Wire nuts

[<me9]

They were (quite effectively) used in my parents' house (originally wired in the 30s using lead sheathed 3/029). This was ripped out in the mid 60s and replaced with PVC and conventional JBs.

[Andy Wade]

And/or "scruits" (ISTR).

[Andrew Gabriel]

Yes, you and Owain are correct.

[Chip]

On 21 Apr 2006 05:54:41 -0700,it is alleged that "gordonpuk" spake thusly in uk.d-i-y:

Both are fine if used correctly. (IMO)

To those stating wirenuts are illegal... cite please? [not trolling, genuinely interested why/when/how they were banned]

[Edward W. Thompson]

I agree with you wire nuts are fine provided they are correctly installed. There are two types the twist on and the type that are a drilled brass boss with pinch screw with an external 'plastic cover' that screws over. The wire nut terminations should be housed in a steel 'junction' box. The crimp on type of connector is not a wire nut and is used for circuits such as telephone systems as they are here.

The critical comment by respondent that wire nuts are not 'airtight' I find puzzling. Of course they are not and neither are any normal electrical connections made by other means.

Why people consider wire nuts dangerous and cause fires I can't guess other than speculate they have no experience of using wire nuts. The suggestion by one respondent of using wire nuts on high power circuits gives an indication of lack of understanding of their use.

Most North American homes are wood framed and hence any electrical fault that is not contained in a suitable enclosure, is likely to cause a fire whereas in a brick built construction if would be a minor consequence.

[Guy King]

The message from Edward W. Thompson contains these words:

I suspect the important bit is that the pressure at the points of contact isn't high enough to preclude air getting in between the conductors which is a well known and serious problem. The conductor gets warm and oxidises nicely, leading to a higher impedance and so on.

A proper high pressure gas tight connection forces the conductors together hard enough so that they're deformed and no air can get between the mating faces. This stops the problem at source.

From the few wirenuts that I've met they couldn't possible achieve the sort of clamping pressure that a screw terminal in a junction box could and as a result lack the reliability.

[meow2222]

Its the traditional screwless twist connects that are the problem.

according to who, and why? Theyre routinely not here.

a gastight connection is the basic requirement for any safe durable electrical connection. If not gastight, the touching surfaces oxidise and connection R goes up, producing heat, sometimes way too much heat. Wire nuts can not reliably achieve this, our chocolate blocks can.

not at all.

NT