Consumer unit regulations change

Dec 12, 2014 124 Replies

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This quote is interesting.

******** 'A termination that is too loose can lead to arcing and hotspots, too tight and you risk damaging the component, as one manufacturer said to me we get many components returned with a deformed terminal cage cause by over tightening.' *********

Don't think I've ever come across a terminal cage with a screw fixing where that has happened. Most likely scenario is the head of the screw splits or the screw shears, or the thread strips. Different matter with those which need a spanner to tighten.

Other problem with any torque setting device is it needs regular checking for calibration. Especially something which is likely to be chucked into a tool box - and dropped regularly, etc.

It's rather like Kwikfit - be seen use a torque wrench and you can't be sued for a wheel coming off. But has anyone ever seen them check the torque wrench setting against a chart to make sure it is correct for that particular car?

I've seen a lot of burnt off terminations on my travels including quite a f ew in crimped joints but I cant recall any that caused fires. The cases of electrical fire that spring to mind include vastly overloaded flexible cabl es with bodged fuse replacement and heaters with combustibles being laid ov er them to dry. I discovered a Wylex consumer unit quite recently with a charred section of neutral bar and conductors that had a hole baked in the plastic casing abo ve the damaged section but no fire.

Hot terminals don't always catch fire, you get other faults first. Once a terminal is getting hot then the thermal cycling will loosen the screws much faster.

They always check them in my local tyre shop. They also know how to use a torque wrench.

They use the same chart to check the tyre pressure. Its a national tyres depot.

I know this. As an apprentice I installed lead sheathed cable. It was very easy to lay and clip nice and straight.

That would be an expensive business. No guarantee to find every joint box either. The answer is to have enclosures that are non-flammable/can contain any heat/fire that happens. With proper terminals. As once upon a time they were. Before all this cheap s**te came in.

I have, just the other day.

A bulkhead light from eBay, seemingly identical to Screwfix's, but 2/3 of the price. The terminal cage elongated and ovalled with very little effort, before the screw stripped - again, with very little effort. Very shonky s**te. Yet, in some details, it was slightly nicer than SF's equivalent - much bigger/better screws to hold the cover on.

In article , Robin scribeth thus

Wots wrong wiv tighten, shear of the bolt and then back of half a turn/>

Thats what me dad used to do with spitfire engines back in WW2, never had any complaints;)..

In article , harryagain scribeth thus

Bloody heck Harry!, if its anything lead sheathed now it'd be falling to bits when touched!!...

Or in you mind did they make lead sheathed PVC cables:?..

I regularly shorten extension leads at the plug end. The flex comes with bootlace ferrules fitted and the terminal screws are always lose due to the elasticity of the ferrules.

Refitting the plug without the ferrules using the time honoured way of twisting, and folding the conductor back on itself, before inserting it in the terminal makes for a sounder connection than the manufacturer achieved (IMHO)

No, it was rubber. Which might be OK in a suitable environment. Not very likely though. I have a rubber insulated extension lead that's thirty odd years old. Perfect condition, outlasted several plastic ones.

But lead sheathed cables must be a lot older than that - over 70 years old, at least.

No way would I trust that! IME (sample of 4, 2 at work and 2 local) electricians have no feeling for tightness (rather than do it up 'til it breaks). At work we had big chambers with a couple of hundred terminals ranging from octal bases up to 3-phase contacters and fridge motors. In the end I checked them myself - got fed up of trying to replace a component and finding half a screw-head missing. They seemed to do up /every/ screw, not just those that needed a tweak.

OOPS, makes no difference as to why not

If components and workmanship are substandard, isn't it the case that replacing a combustible enclosure with a conductive enclosure will not necessarily reduce deaths but change the cause from fire to electrocution?

In article , harryagain scribeth thus

Must be a very special rubber eh;)?....

If you Google, it's easy to find a chart of a maker's torque settings for wheel nuts. Ford, for example, go from 90 to 200 lb.ft depending on model

- with just about everything inbetween.

I've never, ever, seen this on a commercial extension lead.

I wouldn't expect you too as the ferrules make them less likely to work loose. Mainly due to the bit of springiness in them that keeps the pressure up.

Pond wiring is almost always in a rubber cable, it lasts longer and stays flexible. TRS, tough rubber sheathed.

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