Induction hob failing with a loud bang.

[Qedelec]

Hi thought I’d share a recent project with you lovely people.
A while back, a Tefal induction hob (single plate), we bought failed with a loud bang. My first reaction was it didn’t cost a huge amount so bin it. Then my recycle side stepped in and I decided to investigate my it had failed.
If you have heard of similar hob failures you are not alone, they seem to be quite common.
The first component I found to have failed was a 12.5A fuse enclosed in heat shrink that had shattered. I presume due generated back EMF.
The next was a bridge rectifier gone short circuit. Replacements obtained I refitted and applied power.
All the lights came on when I pressed on, job done I thought so pressed power button…..BANG.
I then found I had failed to look further and the IGBT (insulated gate bipolar transistor) was also short circuit so more components ordered.
Having repeated the first replacements and the IGBT, I reapplied the power, and this time when I pressed power it worked.
I don’t encourage anyone to follow me, as I have a background in electronics, so know what to expect when examining a circuit. But this seems to be a common failure in these plug in hobs.
Incidentally the IGBT I ordered was not supplied, but a higher rated one was, so I suspect this has been a problem for a while.
I hope this will help someone. Just because it’s broke, doesn’t mean it should end up in landfill.

 

[bobmeade]

Interesting - it does seem the components are not too easy to obtain, mainly China for the IGBT - I've a couple of these I'm awaiting parts for.
It does seem the root cause, is the IGBT shorting out, taking with it any other components before it.
I wonder if the real root cause, is overheating of the electronics? Due perhaps in the Kitchen environment, there will be plenty of heat coming from ovens etc. I know Induction hobs all use a cooling fan, but if it is pulling in hot air - the cooling, will be reduced.

 

[fourtytwo]

IMOP combination of poor design and fake parts. Beware where you buy your replacements from, not the like of Ali-Express or some of the more dubious Fleabay suppliers I hope