I was wondering if anyone knows where I can get hold of a 24V 850mA
power supply adaptor - it's for a set of decorative lights as my
original adaptor has broken.

I don't know the faintest thing about electronics, so I don't know
where to look for one. I'm in the UK.

If anyone could help, I'd be most grateful. Thank you.

In article . com>,
> wrote:
> I was wondering if anyone knows where I can get hold of a 24V 850mA
> power supply adaptor - it's for a set of decorative lights as my
> original adaptor has broken.

Easiest option is probably somewhere like Maplin.

--
*If a thing is worth doing, wouldn't it have been done already?

Dave Plowman London SW
To e-mail, change noise into sound.

I've just taken a look but there's nothing suitable - they're all 12V
or AC/DC, whereas I need 24v AC/AC.

Thanks all the same.

> wrote in message
ups.com...
> I've just taken a look but there's nothing suitable - they're all 12V
> or AC/DC, whereas I need 24v AC/AC.
>
> Thanks all the same.
>
>
They probably don't exist as a universal wall adaptor at that voltage, at
least I've never seen one. If you have any paperwork for the lights you
could look for an address or phone number and try the manufacturer. Failing
that, have a look at your local car boot sale, people often dump old AC
adaptors into a box of junk and sell them off for a few pence, you might get
lucky.

You need to get one of the same voltage and the same or higher current. I
have a 24v one I use to power a home built battery charger, and IIRC it's
off an old document scanner.

As a last resort, if the lights are really valuable to you, you might find a
local hobbyist who is prepared to knock together a power supply, but it
likely won't be the cheapest option.

There's not many parts needed for an AC-AC power supply. A 240V-24V
transformer from Maplin or RS etc, a case to mount it in, mains cable, LV
cable and a few sundry items. It's technically straightforward enough, even
for a beginner, but I would never recommend a mains powered project for a
total newbie, it's too dangerous.

Dave

Dave

wrote:
> I've just taken a look but there's nothing suitable - they're all 12V
> or AC/DC, whereas I need 24v AC/AC.
>
> Thanks all the same.
>



So long as you're just running incandescent lights you can use AC/DC, it
won't make a difference.

What's wrong with the original unit? Sometimes a momentary short will
blow an internal fuse that can be replaced.

"James Sweet" > wrote in message
news:cMS6f.4919$tl5.5@trnddc02...
> wrote:
>> I've just taken a look but there's nothing suitable - they're all 12V
>> or AC/DC, whereas I need 24v AC/AC.
>>
>> Thanks all the same.
>>
>
>
>
> So long as you're just running incandescent lights you can use AC/DC, it
> won't make a difference.
>

That depends . I have a set of novelty lights which have a control box, and
the lights are switched using small triacs. If I was to power them off DC
the triacs would latch on all the time.

Dave

In article om>,
> wrote:
> I've just taken a look but there's nothing suitable - they're all 12V
> or AC/DC, whereas I need 24v AC/AC.

Nothing lost if it's broken by opening up the wall wart and seeing if it's
just a transformer inside. If so, Maplin etc might have one that fits.

--
*Why don't you ever see the headline "Psychic Wins Lottery"?

Dave Plowman London SW
To e-mail, change noise into sound.

>
>
> That depends . I have a set of novelty lights which have a control box, and
> the lights are switched using small triacs. If I was to power them off DC
> the triacs would latch on all the time.
>
> Dave
>
>
>


True, I was thinking these were just simply lights.

That said, I've modified 12VDC wall warts to put out AC for a couple of
novelty lamps that had 12v syncronous motors in them. The wall warts
were the rare type held together with screws so it was a simple matter
to remove the rectifier/filter board and replace it with a fuse.

> wrote in message
ups.com...
> I've just taken a look but there's nothing suitable - they're all 12V
> or AC/DC, whereas I need 24v AC/AC.
>
> Thanks all the same.
>

What about using two 12VAC Wallwarts and wiring the two outputs in series.
Measure the outputs, if you get 0 volts then just swap the output wires of
one as the AC is out of phase and cancelling each other out.

