see the point in freeview for the one or two extra channels I think Dave and Yesterday are free on DTV-t but not on DTV-s but I like films for men and not having to continually re-tune so given up on terrestrial TV.

As to lamp I have wondered many times about the double insulated symbol but if you earth and any thing goes wrong it's down to you if you don't it's down to supplier and manufacturer. I am not happy with earthing item designed to have no earth.

There are times when we have no option. I was given a mag mount drill to test and the drill was class II but the mag mount base was class I so since a metal gear box on the drill the drill ends up being earthed as well.

But with a drill with a metal gear box even though you could clearly drill through a live cable if the drill says class II that's what it is and I would not try connecting an earth wire to gear box. So in same way a light fitting with metal does not auto make it Class I like the drill it can be classed as class II and we are not the ones doing type testing so we have to do as we are told.

 

[JohnW2]

As to lamp I have wondered many times about the double insulated symbol but if you earth and any thing goes wrong it's down to you if you don't it's down to supplier and manufacturer. I am not happy with earthing item designed to have no earth.

Whilst I don't really see why one would want to do it (assuming thatone believed it really was up to Class II standards), I'm not sure that I really see the problem, either - other than the general undesirability of increasing the amount of earthed metal around the place for one to touch. If the item is described as Class II, then any exposed metal parts must be deemed to be comprehensively insulated from any electricity (hence 'floating'), so it really shouldn't matter what you do or don't connect to that metal.

So in same way a light fitting with metal does not auto make it Class I like the drill it can be classed as class II and we are not the ones doing type testing so we have to do as we are told.

As above, apart from the general fact that it increases the number of earthed things around (which is some situations can present hazards), just as would be the case if you decided to earth your (otherwise 'floating') metal bath (or even your fire-guard, door knobs or cutlery), I can't see what harm comes by earthing exposed metal parts of a Class II item, but maybe I'm missing something.

Kind Regards, John

 

[SimonH2]

I am not happy with earthing item designed to have no earth.

And I wasn't happy not earthing a lump of metalwork that (IMO) is DI in name only - seriously, two wraps of electricians tape == reliable insulation ?

In this case there's only the one T&E, and I've used the bits of sleeving they provided. I reckon few of them will ever be installed in a manner that maintains the DI. Think of all the wires/connections in a common "loop in and out via the rose" installation - there'll be single insulated live wires, and a random extra terminal. I can't see any reasonable person thinking that this fitting is going to be reliably kept DI in many installs - especially the usual "bin the destructions" (sometimes) DIY installs.

... if you don't it's down to supplier and manufacturer

While I don't think there's a lot of risk either way in this case, being able to point out it's someone else's fault isn't very helpful after someone gets hurt

 

[leeco]

The problem is ebay and sites like this.


You get it posted in a brown envelope or box that you have to pay import duty on it then you find out its junk.

 

[bernardgreen]

Hypothetical question.

A metal cased Class II ( double insulated ) fitting which manufacturer states "must not be earthed" had to be fitted to a piece of structural metal work which is connected to earth.

Does one obtain and fit a mounting kit that isolates the fitting from the structural metal work ?

Or does one ensure there is an RCD in the supply and allow the case to be "earthed" via the structural steel.

It may be that the manufacturers can see a situation where a failure in the double insulation would make the case live. If that happened and if the case was connected to "an earth wire " that was not earthed then all other metal work connected to that "earth wire" would become live.

 

[winston1]

Hypothetical question.

A metal cased Class II ( double insulated ) fitting which manufacturer states "must not be earthed" had to be fitted to a piece of structural metal work which is connected to earth.

Does one obtain and fit a mounting kit that isolates the fitting from the structural metal work ?

Or does one ensure there is an RCD in the supply and allow the case to be "earthed" via the structural steel.

It may be that the manufacturers can see a situation where a failure in the double insulation would make the case live. If that happened and if the case was connected to "an earth wire " that was not earthed then all other metal work connected to that "earth wire" would become live.

The manufacturer needs educating. There is a difference between "must not" and "needs not to be".
There is no reason not to earth class 2 equipment, just doesn't have to be. In fact I make sure my class 2 audio video equipment is earthed as the combined leakage currents of umpteen bits of gear can give a nasty twinge. Not nice at the top of an aluminium latter while adjusting a satellite dish.
The insulation failure and not earthed earth wire situation equally applies to class 1 equipment.

 

[DetlefSchmitz]

The manufacturer needs educating. There is a difference between "must not" and "needs not to be".

That was an intelligent point to have made.

This is a common translation error. e.g.

Er muss nicht gehen == he need not go. (not he must not go)

 

[bernardgreen]

Er darf nicht gehen = he must not go.

A common mix up as "muss" sounds so much like "must"

But manufacturers should know better and employ mother tongue translators.

 

[ban-all-sheds]

I have a German vacuum cleaner.

According to the instructions it is forbidden to run it over the edge of a loose carpet, it is forbidden to use it on wet floors, and so on.

 

[JohnW2]

The manufacturer needs educating. There is a difference between "must not" and "needs not to be".

That was an intelligent point to have made.

I agree.

This is a common translation error. e.g. Er muss nicht gehen == he need not go. (not he must not go)

Yes, that is probably the explanation in some cases. However, I'm pretty sure that I have seen instructions which say something along the lines of "...need not and must not..." - indicating that they really do mean the 'must not' (and well as 'need not') bit. I suspect that in a good few case we are simply talking about ignorance on the part of those who wrote the instructions.

Kind Regards, John

 

[EFLImpudence]

A metal cased Class II ( double insulated ) fitting which manufacturer states "must not be earthed" had to be fitted to a piece of structural metal work which is connected to earth.

Had to be?
Are you then not going against the manufacturers instruction and the principle of class 2 and the reason for it?

Does one obtain and fit a mounting kit that isolates the fitting from the structural metal work ?

I would say yes - or fit it somewhere else or use a class 1 product.
I agree that the end situation is the same so you do not need class 2 products.

Or does one ensure there is an RCD in the supply and allow the case to be "earthed" via the structural steel.

RCD is irrelevant. It should not be fitted there.

It may be that the manufacturers can see a situation where a failure in the double insulation would make the case live.

No. If properly class 2 the manufacturer ensures that the case will not become live.

If that happened

It won't.

and if the case was connected to "an earth wire " that was not earthed

Don't do it then.

then all other metal work connected to that "earth wire" would become live.

No. The case may become live because of a fault elsewhere.

 

[SimonH2]

I suspect that in a good few case we are simply talking about ignorance on the part of those who wrote the instructions.

The instructions are part of the equipment. So what does such ignorance say about the quality of engineering of the rest of the equipment ?