Totally stumped about a tripping RCD!!

marconi · Oct 6, 2017

It teaches all sorts of skills taking something apart, working out how the parts work together and then re-assembling to a working condition without anyone getting hurt. I found it a good way to occupy children when they are bored. Clocks, switches, circuit breakers, motors, oscillating fans, toasters, simmerstats, thermostats - obviously defunct before they do - the list is long, .

Midwest · Oct 6, 2017

Only instructive thing I can remember doing as a child, was shorting out a spare car battery my Dad had, with a short piece of wire, and watch it glow & melt.

marconi · Oct 6, 2017

..and as a result you learned (and never forgot) about Ohmic heating, the phase states of copper and how they change with temperature, infra-red waves, energy conversion.....plus all the dangers of doing just that.

Engineering is a practical subject after all.

It's not to late to take something apart now for the shear joy of doing so. I wonder how many electricians have actually opened up an mcb, rcbo, rcd, hrc fuse, 13A fuse...if I ruled the world it would be done in college as part of their training

Midwest · Oct 6, 2017

marconi said:
..and as a result you learned (and never forgot) about Ohmic heating, the phase states of copper and how they change with temperature, infra-red waves, energy conversion.....plus all the dangers of doing just that.

Yeah of course I knew all that

HappyHippyDad · Oct 6, 2017

I opened up my faulty socket as Marconi suggested and I found a little man living in the neutral terminal. I asked him what he had been doing and he said he had planted some vegetables in the earth and had been watering them. Problem solved!

Had a couple of beers and in a silly mood

Midwest · Oct 7, 2017

That sounds perfectly believable

alasdairp · Oct 8, 2017

What was the make of the new faulty socket?
p.s. I loved what you found inside it!

telectrix · Oct 8, 2017

alasdairp said:
What was the make of the new faulty socket?
p.s. I loved what you found inside it!

膝部

HappyHippyDad · Oct 8, 2017

alasdairp said:
What was the make of the new faulty socket?
p.s. I loved what you found inside it!

Crabtree. It's the first time it's happened so I won't blame crabtree just yet!

happysteve · Oct 8, 2017

Here's a Crabtree double socket I had to replace FOC for a customer. Switches no longer able to be pressed into "on" position, and no power output on either half of socket. Been installed just over a year, had a reasonably high load: washing m/c plus tumble dryer, both running off one side of the double socket via a short 13A extension lead (as the double socket was too far away from the washine m/c and dryer). Terminations all good and tight, no sign of any thermal damage around terminals. Note the slight bulge near the left hand (as you look at the photo) earth terminal. Took it apart: plastic around switch springs had melted, meaning contacts no longer able to move.

Yeah, I'll be running my Crabtree stock down, I reckon.

static zap · Oct 8, 2017

Does that mean some computer designed them to , bake and fail
if abused at or just above 13A ?
(we all know - safety margins cost - Buy cheap buy twice)
Kitchen duty is ardous.

Wilko · Oct 8, 2017

static zap said:
Does that mean some computer designed them to , bake and fail
if abused at or just above 13A ?
(we all know - safety margins cost - Buy cheap buy twice)
Kitchen duty is ardous.

I wonder if the plastic used was rubbish? I'd give it a dip in a saucepan of 70C water and see if it goes chocolate teapot on us. Go on @happysteve - you know you want to

static zap · Oct 8, 2017

Wilko said:
I wonder if the plastic used was rubbish? I'd give it a dip in a saucepan of 70C water and see if it goes chocolate teapot on us. ........

I'm assuming a pass on that one ..only a little bulge present.

Midwest · Oct 9, 2017

happysteve said:
Here's a Crabtree double socket I had to replace FOC for a customer. Switches no longer able to be pressed into "on" position, and no power output on either half of socket. Been installed just over a year, had a reasonably high load: washing m/c plus tumble dryer, both running off one side of the double socket via a short 13A extension lead (as the double socket was too far away from the washine m/c and dryer). Terminations all good and tight, no sign of any thermal damage around terminals. Note the slight bulge near the left hand (as you look at the photo) earth terminal. Took it apart: plastic around switch springs had melted, meaning contacts no longer able to move.

Yeah, I'll be running my Crabtree stock down, I reckon.

View attachment 38725
View attachment 38726

If you can be arsed, I would contact Crabtree with your findings, see what they have to say. Did similar with a brand new BG switched FCU, which was isolating the neutral but not the live.

Wilko · Oct 9, 2017

After the eggs this morning I cooked up a plastic FCU, a conduit and cable offcut at 100C for 10 mins or so, till I got told to s@d off ... It all went down well with brown sauce. Ha ha ha. Conduit went floppy and cable sheath went limp as perhaps expected. But the FCU seemed unaffected. It's plastic was not softened as far as the pliers and screwdriver abuse test could determine. It was one with made in England written on it though.