Could have had a fire.

[Russdl]

The old dishwasher has given up the ghost. No power. RCB are all on so I checked the fuse and was mildly shocked to see how hot it had obviously got prior to failing. I didn’t think this sort of thing could happen. Any ideas what went wrong?
 

It’s the original plug and fuse as fitted to the dishwasher at point of sale. 

 

[ProDave]

At least it's a simple repair, new plug and new fuse.

[dpmiller]

Moulded plug syndrome...

 

seriously tho? the heater takes a fair bit of juice and there's a degree of heating and oxidising at the contacts of the fuse due to this current. This is a vicious circle- heating reduces the springiness of the contacts in the plug, makes more heat, causes higher resistance, which makes even more heat...

 

it's why it's worth taking a look inside any plug that is on something over a kW, every now and then.

[Russdl]

@ProDave yep, simple repair. I was concerned that there was something more significant going on here but if as @dpmiller says this is not unusual then I’ll change it. 
 

Makes me nervous though, that got hot and I’ve not seen that in a long time, guess I ought to do as advised and take a peek inside plugs every now and again!

[ProDave]

A fuse, by it's nature is a resistor, and will get hot at close to it's full normal load.

 

Fused connections units of some makes are notorious for failing like this, often with a fishy smell.

[TonyT]

42 minutes ago, Russdl said:

The old dishwasher has given up the ghost. No power. RCB are all on so I checked the fuse and was mildly shocked to see how hot it had obviously got prior to failing. I didn’t think this sort of thing could happen. Any ideas what went wrong?
 

It’s the original plug and fuse as fitted to the dishwasher at point of sale. 

 

Could you post a picture of the plug from a different angle to see the pins please.

 

from the angle don’t see the insulated section?

[Russdl]

@TonyT sure can:

 

 

 

[TonyT]

All good, was just the angle in the first picture, as Dave says hopefully a new plug and fuse will sort it out

[ProDave]

I would replace that socket, see the crack from the L pin.

[Russdl]

11 minutes ago, ProDave said:

 

I would replace that socket, see the crack from the L pin.

 

I saw that in the photo as well (couldn’t see it before) I’ll replace it. 
 

Is that likely to have had any bearing on my hot plug or is it just coincidence?

[Roys]

Coincidence I think

[dpmiller]

related to the heat. there's a brownish tinge to the Live entry on the socket.

[Roys]

2 hours ago, dpmiller said:

.

 

Edited March 28, 2021 by Roys

[Roys]

In summary, the plug is knackered, cut it off and change it.

The socket has signs of heat damage from the plug, and is cracked, the overheating may have been a factor in it cracking it could also been a slightly misaligned pinned plug being persuaded into the socket. Doesn’t really matter the socket needs changed as well.

 

When you change the plug and socket don’t fit cheapoes. I always used to fit MK, hundreds of them, but the quality is not what they used to be. I tend to fit Hager or Click now, probably only very slightly more expensive than cheapoes but they are better.