Just bought these... opinions.

[D4N1EL]

Hi,
Just bought these (see pics) from Lidl, £5 each.

Talking to a guy in work, who seems to think they are a must have for any home DIY. I did buy a socket tester from screw fix but if fell apart the first time I used it so I returned it.

Socket tester.
If live/neutral are wrong, would the device still work? Same question for if live/earth are wrong.

I agree it might be a good tool to have but I’ve managed this far with out one, but for £5 I thought it’s worth keeping in a draw.

Non contact voltage tester.
Does a house run on AC or DC? I assumed DC.

what are your opinions, worth having or cheap crap?

 

[flameport]

They will work for their intended purposes, which are fairly limited.

The socket tester will indicate faults as shown on the front - it will NOT be of any use for all of the other problems not listed, including a neutral/earth reversed. In some cases it may give misleading results.

The voltage tester will show the presence of AC voltage. It is NOT a suitable device for proving dead before working on a circuit.

Does a house run on AC or DC?

AC.

 

[Harry Bloomfield]

Does a house run on AC or DC? I assumed DC.

what are your opinions, worth having or cheap crap?

It's AC - DC you mostly find in batteries. The socket testers are not infallible, use with care. The none contact testers are handy - better known as a volt stick. Learn how to use it. They pick up the field from a live conductor, they cannot detect a live conductor which is screened by any metal.

You might be able to trace cables buried just below the surface of your wall plaster, if plastic channel has been used over the top, but not if metal channel has been used.

 

[JohnW2]

.... it will NOT be of any use for all of the other problems not listed, including a neutral/earth reversed.

Indeed - but, to be fair, very little will. Unless I'm missing something, no 'live' test would detect an N-E reversal, although an attempt to measure R1+R2 presumably would.

Of course, if the socket had the ('required', and increasing common) RCD protection, an N-E reversal would be immediately apparent if anyone tried to use the socket.

Talking of such thing, as a matter of interest, in those which measure loop impedance (the OP's one doesn't), how is that done, I wonder?

Kind Regards, John

 

[Harry Bloomfield]

Talking of such thing, as a matter of interest, in those which measure loop impedance (the OP's one doesn't), how is that done, I wonder?

Me too, it must use a really tiny current.

 

[D4N1EL]

In one of my work locations the sockets in the office I use has RCD switches on the sockets, are they becoming more in domestic set ups or is it RCD protected a different way?

 

[JohnW2]

In one of my work locations the sockets in the office I use has RCD switches on the sockets, are they becoming more in domestic set ups or is it RCD protected a different way?

It's a very inefficient and costly way of providing (the 'required') RCD protection for sockets. The usual and sensible approach (everywhere, not just domestic) is to have the entire circuit protected by an RCD in the CU (or whatever), hence protecting all the sockets on that circuit with just one device.

RCD sockets only really make sense ('temporarily') if one is adding a new socket (which 'must' have RCD protection) to an existing circuit which has no such protection (since there is not a retrospective requirement for 'existing sockets' to be RCD protected).

Kind Regards, John

 

[flameport]

RCD sockets make no sense at all, as the standard for them requires that they have upstream RCD protection.

 

[JohnW2]

RCD sockets make no sense at all, as the standard for them requires that they have upstream RCD protection.

Interesting. On the face of it, that requirement seems to make 'no sense at all', either - what is the reasoning and, indeed, if that's the case, what purpose are they meant to to serve?

What you say is presumably not very well know since we frequently see people being advised to use and RCD socket if they want to add a socket to a non-RCD-protected circuit.

Kind Regards, John

 

[EFLImpudence]

Also - does any one know of a similar regulation stating that an electrical safety device may only be used where it is not necessary?

How did the regulation come about?

Could it be due to a misprint or misunderstanding?

 

[Swwils]

Interesting. On the face of it, that requirement seems to make 'no sense at all', either - what is the reasoning and, indeed, if that's the case, what purpose are they meant to to serve?

What you say is presumably not very well know since we frequently see people being advised to use and RCD socket if they want to add a socket to a non-RCD-protected circuit.

Kind Regards, John

We have a large new building at work and most sockets are RCD sockets. I think this was a decision to save estates call outs to reset RCDs upstream and avoid downtime for end users on other equipment.

 

[JohnW2]

We have a large new building at work and most sockets are RCD sockets. I think this was a decision to save estates call outs to reset RCDs upstream and avoid downtime for end users on other equipment.

I suppose that makes some sense - but, if what flameport has said is correct, there might be a 'requirement' for another RCD upstream of the RCD sockets - which not only sounds (at least, to me) to be a bit crazy, but also would substantially undermine the thinking you describe!

Kind Regards, John

 

[flameport]

Scope from BS7288:2016
Fault protection (MCB/fuse) and additional protection (RCD) required upstream of the RCD socket outlet.
Not intended for isolation either.

That part is included in the preview at https://shop.bsigroup.com/ProductDetail/?pid=000000000030337151