Are these 'twist-on' connectors still legal in Electronic Equipment?

['LIVEWIRE?']

The connectors cover joints between the mains lead, mains switch and transformer primary in a 1980s Mixer I'm in the process of servicing. The connections are soldered, then covered with these 'Twist-on' insulators.
Should I replace them with soldered, sleeved joints or leave them as they are? They are not accessible to the end user when the covers are back in place, though the bottom cover of the mixer, which is metal, is, at most 0.5" below the wires shown, which will be fastened in place with cable ties when the repair is finished.

[Mike Phelan]

You can still get these from CPC and other suppliers; the ones we used years ago were called "Scruits" and were ceramic.

Personally, I rarely relied upon them but prefer to solder the joins.

[hansomcommon]

Some Japanese printers use these connectors still so I would assume they are still legal for equipment where the end user cannot access them directly.

[Stylo N M]

Hi,

By the look of the photo there is ample room for them to be foldered round and just strap them together with a cable tie, and then use a further couple of ties further down the leads and just tuck them down the side of the transformer, that will keep them secure enough and a blob of evo-stick over the silicon and the screwbit they won't come off, thats what I would do.

Paul.

[richrussell]

They're incredibly common in the USA, and although I'm sure they must comply with some sort of safety standard, it always looks no better than twisting the wires together and wrapping insulating tape round the joint. I've seen several bits of equipment where there's been obvious arcing inside them due to the wires separating due to poor fitment. Solder and heatshrink looks neater too.

I agree with Paul though, if they appear secure then cable tying the wires somewhere so that there won't be any physical movement of the joint would be a good idea.

[G6Tanuki]

They're popular in the USA where they're known as "Wire nuts".

Scruit was indeed the name for them when they were sold in the UK: I remember as a kid being greatly amused by an electrician's catalog in which the porcelain ones were listed as "Porc. Scruits" which made me think of Pork Scratchings.

Available from Screwfix:

http://www.screwfix.com/p/ideal-twis...et-90pcs/28340

though I'd never be caught using them myself....

Modern ones have a plastic body and a "helical spiral" wire insert, the old ones are ceramic with a molded "helical spiral". Granddad had lots of the old ones, probably better for stranded wire. I think they are quite good, much better than simply twisting wires together.

As to legality British law tends to say thing like 'it must be safe' etc. without specifying what is 'safe', a good thing in many ways as it lets new technology to be incorporated easily. There is the 'Part P' electrical regulation these days which, as far as I can work out only allows qualified people to work on the difficult bits of household electrics. I am not allowed to work on mine that I put in 20 years ago, odd!

[GrimJosef]

Originally Posted by merlinmaxwell

... As to legality British law tends to say thing like 'it must be safe' etc. without specifying what is 'safe', a good thing in many ways ... There is the 'Part P' electrical regulation these days which, as far as I can work out only allows qualified people to work on the difficult bits of household electrics ...

These two facts go together. The thinking is that if the law is not going to prescribe in minute detail every single feature of what is and isn't safe (and it would be a huge job for the law to go into all that detail) then the best alternative is to restrict the work to people who are competent to do it. They should be able to make a reasonably reliable judgement about what is safe and what isn't. And if they're using third party components then they can check the manufacturers' data to see what safety claims are made there.

The legislators will also quite often refer to a 'standard' or a 'code of practice' which sits alongside the legislation and which illustrates one way of doing the work safely. If you've followed the standard/code then you will have a very strong defence if you should end up in court after an accident or a complaint. If you haven't followed the standard then you will have to show that what you did instead was still safe. It might be difficult to convince a court of that, especially if there has been an accident.

Cheers,

GJ

[AC/HL]

You can do most minor work, including like-for-like replacements. The main exclusions involve external work, water eg. bathrooms, and the Consumer Unit.
http://www.diyfixit.co.uk/safety-and...gulations.html

However, household electrical regulations are off topic here, we're discussing electronic equipment.

[Miguel Lopez]

I find regularly those connectors (the plastic version) on Chinese and Korean stuff: ceiling fans, table fans, electric cookers.

[Nickthedentist]

Couldn't they be replaced with a more reliable, crimp-on equivalent?

Like the others have implied, I'd prefer a good soldered joint, protected by a couple of layers of heat-shrink tubing, preferably the adhesive-lined type.

N.

[jonnybear]

They seem to work quite well as they do tighten the twisted wire joint quite considerable making a good mechanical joint that will not slacken, compared with a twisted wire tape joint, and chocolate connectors which can work loose.
John

[Miguel Lopez]

I think it is Mr. Cheap work.

For mass-produced stuff it should be more time saving to use those wire nuts than soldering, protect with heat-shrink tubing and then apply heat.

Also a less qualified person (so lower salary) can put the wire nuts.

[Ed_Dinning]

Hi Folks, there is a modern crimp equivalent to the Scruit in the "Faston " range although it uses a different crimping plier to the normal red, yellow blue type. For fairly obvious reasons it is known as a "nipple" crimp.

Ed

[dseymo1]

I recently purchased a bag of Scruits from CPC's 'bargain corner', with a view to temporary lash-ups. They may well still be available there very cheaply, if you have time to scroll through the interminable lists!

['LIVEWIRE?']

Just to restate a point I made in my first post, the wires are soldered together, and the 'Scruits' fitted over the top of the joints, then sealed on with wax. I've no idea whether the soldered joints, or the wax for that matter, are original, but there was an o/c connection to one of the leads to the transformer primary, so I'll no doubt resolder them all as a precaution.