When electrics go wrong!!!

[ipf]

Too easy, I'm out.

Well spotted. ?

 

[David Prosser]

Loose connection

 

[Rockingit]

Loose connection

View attachment 85950View attachment 85951

......where's the slot?

 

[SparkySy]

Is that 3 phases through 3 separate holes in the metal baseplate?

 

[David Prosser]

Is that 3 phases through 3 separate holes in the metal baseplate?

It's not a metal base.

 

[SparkySy]

Ah that's ok then! Must be my old eyes?

 

[brianmoooore]

Ah that's ok then! Must be my old eyes?

Not just yours, my eyes saw the same.

 

[Dartlec]

Just threw these out during a clear out - only time I ran into melting MCBs on a job, some years ago now.

From memory it was a loose terminal on the busbar so installation not manufacturer's fault, though did put me off the 'cheaper' brands for a good while...

 

[dodger421]

I’ve posted it before but this is what happens when you put 230V through a 110V coil. The coil voltage was applied whenever the machine control was on, so it would easily be sitting at the over voltage for 8 to 10 hours a day. I think it lasted three days before failing.

Physically the contactor looked fine, but you couldn’t manually push the contacts together like you should be able to.

Always always always check the coil voltage as well as the contactor rating, don’t just rummage around the parts cupboard for something that looks similar!

 

[RenatSha]

No idea, but the house was three phase and only 20amps/phase, 20amp MCB on a row of six others all covered by an RCD.

There was a poor connection in this outlet. The clamps in the outlet are loose. The contact has warmed up and the socket has melted!

 

[RenatSha]

There was a poor connection in this outlet. The clamps in the outlet are loose. The contact has warmed up and the socket has melted!

 

[RenatSha]

I agree! The circuit breaker requires maintenance every three months on schedule! The contacts must be tightened during servicing. Nobody did it.

 

[Simon47]

That's always worked for me. Mention smoke, and they're on site within the hour.

Only had to call out the DNO once when <whistles innocently> I managed to blow the main fuse. As there was no smoke, I was told "within 3 hours". But they refused to take my number - why would they, after all I'm on site; but they did insist on getting the householder's number (which they checked against their records) - so of course they contacted the householder who was at work.
DNO said "our engineer attended but there was nobody there" - we replied "oh no he didn't". They did manage to get him to go back, and then it was "he's standing outside the front door" - "oh no he isn't !"
Yup, he was at the wrong address. It's one of those places where the address can be confusing if you omit part of it - like "5 Greenfield, Whitegate, Anytown"; he was stood outside 5 Whitegate.

I have never had to play with an electric welder (other than a hour or two training as a student) so I would assume the high current secondary is not earthed to avoid a direct burn-out of the welder's earth. Or is it?

So was it two metal objects linked via conduit/CPC, and the welder's clamp was on one and the electrode arcing to the other?

There are a number of possibilities.
There's a brand of oil filled welders (Pickhill Bantam*) that I recall as being popular with farmers - I recall we had one at a farm I worked on as a lad, and a friend's farm has one - which have bare windings sat in a metal box full of oil. Apparently, if mishandled badly enough, the windings can distort and touch the case or each other. Thinking back, I can recall doing some welding and finding the gate I was working on had a bit of a tingle to it - at least we were wearing rubber wellies ! No RCDs back then.
Some might have the secondary connected to the supply earth as a safety feature if there isn't considered sufficient isolation. Then if someone decides that a big metal table should be earthed (either as a safety feature or just because it's bolted to some structural steelwork) then you've an alternative path separate to the welder earth.

* Dunno why it was called Bantam - it certainly wasn't Bantam in weight, they're 'kin heavy b'stards.

 

[nicebutdim]

Might still have one of those welders - must check...

 

[brianmoooore]

Might still have one of those welders - must check...

I have one and have used it in the last week. Was doing some repairs to my Ifor Williams trailer and the gas ran out on the MIG, so had to dig out the old faithful.

