Re: Microwave

I have got a nn a773 combi oven which blows the fuse when starting the
microwave cooking cycle. It blows the fuse in a raction of a second but
I dont find any signs on the inverter board at all. The fuse only blows
when the inverter board is powered (with the magnetron disconnected) It
almost looks like a safety switch makes the fuse blow. (I think it cut
out due to the magnetron fan not running)The fuse on this model will
also blow if the door switches are misaligned.
Why does no one wants me to touch the inverter board, it has straight
forward components on it?
Harry Collingwood wrote:
> On Wed, 31 Aug 2005 21:11:43 +0100, "Graham" <me@xxxxxxxxxxx> wrote:
>
> >
> >> Does anybody have some info or know where I can get a schematic on a
> >> panasonic microwave model nn-s543bfw?
> >> It runs for a 23 seconds or so then shuts off?
> >> Thanks in advance
> >
> >
> >I don't recognise that model (I am in the UK)
> >Is it an "inverter" HV PSU?
> >
> >If so, have a close look at the magnetron magnets.
> >I bet one or both of them are cracked from overheating.
> >
> >If you just replace the Mag, it will work for a while, but it will probably
> >fail again due to being over-run.
> >
> >So it's a replacement Magnetron and a replacement inverter, Panasonic don't
> >encourage you to repair this item, bur if anyone has, I would be interested
> >to hear.
> >
> >I recommend people stay away from these models, and go for a conventional HV
> >transformer type.
> >
> >--
> >Graham.
> >
> >
> >
> >%Profound_observation%
> >
> Yeah,I got stitched up with this model [AN772] HV blew a transistor in
> the inverter board and PAN wanted 160 pounds to repair it! Seems that
> the whole inverter board needs a replacement[if you exchange your
> board]
> All this for one transistor s/c.As a qualified[if retired]Microwave
> engineer Pan finally agreed to supply an exchange board for 90 pounds
> plus VAT.
> I refused as it is likely to fail again,and bought a Sharp Combi for
> 120 pounds,does the same job with conventional HV .
> I have since found out that PAN have had trouble with this HV system
> and they were warned this would happen. They thought it would be more
> appealing if the microwave was lighter.
> Sharp,Sanyo etc would not use this method of HV supply.
> PAN. took no notice and left the repair bill to we customers,I'll
> never buy Panasonic again .

.

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