The wall wart transformer for a 5 metre multi coloured LED
light string has stopped working. Can I use a transformer
like the ones connected to my 12v downlighters.

I assume I just need to sort out the polarity?

John

--
John Mulrooney
NOTE Email address IS correct but might not be checked for a while.

Being with you forever just wouldn't be long enough

On 27/08/2014 10:48, JTM wrote:
The wall wart transformer for a 5 metre multi coloured LED
light string has stopped working. Can I use a transformer
like the ones connected to my 12v downlighters.

I assume I just need to sort out the polarity?


You need a wallwart with an output that matches the voltage of the old
one (Which may be AC or DC) and has a current rating at least as large
as the one you're replacing. Polarity only matters for DC.

If your downlighters are halogen, the odds are that the transformer is
just that, supplying AC, and if you use it to try and power anything
requiring DC, it will probably destroy the latter.


--
Tciao for Now!

John.

Yes you need a bridge rectifier, and then the peak voltage may well be
greater then expected, whether this is going to be true under load is
difficult to say.
Brian

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From the Sofa of Brian Gaff Reply address is active
"John Williamson" wrote in message
...
On 27/08/2014 10:48, JTM wrote:
The wall wart transformer for a 5 metre multi coloured LED
light string has stopped working. Can I use a transformer
like the ones connected to my 12v downlighters.

I assume I just need to sort out the polarity?


You need a wallwart with an output that matches the voltage of the old one
(Which may be AC or DC) and has a current rating at least as large as the
one you're replacing. Polarity only matters for DC.

If your downlighters are halogen, the odds are that the transformer is
just that, supplying AC, and if you use it to try and power anything
requiring DC, it will probably destroy the latter.


--
Tciao for Now!

John.

On Wednesday, 27 August 2014 10:48:54 UTC+1, JTM wrote:
The wall wart transformer for a 5 metre multi coloured LED

light string has stopped working. Can I use a transformer

like the ones connected to my 12v downlighters.



I assume I just need to sort out the polarity?

Some of the colour changing LED strips work at 5V anything more will destroy them, so you really need to know what voltage your particauly strip needs.
The original adapter should say oin it what V and I or power you need.