On 07/05/2019 21:34, Andrew Gabriel wrote:
On 07/05/2019 12:43, dennis@home wrote:
On 07/05/2019 07:52, Brian Gaff wrote:
I'd be a little perturbed that CUs were even made that easily caught
fire at
any time in history myself. Seems a little counter intuitive to me.
Â* Brian


They don't easily catch fire.
They catch fire more since the requirement to fit active bits like
RCDs as they are more likely to overheat than a plain fuse.

The cause of catching fire was entirely poor workmanship by electricians
- not doing up the terminal screws tightly enough (or at all in some
cases). It was well researched, because it started becoming a
significant problem in new installations. It wasn't failure or ageing of
any of the internal components.


It's now on the 18th edition EICRs that the person doing the testing has
to check the tightness of the bus bar connections and check that the bus
bar to the bottom of the MCBs is actually inside the MCB clamp.

Here is one I found last year.

http://wiki.diyfaq.org.uk/images/8/8d/EICRMCB.jpg

Of course it well worth mentioning that this can only happen with some
CU manufacturers.

--
Adam