 

[Simon47]

As I recall they were great welders - could wind them up to 180A. I recall sticking an old carbon brush in the electrode holder and using the arc to cut stuff up.

 

[SparkySy]

They were a bullet proof welder! I learned to run beads on one that my dad still has when I was about 9 years old (ahem 1987?)! Them and the old Oxford units, still plenty about in operation today testament to how good they were/are!

 

[DPG]

Hello, I wanna say that one of the biggest causes of frequent circuit breaker tripping is the overloading of power boards. Most homes and apartments, even newer ones, don’t have enough power points to cater to, for example, a complete home entertainment unit setup. If circuit breakers in your home are tripping frequently, it could be down to circuit overload.

It does make sense that over-current protective devices can be tripped by excess current draw I suppose.

 

[Simon47]

But considering a typical setup is one or more ring finals, fed by a 32A MCB - so capable of a continuous (almost) 8kW. Even the most extravagant home entertainment system isn't going to get near 1kW.
I doubt that many homes suffer from frequent over-current trips.

 

[nicebutdim]

Member in question is in Islamabad, where it seems overloading is more common than in the UK.

 

[JosephandAmber]

Customers spotlights stopped working.

 

[ipf]

Member in question is in Islamabad, where it seems overloading is more common than in the UK.

It is, if you look at the buses.

 

[GBDamo]

I realise these pictures aren't as spectacular as the others but they do show how powerful 230V can be. Plus it's a very real outcome if safe isolation isn't adhered to.

If a L-N or L-E short at 230v can take even a little chunk out of steel alloy, hardened with vanadium, then I hate to think what it would do to a persons hand/arm holding a pair of non VDE pliers.

These are my (now spare) side cutters after I cut through a live cable some years ago (whilst my mind was busy elsewhere, thinking about a difficult relationship with a gorgeous yet crazy woman.). We must keep our minds on the job!

View attachment 84131 View attachment 84132

I have a pair of those wire strippers.

They started life as a £45 PAIR OF Klein side cutters and lasted about an hour and forty-five minutes.

I bought them off a trade counter while I was picking up a length of MT2 to stick an extra socket in an office.

The existing trunking ran just below the ceiling so it was an easy case of pulling a leg out of one socket, dropping it into the new and running a new leg back to the old socket.

What could possibly go wrong?

So pulled out my virgin side cutters out to cut out a notch for the new drop and.....bang.

Yep there was a 1.5 laying flat in the bottom of the trunking that I didn't see on account of not being attentive enough to get my lazy arse up and have a look.

In fairness to myself it was the flattest piece of cable I've ever seen, or not in this case, in trunking. It's like the spark ironed it.

Lessons were learnt and new procedures were put in place.

 

[ipf]

I realise these pictures aren't as spectacular as the others but they do show how powerful 230V can be. Plus it's a very real outcome if safe isolation isn't adhered to.

If a L-N or L-E short at 230v can take even a little chunk out of steel alloy, hardened with vanadium, then I hate to think what it would do to a persons hand/arm holding a pair of non VDE pliers.

These are my (now spare) side cutters after I cut through a live cable some years ago (whilst my mind was busy elsewhere, thinking about a difficult relationship with a gorgeous yet crazy woman.). We must keep our minds on the job!

View attachment 84131 View attachment 84132

Most sparks have or have had cutters to compare, I’d wager.
Regarding the short circuit cutting with uninsulated tools, it’s not the same short circuit current via your body (load). Nasty and dangerous, I know, but it’s not going to blow a hole in you. The arc from the metal tool is a real problem, also.

 

[willy fixit]

I realise these pictures aren't as spectacular as the others but they do show how powerful 230V can be. Plus it's a very real outcome if safe isolation isn't adhered to.

If a L-N or L-E short at 230v can take even a little chunk out of steel alloy, hardened with vanadium, then I hate to think what it would do to a persons hand/arm holding a pair of non VDE pliers.

