On Friday, 22 March 2019 22:33:45 UTC, John Rumm wrote:
On 22/03/2019 15:17, tabbypurr wrote:
On Friday, 22 March 2019 11:02:19 UTC, John Rumm wrote:
On 22/03/2019 01:26, tabbypurr wrote:
On Thursday, 21 March 2019 16:41:09 UTC, dennis@home wrote:
On 21/03/2019 16:12, tabbypurr wrote:
On Thursday, 21 March 2019 12:53:00 UTC, dennis@home wrote:
On 20/03/2019 19:39, ARW wrote:
On 20/03/2019 18:11, Scott wrote:

I discovered a problem with a join in a ring main and decided to
replace the faulty connector with a terminal block.Â* I wondered if
this needs to be rated at 30A to correspond with the fuse (RCBO) or if
15A would be okay on the basis that it is a ring and some of the
current will go each way round.

On the Brunel principle I am fitting 30A but I am curious to know.


https://www.youtube.com/watch?v=2uYD8e7idnY


The video shows that the connectors will carry the current when new.
But what happens after they have had a few thermal cycles?
I would think the wire nut and the choc block will fail first.

Choc block & crimp are gas-tight, so should last.
Wago might be gas tight if the wire is never moved, it certainly won't be if any movement occurs.
Wirenuts aren't gas tight. US electrical fires are a testament to that.


NT


choc block are not gas tight.

yes they are. You're free to go & learn something.

That does rather depend on if there was adequate screw pressure created
when the termination was made.

obviously

Its not always easy to judge though since it depends on the area of the
screw "point". Some older fittings had quite large diameter screws that
needed lots more pressure to bite into the copper and form a gas tight
seal.

I figure if you're biting into the copper it should be gas-tight.


Also on terminations that cycle through a
larger temperature range, its not uncommon for terminal pressure to
loosen with time.

occasional loosening is their one weakness. I trust them far more than wirenuts or sprung pushins though.

Don't think I have ever met a real wirenut in fixed wiring applications....

I've seen some right horrors. Wirenuts in fixed wiring only seldom. One prize winner candidate was a factory floor full of industrial sewing machines all powered by wires strung overhead. Only just overhead, any random scrap of any old wire, joined by twisting the ends together, not even insulting tape. No earth in sight, no support for the wires anywhere other than at the ends. How the forces on the wires didn't pull the twist joints apart & bring live wires down on people's heads I don't know. Maybe the 'electrician' was a master in knots.


NT