ECN Forum Forums General Topics of the Trade Non-US Electrical Systems & Trades Hello from the U.K.

Paul, I was doing start up on a power plant with an engineer from the UK recently. When making up a small motor he commented on the wire nuts I was using. He said electricians back home would only us them for temporary situations and said he was supprised to see we use them everywhere. Have twist on wire nuts not gained general acceptance over there from what you have seen?
Nick

No, there's nothing in the I.E.E. Regs. to say earth should be at the top.

However, all of our 3-pin plugs are the type that I think you would refer to as right-angle caps, i.e. the cord emerges downward rather than outward, so any other orientaion seems awkward.

Another point is that the majority of our outlets fitted in homes have built-in switches mounted on the upper portion of the wall plate, so fitting outlets the "wrong" way would put the switches below the plugs and have them operating upside down (from the British point of view, that is!).

Very occasionally you might see sockets mounted sideways in a tight spot, and I have seen a couple upside down, but it's very rare.

By the way, our "twin" sockets (i.e. a duplex) are side by side instead of one above the other.

What proportion of U.S. receptacles would you say are fitted each way?

Nick:

Wire nuts are rare here. In fact many electrical suppliers don't carry them and requests for them will quite likely be met with a puzzled "What?"

I've seen them used for the internal splices in some light fittings (usually imported from the Far East), but that's about all.

As far as residential wiring is concerned, 99% is done in PVC-sheathed "twin & earth" (similar to Romex), and we have purpose built plastic junction boxes with brass screw terminals molded into the base.

Where an extra wire needs splicing behind an outlet or other accessory we use the "chocolate block" type screw connectors.

Do you know when wire nuts came into common use in the States?

Paul,

The majority of receptacles are with the grounding hole down. From my observations I would say maybe 95% of Residential receptacles are that way. Right-Angle plugs seem to be oriented that way.

Bill

It was way before my time. Maybe some of the "more experienced" (older) folks on this site could shed some light. Judging from existing work I have seen I would say the late 60's.
Nick

I think wirenuts came along about when I was a baby, in the early-mid '50s.
Paul,
I've never heard of a "chocolate block" connector. Could you describe one?
It's interesting that your boxes and receptacles are a unit, given the multitudes of component combinations we use here.

Hi guys,

I just had to jump in here. Really interesting reading about Britian's differences in wiring. Paul's description of his "box and receptacle in one" sounds a lot like the combination device/box used in the modular home industry here in the Midwest. They look like PVC remodel boxes with the flip up "wings" and an integral device molded into the box. Pain in the rear to repair, but they must be fast to install.

Dallas

Most of the fittings used for domestic work here are a combined switch/socket and faceplate. Single sockets come on a 1-gang plate abut 3.25 i. square, while a 2-gang is the same height but about 5.75 in. wide.

It's possible to buy 1, 2, or 3 switches in the 1-gang size, and up to 6 on the 2-gang.

The mounting boxes are separate: Most new work uses metal boxes which have knock-outs, but plastic boxes matching the accessories are available for surface mounting. Plasterboard boxes are comparatively new, and have twist-out lugs for wall mounting where there's no stud or noggin handy.

Modular fittings with separate accessories and cover plates are used as well, but they work out more expensive so tend to be used only in commercial applications.

I post some pics but I'm afraid I don't have a scanner.

If wire-nuts came into use sometime in the 1950s, then no prizes for guessing my next quetion. What was used before? Some other type of connector, or soldered and taped joints?

Electure:
The "chocolate block" connector. Imagine a small plated brass tube, about a half inch long. Wires are slid into the tube and two screws tapped through the wall at either end clamp the wires in place. The tube is enclosed by a plastic surround which has two round extensions to cover the heads of the screws. They are usually supplied in strips of 10 or 12 with th plastic molding linking hem together. You can cut off one, two, or as many as needed in one strip. Originally the plastic was dark brown (hence "chocolate block"), but these days most are a clear translucent plastic. The come in different sizes, like wire nuts.

Bill:
In Australia and New Zealand they use plugs which have 3 flat blades similar to those on U.S. plugs. Their outlets are oriented with the ground at the bottom.

Hi!
Have been following the discussion about the UK/US wiring methods (very interesting by the way). Since I’m Swedish, I have some trouble understanding everything that’s written. Especially technical names on different wiring material. So I have a question, what exactly is a wire-nut? In Sweden we have something called “Top-clamp” (directly translated from Swedish). It’s like a small plastic cone in witch you twist the wires together. Is that something similar to a wire-nut?