These are my (now spare) side cutters after I cut through a live cable some years ago (whilst my mind was busy elsewhere, thinking about a difficult relationship with a gorgeous yet crazy woman.). We must keep our minds on the job!

View attachment 84131 View attachment 84132

I'll wager that all the sparks here have converted side cutters to wire strippers!
Since I did my second ones I've kept a new pair in the bag hoping I'll never have to take them off the card!

 

[James]

I'll wager that all the sparks here have converted side cutters to wire strippers!
Since I did my second ones I've kept a new pair in the bag hoping I'll never have to take them off the card!

Most will not admit to it.

personally, of course I have never done it.
especially not whilst up a ladder and subsequently scaring the brown stuff out of my rear end.
Pity that I have NEVER had that learning experience.

now where did I leave my pet unicorn?

 

[Mike Johnson]

I have converted a pair of wire strippers to side cutters, well put it this way the strippers where no good for stripping cable after my brush with 230volt, luckily only one of the Phase's.

 

[SparkySy]

I have never done it, I especially didn't do it when I was working on a 50a sub main in a gunsmiths, through a 10mm twin and earth with croppers, and it didn't blow the stripping notch clean off them and splatter molten copper all over! No not at all, and I didn't scare myself and half the people who were in there who thought it was a live round going off and all ducked in sync!

 

[Raptor0014]

Got a phone call earlier this week. Here is a brief synopsis to explain the pics

Customer - "Hi, occasionally when I use my tumble drier there is a strange smell from near the plug and it sometimes trips the electric"

Me - "Sounds like a faulty drier, if you unplug the drier does anything else cause the electrics to trip?"

Customer - "No, just the drier and it is getting more frequent"

Me - "Ok, unplug the drier and don't use it. I will be with you on Friday morning (4 days from the call)

Turns up on Friday morning to find they had still been using the drier and it had decided to let go. The madness continued when I found they were still using the extension lead it blew in! Not anymore after I cut the plugs off both.

 

[brianmoooore]

unplug the drier and don't use it. I will be with you on Friday morning (4 days from the call)

Turns up on Friday morning to find they had still been using the drier

Had a similar one to this, but with a washing machine. Before the few days were up, they had tried to repair it themselves, and the lady of the house had electrocuted herself.
Made more tragic by the fact that the socket would have been RCD protected within a few weeks, and there was a launderette five doors away in the street.

 

[Mike Johnson]

@Raptor0014 Surge protected, but not Muppet protected, the fish smell is quite distinctive with out the visual aids.

 

[Mike Johnson]

You guys have seen this before, but thought it was worth posting again, the smell in the room was a very distinctive fish smell, it comes from running two 3Kw fires off the same double socket, neither the MCB or RCD reacted to the overload, just got very smelly in the room.

 

[Raptor0014]

You guys have seen this before, but thought it was worth posting again, the smell in the room was a very distinctive fish smell, it comes from running two 3Kw fires off the same double socket, neither the MCB or RCD reacted to the overload, just got very smelly in the room.


View attachment 93240

That’s quite concerning that neither protective measure reacted to that.

Then again if nothing created a short then it’s a failure of the socket. Especially if it was connected to a 32a MCB as 26a it would be happy with. Guessing the materials in the socket weren’t rated to withstand 26a for that long.

 

[UKMeterman]

You guys have seen this before, but thought it was worth posting again, the smell in the room was a very distinctive fish smell, it comes from running two 3Kw fires off the same double socket, neither the MCB or RCD reacted to the overload, just got very smelly in the room.


View attachment 93240

Is that one of the ones with lever contacts, rather than screws?

 

[Mike Johnson]

Is that one of the ones with lever contacts, rather than screws?

Yes, it's French Legrand socket off a 20amp MCB.

 

[UKMeterman]

Me thinks I want to stick to crabtree...

 

[Mike Johnson]

The socket was Legrand, but the MCB and feeding RCD where both Hager and both tested out as per the specifications for them, I can only think that the fan and thermostat's for the heaters did not come on at the same time consistently, so an intermittent accumulative overload over a long period.

