2 4mm cables into one hole?

[securespark]

I HATE twisters! It should not be done with solid strand, but so many "old school" sparks never got out of the habit. Argggh! It's my pet-hate!!!!

 

[Softus]

OK, this is why I asked - to seek informed opinion.

I'm confused though - how do you go about twisting a solid core conductor?

 

[Adam_151]

You get your 2 2.5mm² conductors at the socket, strip them back and grip them both in pliers and twist

(not me though... I don't twist them either, not worth the effort for a negative gain!, makes it more likely that you'll end up with bare copper hanging out, work hardens the copper so makes thjem likely to snap... and annoys the **** out of anyone who separates them for testing/fault finding etc.)

I just put them in untwisted and give them a bit of a pull afterwards to make sure both are gripped properly

 

[Softus]

OK - I get that. I wasn't asking about twisting together the solid cores from different conductors, but the strands of a stranded conductor.

For example, the strands of each flex conductor before inserting into a lampholder terminal

 

[plugwash]

twisting flex is generally a good idea as its easy for all/most of the strands to miss the screw giving a very weak joint if you don't twist it. Tinning the end with solder after twisting is even better but probablly only worthwhile for particularlly awkward terminals or if you already have a hot soldering iron to hand. you can also get crimp on ferrules, theese commonly seen in ready wired plugs but generally you can only get one of them into a terminal that would hapilly take two or three flexes of that size without them.

for stranded fixed wiring cable i doubt it makes much difference as ths strands are much bigger.

 

[Adam_151]

I thought it was considered bad practice to tin conductors in screw terminals, becuase of 'cold flow' related issues causing it to loosen off over time?

 

[PeeBee]

I think the problem is that he is using a single socket outlet, which will be a little tight with two 4mm cables.

 

[dingbat]

Shouldn't make any difference. All sockets, single, twin, whatever, should be designed to be installed in any position on a conventional circuit.

 

[SUNRAY]

[quote
The plus side is that twisting can give better readings[/quote]

Err have I got it wrong...
Doesn't better readings mean that its better?
I usually twist [or ferrule] stranded wire because it reduces faults.

 

[ban-all-sheds]

The plus side is that twisting can give better readings

Err have I got it wrong...
Doesn't better readings mean that its better?
I usually twist [or ferrule] stranded wire because it reduces faults.

 

[Click-Sure]

B&Q bargain white moulded are Marbo I beleive. Thrown Marbo gear back at a customer more than once. I use MK if the job will stand it but only keep a stock of GET on the van, 4mm2 x2/x3, no issues.

 

[nozspark]

I used to work as a civvy for the RAF fixing avionic equipment...

There were several incidents that occurred due to twisted (tightened) stranded conductors which caused the poor joints, so we were not allowed to twist..

I know aeroplanes are an extreme environment, but those were the rules and they weren't made lightly..

 

[SUNRAY]

I used to work as a civvy for the RAF fixing avionic equipment...

There were several incidents that occurred due to twisted (tightened) stranded conductors which caused the poor joints, so we were not allowed to twist..

I know aeroplanes are an extreme environment, but those were the rules and they weren't made lightly..

In my work which is mostly commercial controls the biggest fault BY FAR is failures where stranded wire has burnt out due to not enough strands being clamped. in domestic switches and sockets with a grub screw through a tubular hole if the wires are not twisted some of the strands can end up beside the screw and therefore not clamped and thats another maintenance visit.
In fact the previous quote says it all, wasnt that something like twisting can give better readings.......

 

[JohnD]

...stranded wire has burnt out due to not enough strands being clamped. in domestic switches and sockets

domestic stranded must be flex, unless you mean 1960's stranded imperial cable

But what are they doing putting flex into sockets and switches?

 

[ban-all-sheds]

In my work which is mostly commercial controls the biggest fault BY FAR is failures where stranded wire has burnt out due to not enough strands being clamped. in domestic switches and sockets with a grub screw through a tubular hole if the wires are not twisted some of the strands can end up beside the screw and therefore not clamped and thats another maintenance visit.

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