Are these acceptable today?

Ideally unused wired should be terminated to earth - however covered so as to prevent random contact is certainly better than being left flapping about, if not actually earthed.

Why not just terminate unused wires in wago connectors

Just looking for the cheapest solution.

PA

Just use extra Wagos?

They make Wago wiring centres for a neat central heating control box

I doubt it. My cost was 4p per terminated wire.

PA

Ah, so that is what they are called. There were plenty in our last,

Unused doesn't mean unpowered, John. For example one is one pole of the local zone valve switch. In the simplified circuit there is no feedback to the boiler from the zone valve. This released the bare copper wire's function, which is now performing as an earth conductor. Incidentally that 2+Cu's Cu was shielded with sleeving by the original installer. "Good Idea", I guess he said to himself. "After all it can be at 240v when the boiler is in use".

Good idea - except the sleeving he chose was green/yellow !!!

PA

Cheapest solution is a back box & terminal strip.

The ancient ones were ceramic.

I've a friend who refers to these things bandaged up with old cloth insulating tape as "Mummies" .

Brian

Would those nuts grip a single strand of wire?

My thought as well.

I've still got a few. "Screwits" is the name I learned. Worked well in the

Well, both of you, it depends upon what you mean by "single strand"...

But, whatever, some of us are bright enough to bend over the "strand" so that it lies alongside the wire's insulation - if necessary more than once - and use the appropriate "wire nut" size.

That's what some of us would do!

PA

Ah, you've jogged my memory. Yes, they were plastic in the valve motor that stopped. They were plastic - and seriously warped. No spiral spring inside them, either. Even in my 4p ones there is a spring!

PA

Yes, grimy white ceramic. Very suspect in terms of the long-term stability of the joint.

I'd still worry about them for jointing - although the 4p ones I've used are all fitted with a prominent spiral spring which really holds on when the wire is tugged - and I'm only using them as single-wire caps.

PA

I had a failed motorised valve. The wiring to the motor was by ceramic wire nuts . It failed.

I soldered it together and put heat shrink on. Its still going

These things?

My house in the US used these, or something very similar. But then it had knob-and-tube wiring and those polarised two-pin US sockets.

Yep. I got them (40 pieces) on TEMU. Good quality it seems and for less than the newly-announced price of a UK 1st Class Stamp.

Crazy World,

PA

Yes, those are "wire nuts", an alternate name here is "marettes" (local term).

There is a table of wire capacities for each colour. You *must* select the correct item and not put "small" wires in a "big" wire nut -- the wires will fall out! The wire is stranded. The strands must be twisted in the correct direction. Then, when the wire nut is rotated onto the ends of (say) three wires, the wires are jammed together, and the stranded you twisted up to make it compact, stays compact. You can practice your craft, then unscrew the nut and see what a mess is inside. Adjust initial conditions, until you get good at it.

When the wire nut is fully seated, the copper strands are under compression inside the metal spring part of the nut. There is a conical metal spring inside the plastic (insulated outer) wire nut.

Three of those right now, hold my carriage lamp controller to the mains wire from the house, inside the carriage pole. They sit there for years, without a problem, exposed to humid summer air. And the frigid cold of winter. Never seen any "conductivity" problems. The only part of the thing that doesn't work well, is the relay they used on the controller PCB, the contacts tend to weld shut (leaving the lamp on). This only happens after a power failure. so there's some kind of transient doing that. Nothing to do with the wire nuts. They can be used in spaces, where small boxes would not fit.

They are only available up to a certain size, and the gauge of two wires stuffed into the big one, defines the ampacity they are comfortable providing. Presumably at some point, carrying enough amps through a scheme like this, would not be a good idea. But for illumination wiring, they're sufficient.

These have been on the market for decades, and if there was a concern about failure modes, they would have been removed from the market.

You don't use those, if you have room for any kind of box. My central air is fastened with a box, from one wire set to another. I would not put the biggest wire nut on those wires, and sleep nights. That's what boxes are for.

Even screw-down fixtures are dangerous. Thermal walkout can reverse a screw and allow a wire to come loose. Solid wires should at least be shaped, so they stay put even when the screw walks out.

And anything involving compression, the spring constant can degrade with time, which is why the spring seems "stiffer" than is really necessary. That covers aging.

A typical usage of wire nuts, might be in the base of a pole lamp, where the cord to the lamp (secured inside the base by an Electricians Knot) is fastened to wire coming down the pole from the light socket. Cut the wires to different lengths, such that the wire nuts aren't right across from one another, and the ends can be fastened with wire nuts. Then, the wire "stuffed" into the base area and the plate affixed or whatever.

As another example, I have one of these fastened to a wooden base for use in the house (as a worklight). With those, when you open the base, each lamp socket offers two unterminated wires. There is just enough room inside the base of that thing, for two blue wire nuts and fastening to a third (incoming) pair. The incoming pair is secured with an Electricians Knot (as we were taught in "shop class" in grade school). This is back when schools accidentally taught useful things.