Wes.

wrote:

> I was wondering if anyone knows where I can get hold of a 24V 850mA
> power supply adaptor - it's for a set of decorative lights as my
> original adaptor has broken.
>
> I don't know the faintest thing about electronics, so I don't know
> where to look for one. I'm in the UK.
>
> If anyone could help, I'd be most grateful. Thank you.
>
At least on this side of the pond (i.e. US), 24V is very common for
furnace controls, so transformers producing that voltage are available
at most hardware stores.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

> At least on this side of the pond (i.e. US), 24V is very common for
> furnace controls, so transformers producing that voltage are available
> at most hardware stores.
>


Furnaces I've seen all have internal transformers, but 24v wall warts
are indeed very common for security systems, and I've seen a few
doorbells that used them instead of permanently wired in units. IIRC UK
doorbells don't use 24v though.

wrote:
> I was wondering if anyone knows where I can get hold of a 24V 850mA
> power supply adaptor - it's for a set of decorative lights as my
> original adaptor has broken.
>
> I don't know the faintest thing about electronics, so I don't know
> where to look for one. I'm in the UK.
>
> If anyone could help, I'd be most grateful. Thank you.
>
CPC Preston.. Website.. Google for CPC

Ron(UK)

--
Lune Valley Audio
Public address system
Hire, Sales, Repairs
www.lunevalleyaudio.com

Thanks for the responses everyone.

I've looked around the CPC website, but am completely lost. I've put
'24V AC' in the search box but there are 82 results. If it doesn't say
'DC', is it automatically AC-AC? How do I know what wattage I need -
it doesn't say on my original adaptor.

All I know is I need a 24V AC-AC 850mA power supply/mains adaptor, but
as I don't know anything about elctronics, the whole list on the CPC
site just bamboozles me.

Cheers.

> wrote in message
ups.com...
> Thanks for the responses everyone.
>
> I've looked around the CPC website, but am completely lost. I've put
> '24V AC' in the search box but there are 82 results. If it doesn't say
> 'DC', is it automatically AC-AC? How do I know what wattage I need -
> it doesn't say on my original adaptor.
>

That's easy. Multiply the voltage by the current to get the wattage. 24 x
0.85 = 20.4 Watts.

However, you don't want to run it flat out, a 25 Watt or 30 Watt adaptor
would be good.

> All I know is I need a 24V AC-AC 850mA power supply/mains adaptor, but
> as I don't know anything about elctronics, the whole list on the CPC
> site just bamboozles me.
>

I think you're flogging a dead horse to be honest. 25 Watt, 24V AC wall
adaptors aren't exactly a common generic item I'm afraid. You may find one
eventually, at a price, but I can't think of any reason a manufacturer would
make a 'universal' 24 V AC adaptor, no demand you see. Most equipment
designed to run off aftermarket adapters requires DC at 12V or below.

Your best bet, if you don't have the manufacturer's details for your lights,
might be to find a piece of equipment which uses a similar adapter, ie a
similar light set, and ordering a replacement from the manufacturer.

Can you tell us something about the lights? ie are they electronically
sequenced from a control box? Are they Christmas style lights or something
else?

Dave

They're like Christmas tree lights - i.e. in a sequence, but they don't
flash or anything, they're just either on or off (if that makes sense).

wrote:
> Thanks for the responses everyone.
>
> I've looked around the CPC website, but am completely lost. I've put
> '24V AC' in the search box but there are 82 results. If it doesn't say
> 'DC', is it automatically AC-AC? How do I know what wattage I need -
> it doesn't say on my original adaptor.
>
> All I know is I need a 24V AC-AC 850mA power supply/mains adaptor, but
> as I don't know anything about elctronics, the whole list on the CPC
> site just bamboozles me.
>
> Cheers.
>

I just had a look and I only see AC output transformers up to 500mA, if
your device draws more than that then you'll need a bigger capacity adapter.

wrote:
> They're like Christmas tree lights - i.e. in a sequence, but they don't
> flash or anything, they're just either on or off (if that makes sense).
>


Odd that they use a transformer, all our miniature Christmas lights are
in series directly off the mains. Anyway it sounds like a DC output
power supply would work just fine, if you'd like to find out before you
buy one, connect the light string to the battery in your car, if it
lights up dimly then they work fine on DC.

"James Sweet" > wrote in message
news:OBs7f.4889$Yn4.1050@trnddc03...
> wrote:
>> They're like Christmas tree lights - i.e. in a sequence, but they don't
>> flash or anything, they're just either on or off (if that makes sense).
>>
>
>
> Odd that they use a transformer, all our miniature Christmas lights are in
> series directly off the mains.

*Very* common here in Europe, James. The EU has very strict regulations on
electrical safety, and a very sizable amount of low power 'novelty' lighting
is LV nowadays.

Dave