make this safe?

[333rocky333]

I probably wouldn't even bother to strip the conductors - I would probably simply tighten the screws onto their insulation!

Bit reckless John

What if in the future it was live and someone stuck there probes only on the brass terminals and assumed it was Dead

Also surely a MF terminal is not just for a connection but also to stop any wire coming adrift

 

[JohnW2]

Bit reckless John What if in the future it was live and someone stuck there probes only on the brass terminals and assumed it was Dead

Not impossible, I suppose, although I don't think I'd loose any sleep over that possibility. In truth, I suppose I probably would strip the conductors, but I was trying to emphasise that no 'electrical connection' was involved.

Also surely a MF terminal is not just for a connection but also to stop any wire coming adrift

That's what 'strain relief' is for. Are you suggesting that (although they have it) 'MF' JBs don't need to have strain relief?

Kind Regards, John

 

[sparkwright]

A live conductor(s) on it's own, terminated in a screw terminal in a junction box can just as easily go wrong as two or more conductors in a screw terminal that actually powers something.

Should we worry about a loose connection on a live wire that doesn't actually serve anything?

 

[JohnW2]

A live conductor(s) on it's own, terminated in a screw terminal in a junction box can just as easily go wrong as two or more conductors in a screw terminal that actually powers something.

What do you mean by 'go wrong'? All that can happen is that it comes out of the terminal, and 'strain relief' should prevent that.

Should we worry about a loose connection on a live wire that doesn't actually serve anything?

See above.

Kind Regards, John

 

[sparkwright]

It can 'come out of it's terminal' by other means than lack of strain relief. Simply not tightening it is enough. Or if the wire is poorly prepared, such as a tiny wire in a large terminal, and making a poor contact.

Also wires can snap off when over-tightened or if the end is not doubled over in a large terminal.

 

[JohnW2]

It can 'come out of it's terminal' by other means than lack of strain relief. Simply not tightening it is enough.

If strain relief is inadequate, it should not be able to come out even if the terminal screw is very loose, should it?

Also wires can snap off when over-tightened or if the end is not doubled over in a large terminal.

True, but I'm not sure what point you are trying to make, in either this or the preceding post.

In any event, is this not all a bit silly? In reality, if the JB is 'inaccessible' it is incredibly unlikley that anything would cause a conductor to come out of a terminal, even if there were no strain relief and the terminal screw was loose, wouldn't it?

Kind Regards, John

 

[sparkwright]

I imagine the bad connection would be there at the moment the wire was put in the terminal. It has been known for a wire to be tightened into a terminal, only for the wire to snap a few seconds or so after. I'm a great believer of doubling ends over to give strength to wires that are prone to snapping.

I just don't like the idea of a live wire (on it's own) just barely touching the terminal it's supposed to be connected to.

That said, I wouldn't worry about a screw terminal junction box being used under a floor to terminate one live cable, if I was satisfied I'd done a reasonable job.

 

[JohnW2]

I just don't like the idea of a live wire (on it's own) just barely touching the terminal it's supposed to be connected to.

In the situation we're discussing, it's not supposed to be 'electrically connected' to anything. The only reason for inserting it into a terminal at all is to keep it in place (away from other conductors) and, particularly if there is also strain relief, the terminal doesn't have to be all that tight - so minimal risk of snapping the conductor.

That said, I wouldn't worry about a screw terminal junction box being used under a floor to terminate one live cable, if I was satisfied I'd done a reasonable job.

Quite so. This discussion really does seem to be a bit OTT. I imagine that, in practice, most people would just use 'any old JB', probably without any strain relief, and not tighten the screws excessively, and then never give a second thought to what they had done.

Kind Regards, John

 

[markyyyyyy]

thanks for the input people. I've gone and bought a JB as per link above so i'll just put them in there. does it actually matter which terminal it is connected to? as it's terminating not actually connecting.

 

[sparkwright]

UNLESS the terminals are labelled, it shouldn't make any difference which terminals you use.

You will most likely need to cut the wire ends off and re-strip, to ensure a sound connection.

Also ensure the outer sheatn of the cable enters the junction box.