Re: How hot should an LCD TV transformer get?

Yes some are definitely dodgy. I wonder if they are made for a mains voltage
with a lower top limit than ours for some reason.
I've never understood why they allow them to get so hot. After all, all that
heat is power you are paying to use!

Brian

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Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email: briang1@xxxxxxxxxxxxxxxx
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"Woody" <harrogate3@xxxxxxxxxxxxxxxxx> wrote in message
news:suzjk.34260$3L5.7074@xxxxxxxxxxxxxxxx
"Adam Lipscombe" <adam.lipscombe@xxxxxxxxxx> wrote in message
news:1217309151.9356.1@xxxxxxxxxxxxxxxxxxxxxxxxx

Apologies if this is not strictly a digital question. I cannot think of
better forum to ask.

I recently bought a cheap and cheerful LCD TV for our camper van. It can
run off 12 volt DC or 240 AC, with a supplied transformer. The
transformer looks like the type you get with a laptop - a separate oblong
black box.

When working from the mains the transformer gets hot - very hot. Last
night we watched 2 hours of telly and when time came to put it all away I
could hardly pick the transformer up. It was almost too hot to hold.

I am worried about a potential fire risk.
Is this normal? How hot do they normally get?


Thanks - Adam



Modern PSUs often run warm, sometimes a little too warm, but it should not
run too hot to touch. This suggests either cost cutting on behalf of the
manufacturer or that someone has replaced the PSU with an unsuitable
substitute.

Look at the TV power rating - divide power by volts to get current
requirement, then look at the rating of the PSU. I would personally not
expect the TV to draw more than about 70% or so - tops say 80% of the PSU
rating. If it is higher than that there is no wonder it is getting hot.

If it appears to be the wrong or an underrated PSU then take it back to
the supplier under the 'unfit for purpose' legislation - remember your
contract is with the supplier not the manufacturer so don't be fobbed off.
On the other hand a call to the manufacturer/importer to see if they have
encountered this problem before may not go amiss.

If all seems OK ratings-wise and you get nowhere with the supply chain
then you may have no option but to replace it at your own cost. Places
such as www.maplin.co.uk will supply you with a switched mode unit that
even as a plug-top may be rated way above that which you already have and
will be considerably lighter to boot.


--
Woody

harrogate three at ntlworld dot com



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