Cable burnt out

[catdog]

So was visiting a friend and they happened to have a problem with their cooker....it stopped working mid cooking a dinner!

Ok so BEKO electric oven with Gas hob.

Rating of electric oven is 2.5KW

Was hard wired into a FCU with a 13Amp fuse.

Wired in what I assumed to be 1.5mm2 white flex. (could have been less)- As far as I know the cable came wired in from manufacturer and initially had a plug top on it as a lot of ovens do these days.

So I was thinking the 1.5 would have been acceptable however it clearly had burnt out inside the cooker back plate and the fuse had blown,

Installed a bigger cable and put a clamp meter on it, was drawing about 11 amps.

Any body seen this sorta thing before? especially when it came pre-wired?

thanks.

 

[Lucien Nunes]

I assumed to be 1.5mm2 white flex. (could have been less)

Don't assume, read it off the side of the cable or measure it!

the 1.5 would have been acceptable

For 2.5kW, yes.

Installed a bigger cable

Why?

Any body seen this sorta thing before

Of course. A spark will see hundreds of burnt out connections.

The problem was either incorrect cable insertion, faulty terminal or inadequate tightening torque. If you properly cleaned all the corrosion off the terminal clamp and it is intact and correctly tightened it shouldn't happen again. Did you test the resistance of the finished connection, and the insulation of the terminal where the plastic might have carbonised with the heat?

 

[telectrix]

probably a poor connection on the L terminal.

 

[GMES]

As telextric says probably a loose connection on live, and it could have come from manufacturers like that, it usually will say on instructions to make sure factory connetions are tight, seen it loads of times.

 

[catdog]

thanks Lucien.

When I say assumed was because could only guess- tried to read a size on the cable. Wanted to replace the cable anyway due to this type of fault couldnt say that other parts of the cable hadnt been damaged.

Was also asking if people had seen bad connections on factory fitted cables rather than generic bad connections- cause I know they more common than mud! I did clean the terminal and the carbon off before re-terminating.

 

[catdog]

thanks guys.

Yeah i doubt the guy who installed it ever checked the connections. Apparently the 'spark' who installed it had initially connected the flex to the old ccu protected by a 32A mcb.....but that was changed few months ago. the cooker had been in almost 3 years but just shows what can happen when things aren't installed correctly.

 

[Darkwood]

This most likely would not have had the flex been crimped as BS 7671 requires unless the terminals are suitable for fine stranded cables.. as i can see its a screw terminal they will not be thus you need to crimp these cores before remaking off.

Its easy to lay blame on loose connections but if the fine wire is not crimped the connection may seem solid where as a good proportion of the strands haven't been clamped so in this case unlikely that it was loose just that it was incorrectly terminated. If they want to they can get your call out fee back if you write this on the invoice that the previous installer had fitted it incorectly.

 

[Lucien Nunes]

Sure probably as many or more on factory-wired stuff than anything else. I don't know what's more annoying, a connection that wasn't done right and wouldn't have burnt out it if had been, or one that is pushed so near its maximum that it will inevitably burn out if the resistance goes up even a little bit. The worst is when a 2p crimp that makes poor contact destroys an expensive module. White goods are regular offenders.

 

[Darkwood]

Im very surprised it came prewired using a external mounted connection unit like that i suspect it may have been a showroom model that had been flexed to show the clock and controls lit up, factory terminated products don't usually use this method as its prone to loosening in transit and been cheap and tacky snagging the flex would damage the terminal box so it wouldn't be in their interest to do it this way.

Just an observation not saying you are telling fibs .... if it is the case its factory wired like this then they deserve all the headache they receive and i would send a email to them if the flex is indeed uncrimped to recoup the customers callout fee.

 

[catdog]

Im very surprised it came prewired using a external mounted connection unit like that i suspect it may have been a showroom model that had been flexed to show the clock and controls lit up, factory terminated products don't usually use this method as its prone to loosening in transit and been cheap and tacky snagging the flex would damage the terminal box so it wouldn't be in their interest to do it this way.

Just an observation not saying you are telling fibs .... if it is the case its factory wired like this then they deserve all the headache they receive and i would send a email to them if the flex is indeed uncrimped to recoup the customers callout fee.

Me? A fibber?? Shocked haha

As didnt install it can online go on what was told. Yes my thoughts were that it did appear a cheap connection. But then I always think alot of electric oven connections seem cheap and flimsy....and really awkward to ipen sometimes ha!

 

[Rockingit]

Those connection boxes are commonplace these days - I replaced one for a customer a couple of weeks ago that had completely destroyed itself due to poor termination by the installer (probably DIY). Also, cookers on flex are on the up, too. The drive for energy efficiency and getting the arrow up as high as possible on that showroom A > G sticker (or whatever it is) has had the bi-product of lowering the consumption so long gone are the days of ugly cooker cable.

 

[Eddiesparks]

Get an impact driver and rattle the **** out of it haha

 

[overskilled]

Its a beko...no chance of them coughing up....they don't even return phonecalls
I have a beko washing machine...in 2 years of LIGHT use it has chewed up 1 motor, 2 pumps....cheap junk