10 mm cable joimt

[pete01]

Late to the party, but definitely 10mm through crimps.

 

[plugwash]

In contrast, we have a lot more than 50 years experience of traditional screwed terminals being in long-term ervice, and the design of those have changed little over the decades.

I've noticed there are certainly different types of screw terminal and I'm pretty sure which are most common have changed over the years.

* Round hole, direct bearing screw (some terminal block, many switches and sockets particularly older ones).
* Round hole with shield plate (some terminal block).
* Rectangular hole, direct bearing screw (common on more modern wiring accessories.
* Rectangular hole with shield plate (mostly seen this on PCB terminals).
* Square hole, with rising clamp (common on din rail mount switchgear).
* Shaped hole, with rising clamp (only seen this on pheonix contact din-rail terminals)

And has been said, there has also been a shift in materials, with plated steel becoming more common as it's cheaper than copper based alloys.

 

[Harry Bloomfield]

Can I just add? making the conductors size as near as possible to the terminal inside diameters to assist area of contact with terminals or other conductors too?

Back in the day of really large cables, and solder lugs. the rule was to always fill the space in the lug, with copper - binding the cable, if necessary, by winding a bare strand of copper around, to make up any gap.

 

[Harry Bloomfield]

And has been said, there has also been a shift in materials, with plated steel becoming more common as it's cheaper than copper based alloys.

A bad move, IMHO. Any terminal, in a less than perfectly dry location (doesn't have to be subjected to wet), will eventually begin to rust, despite the plating. The oxidisation/rust, then leads to high resistance terminations.

 

[Harry Bloomfield]

As suggested in my post #8

Well almost, but just suggests connectors with screw terminals, not how best to use them - as I expanded on.

 

[JohnW2]

I've noticed there are certainly different types of screw terminal and I'm pretty sure which are most common have changed over the years.

* Round hole, direct bearing screw (some terminal block, many switches and sockets particularly older ones).
* Round hole with shield plate (some terminal block).
* Rectangular hole, direct bearing screw (common on more modern wiring accessories.
* Rectangular hole with shield plate (mostly seen this on PCB terminals).
* Square hole, with rising clamp (common on din rail mount switchgear).
* Shaped hole, with rising clamp (only seen this on pheonix contact din-rail terminals)

And has been said, there has also been a shift in materials, with plated steel becoming more common as it's cheaper than copper based alloys.

You're talking about screwed terminals in general, but in terms of the bog standard 5A, 20A & 30A JBs, millions of which have been under floorboards and in roof spaces for decades, I don't think there has ever been any significant change in design -other than perhaps a change in materials (I confess that I thought they were all still brass), has there ?

To the best of my knowledge, those JBs have always had what is essentially a 'rectangular' hole (the screw screwing into a threaded hole in a limb of brass with slots down the side), and with no 'shield plates or 'rising clamps'. Is that not the case?

 

[plugwash]

To the best of my knowledge, those JBs have always had what is essentially a 'rectangular' hole (the screw screwing into a threaded hole in a limb of brass with slots down the side), and with no 'shield plates or 'rising clamps'. Is that not the case?

Yeah, those have been around for donkeys years basically unchanged. I don't think i've ever seen them in a size greater than 30A though.

TLC sell a 60A junction box, which has a design reminiscent of the terminals in old (pre din rail) consumer units. Probabbly a pretty good option for joining large cables in some circumstances.

 

[JohnW2]

Yeah, those have been around for donkeys years basically unchanged. I don't think i've ever seen them in a size greater than 30A though.

Indeed. It is they, which in many cases have been satisfactorily 'under floorboards' for decades which we are now told should be replaced with ('spring loaded'( "MF" ones, the experience of which is domestic installations is very much shorter.

TLC sell a 60A junction box, which has a design reminiscent of the terminals in old (pre din rail) consumer units. Probabbly a pretty good option for joining large cables in some circumstances.

They do - and I have some of them in the 16mm² and 25mm² distribution circuits in my house.