wrote:

On Friday, 22 March 2019 12:13:07 UTC, Scott wrote:
On Fri, 22 Mar 2019 11:02:17 +0000, 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. 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
Wwon't be if any movement occurs. irenuts aren't gas tight. US
Welectrical 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. Also on terminations that cycle through a
larger temperature range, its not uncommon for terminal pressure to
loosen with time.

I never imagined my question would generate such a response :-)

I am tempted to change to a 30A block just for peace of mind, even
though I am sure the method I have used is fine :-( :-( :-( In
fact, I think I'll get my mate (who is a retired electrical engineer)
to carry out a full risk assessment.

If you put both cables in the full length of the connector rather than
folding each, a 15A connector is fine.


NT

May even be better than the 30A one if there is room in the latter for
the screw to separate the two wires and let them slip round the sides.

--

Roger Hayter