 

[pc1966]

The socket was Legrand, but the MCB and feeding RCD where both Hager and both tested out as per the specifications for them, I can only think that the fan and thermostat's for the heaters did not come on at the same time consistently, so an intermittent accumulative overload over a long period.

The back plate looks a bit corroded, maybe contacts were a bit tarnished as well?

In any case a 30% overload (26A on 20A rating) is not likely to trip a MCB but would definitely be considered unacceptable design practice. I guess the approval of double sockets was kind of based on the assumption you would not have two max loads on the same one...

 

[Mike Johnson]

The corrosion is quite normal on the ground floor of an old French farm house, no DPC or DPM so walls are always damp, if does not seem to bother the French,

Believe it or not they where not on each socket, but supplied off an extension lead onto lefthand outlet, oh can I say receptacle.

 

[pc1966]

Believe it or not they where not on each socket, but supplied off an extension lead onto lefthand outlet, oh can I say receptacle.

Well they can't really complain about the socket in that case being poorly made as it was clearly overloaded by 160%.

Now if only the French had a 13A fuse in the plug...

 

[Raptor0014]

Got a call out yesterday afternoon. Told electrics had tripped, turned back on and keeps tripping every few minutes so could I come and check as had no power to sockets, kitchen and half the house.

Arrived to find the following:

Basically the far right breaker was a 50A supply to a second DB for one half of the house (big old farmhouse) which includes a 10.5kw shower, sockets, immersion and lights. Also 2 x 32a socket circuits (one of which was the kitchen) a 20a socket circuit and 16a second immersion.

All hanging off a 63a RCD and the board had never been checked in the 18yrs since it was installed.

So I managed to give them some power back. But told them they need a new board now asap and a full EICR doing, as I wouldn’t change a board without doing it anyway (especially not on house where I’ve been called to a melted board) and investigation was needed to check why that 50A breaker had obviously also overheating given the melted plastic around the busbar connection.

 

[timhoward]

Received from customer:

Going to see it later today, apparently the fitting says "Made in West Germany" on it, so first question is how many others they have.
Second question is what that taped up wire is doing.

 

[pc1966]

apparently the fitting says "Made in West Germany" on it

Well that kind of dates it! When did they reunify, some time around 1990?

 

[timhoward]

Well that kind of dates it! When did they reunify, some time around 1990?

Yeah - the wall fell in Nov 1989. It's at least had a re-wire since.

 

[Bob Fleming]

Received from customer:

View attachment 94306

Going to see it later today, apparently the fitting says "Made in West Germany" on it, so first question is how many others they have.
Second question is what that taped up wire is doing.

Taped wire will be the permanent live for if this was to be an emergency light. Currently (hopefully!) choc-blocked and then taped.

 

[littlespark]

The Berlin Wall fell in ‘89 I think… all thanks to knight Rider himself, David Hasselhoff.

 

[pc1966]

The Berlin Wall fell in ‘89 I think… all thanks to knight Rider himself, David Hasselhoff.

One of my regrets was not going to the Pink Floyd concert in Berlin to mark that.

There was a minibus going from Dundee arranged by Groucho's (closed now, was 2nd hand record shop and outlet for local gig tickets) but various friend could'nd be bothered and I gave up on the idea.

 

[DPG]

One of my regrets was not going to the Pink Floyd concert in Berlin to mark that.

There was a minibus going from Dundee arranged by Groucho's (closed now, was 2nd hand record shop and outlet for local gig tickets) but various friend could'nd be bothered and I gave up on the idea.

You'd need to go for a week just to listen to one Pink Floyd song though!!

 

[littlespark]

I remember groucho’s!

The nightlife was varied when I lived up there.
No1’s, Deacon Brodies, O’Neills… student union, of course.
Mardi gras, fat sams, de’stihls….

That all stopped when we moved to the posh end of Carnoustie

 

[sarky spark]

Opening an external lighting joint box.