Shower connection burnt

[Mustang]

Hello all

I have had this electric shower installed for about 3 years and has been fine until today when the missus smelt burning from it. I took the cover off and the neutral connection on the connector block has melted.(As you can see in the picture) The shower is 7200W and is fed by a 6mm cable which I believe to be sufficient, so shouldn't really overheat. The connection was secure so can rule out arching. Just wondered if anyone could tell me why this has happened when it has been ok for 3 years and amount of usage hasn't changed?

Many Thanks!!

 

[dufjax]

Well apart from the fact that the tails from the shower look like 10mm

Only thing I can suggest is a loose connection on neutral. You did mention the connections were fine but the connector blocks used in these devices are the best of quality and it's often quite easy to brake them by over tightening.


Anyone else got any thoughts?


Jim

 

[Bobby B]

nearly almost a loose termination seen hundreds like it, may have been tightened onto the insulation also but if you can rule this out which you can't really now its burnt i aint got a scooby

 

[Notsosmart]

It does look as though the neutral has been arcing ~ with the connector destroyed how do you know it was tight? Highly unlikely but maybe check other end for tightness etc.
Undertake some tests; IR, continuity etc.

 

[Mustang]

Thanks for all the quick replies. Loose connection it is then. I think I will re-make the connection then do an IR test and continuity test to make sure all is ok. Thanks alot everyone!!

 

[Notsosmart]

Remember Do NOT do an IR test whilst connected to the shower unit.

 

[bugsy]

absolutley defo loose connection generating a bit of heat. ,replace connector and you will proberblt have to cut back cable

 

[Phil]

my moneys on a loose connection

 

[robsparky1975]

Looking at he picture loose connection/crimped insulation on terminals,noticed how the outgoing section of cable to shower element looks fine so would point to incorrect termination on install neutral,sometimes when overtightened the terminal screw actually spins and slackens off slightly i have found this on sockets as well,manufacturers give guides of nm of torque for screw terminals but that is a bit tough to gauge with your hand,its the heat/time thing with showers and any large load eqpt,give it time(3 years about right) give it heat(loose connection) and on that load not surprising,i would hope that these shower companies could make a better termination for cables as this is quite common place for faults on them,perhaps something like a push in connector.

 

[steamboatwilly]

Neutral terminals sometimes tend to loosen (earth current effect I'm told).....common on immersions but less so on showers. Looks like a loose connection on install then.

 

[rocker]

Try covering it in foil and putting it on gas mark 4 for two hours, basting regularly.

 

[Notsosmart]

 

[steamboatwilly]

Yes, quite....should be Gas Mark 4 for 1.5 hours!

 

[rocker]

Ooh someone's got a posh fan-assisted oven!

For us plebs it's 2 hours.......

 

[Des 56]

. I think I will re-make the connection then do an IR test and continuity test to make sure all is ok.

I would advise changing the connector block as well

 

[Hawk81]

After looking at the picture i would agree with most replies and say that the burn out has been caused due to a bad connection on the neutral. I would disagree with the first reply and say that it does look like a 6mm t&e suppling the shower not a 10mm. 10mm t&e usually tends to not to have a single stranded earth wire as the cable in the picture clearly does.

 

[dufjax]

After looking at the picture i would agree with most replies and say that the burn out has been caused due to a bad connection on the neutral. I would disagree with the first reply and say that it does look like a 6mm t&e suppling the shower not a 10mm. 10mm t&e usually tends to not to have a single stranded earth wire as the cable in the picture clearly does.

Your probably right, lol

Jim