How many sockets have I fitted incorrectly?

[stillp]

My worry is more that when one looks at averts in the likes of screwfix for these products there is nothing warning about TN-S only it's only when one goes to likes of RS that one gets the information as to how they are to be used.

I suppose it's for the buyer to satisfy him/herself that the specification of a product meets their needs, and can't necessarily expect the adverts of a retailer to provide all of the necessary information.

It's the responsibility of the manufacturer to supply sufficient information for safe use.

 

[JohnW2]

It's the responsibility of the manufacturer to supply sufficient information for safe use.

Indeed - with the product, but I don't think they have any responsibility in relation to what Screwfix choose to put (or not put) in their adverts (which is what concerned eric), do they?

In any event, in this particular case, I don't think that the documents we are seeing actually detract from safe use - if anything they simply 'prohibit use' and therefore destroy MK's market! The version of the document I have says that the sockets are only suitable for use in "TN-S systems where the supply neutral is connected to the supply earth" (a situation which does not {or should not} exist - so the products cannot be used at all!) and that they are not suitable for 127V L-N supplies (which no-one is going to find!).

Kind Regards, John

 

[stillp]

Clearly Screwfix can't make the information available unless MK supply it to them. The MK data sheet seems to be nonsense, so they are failing in their responsibility.
I agree that they are effectively telling their customers that the product can't be used, but I don't think many purchasers would buy the product and then decide not to use it on the basis of the data sheet provided.

 

[viewer]

Oh well, here's my thought to get shot down:
It's a mis-translation/interpretation. The intended meaning is that the sockets cannot be used for IT networks where there is no connection to earth (all the other systems join E to N somewhere). A fault on, say, electrothermy equipment in an operating theatre would not trigger this RCD because there would be no imbalance L N. however, a dangerous voltage/current could (at least in theory) still flow through an operator/patient due to failure of the equipment. It's fine to use it on a TT system. Suspect the odd voltage restriction is also due to translation/interpretation errors and it means that it cannot be used on 2 or 3 phase supplies, only on single phase 230/240V systems.

 

[JohnW2]

Clearly Screwfix can't make the information available unless MK supply it to them.

Obviously true. However, eric's concern seemed to be that the Screwfix advert was not telling him what (he believed) MK were saying in their documentation (that the product was not suitable for use with TT systems).

The MK data sheet seems to be nonsense, so they are failing in their responsibility.

Yes, total nonense, in several respects! In common sense terms they might be failing in some 'responsibility' - but, as I said, I don't see anything in that documentation which could lead to unsafe use of the product. On the contrary, as we are agreed, it effectively says that the product cannot be used!

... but I don't think many purchasers would buy the product and then decide not to use it on the basis of the data sheet provided.

I'm not sure what you are saying here. If they do not take steps to satisfy themselves that the product is suitable for the intended use before they buy it, but then discover that the included MIs indicate that it is not suitable, is that not essentially 'their problem'?

Kind Regards, John

 

[JohnW2]

Oh well, here's my thought to get shot down: It's a mis-translation/interpretation. The intended meaning is that the sockets cannot be used for IT networks where there is no connection to earth (all the other systems join E to N somewhere). A fault on, say, electrothermy equipment in an operating theatre would not trigger this RCD because there would be no imbalance L N. however, a dangerous voltage/current could (at least in theory) still flow through an operator/patient due to failure of the equipment. It's fine to use it on a TT system. Suspect the odd voltage restriction is also due to translation/interpretation errors and it means that it cannot be used on 2 or 3 phase supplies, only on single phase 230/240V systems.

Who knows. It's just nonsense. Your guesses may be correct but, if they are, what they've written is dramatically different from what they were trying to say.

Although many MK products are probably manufactured 'overseas', I can but presume that the documentation is written in the UK, so literal 'translation' should not come into it. What we've been reading clearly was not written by (or even 'reviewed by') someone with any understanding of matters electrical!

I don't see why any RCD socket should not be used on a 2- or 3-phase supply. Regardless of the nature of the underlying supply type, a socket is simply supplied with an L and an N, and would detect any imbalance in the current in those two conductors arising because of a fault to earth, regardless of where earth potential 'stood' in relation to the potentials of L and N.

Kind Regards, John

 

[stillp]

ocumentation which could lead to unsafe use of the product. On the contrary, as we are agreed, it effectively says that the product cannot be used!

... but I don't think many purchasers would buy the product and then decide not to use it on the basis of the data sheet provided.

I'm not sure what you are saying here. If they do not take steps to satisfy themselves that the product is suitable for the intended use before they buy it, but then discover that the included MIs indicate that it is not suitable, is that not essentially 'their problem'?

Kind Regards, John

My point was that a purchaser of these devices is not going to return them when he reads the instructions, so he won't be put off by the nonsense. Yes, you could say that is the buyer's problem, but it shouldn't be!

 

[ericmark]

I like I would guess many others nip out to get what is required if I don't already have one in my junk box. The nearest is often the supplier be it Lidi, Aldi, Homebase or screwfix will depend on direction I travel next for such a cheap item.

OK if a load of work may go to an electrical supplier but if I want a double socket and there is a RCD or filter one in my junk box it will get fitted regardless to if it really needs RCD or filters. At least until next trip out.

Although aware of 20A limit to many double sockets I was unaware of the TN-S or 13A requirements for RCD and filtered sockets of MK manufacture so there is a good chance I have at some time fitted one in an inappropriate position.

When I make out minor works certificates I don't include make of the socket so looking at records it would not show where any were fitted.

I am sure there are many others that when they find there is an error could not trace where the produces were used. Same applies were there is a produce recall OK may know I bought one but were it went is something else.

With a product recall OK the manufacturer would not have realised at the time but here is something very different. To knock on a door and say "There has been a produce recall can I check the serial number of the part I fitted?" is OK but knock on a door and say "I never read the instructions and I may have used the wrong parts on the house can I check?" is a whole different scenario.

As to wrong information we may think it's wrong but MK would have to say it was wrong. It's no good guessing. And since as stated no dates on the paperwork the only way would be to adopt another brand name.

 

[JohnW2]

My point was that a purchaser of these devices is not going to return them when he reads the instructions, so he won't be put off by the nonsense. Yes, you could say that is the buyer's problem, but it shouldn't be!

Fair enough. The first step has surely got to be for someone who has a sufficient interest (it's many years since I have had any need to even think about using an SRCD, so it really doesn't matter to me), to contact MK and try to at least get to the bottom of the nonsense - and hopefully persuade them to change it into non-nonsense (and put a date on it!).

Kind Regards, John