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<font color='#0000FF'>OK, I have noticed that quite a lot of you are technically minded.

My question is this, last year I bought one of those cool boxes you plug in to your car ciggy lighter socket, the problem is by the time I have arrived at my destination it hasn't actually cooled down enough to keep thing cold.  

What I would really like to get hold of is, if there is such a thing as an adapter you plug in to the mains.  So if I am staying somewhere overnight I can take it in to a B & B and keep it running.

So what I have been for an adapter which connects the lighter plug to another lead which goes in the mains, I presume some sort of transform would be needed but don't seem to be able to find one, tried looking at marine / caravan type places.

Does anyone know if such a thing exists or is even possible.

Cheers

Fiona
 

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Hi Fiona. that's very easy. Your car's battery provides 12v dc current whereas the mains in your home is typically 220V ac current. You need a simple/cheap transformer which you can buy in may different places including Maplins on the internet, or call them and explain and you'll get exactly what you need. Shouldn't cost more than a tenner.

HTH - regards
Philip
 

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<font color='#810541'>I got a 'power pack' sort of thing that is supposed to be charged up itself, and it can then provide 12v power for things like this and also has some jump leads to get a car started.  I used it to run a fridge thing when camping a couple of years ago, but it only lasted about an hour on a full charge.

I've tried it plugged into the mains to power the fridge and it worked, but I'm not certain you are supposed to use it that way.

You can get the power pack from DIY / camping places, from £40 ish to £100 ish.  I think the more you pay the longer the battery will last.

I think the best way to do what you want is to put ice blocks in the cool box for an hour or so before you use it, and ensure that whatever you put in it has been in the fridge / freezer if possible before it goes in.

Andy
 

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<font color='#000080'>Fiona,

Let me know the make & model of your cool box. I'll try and get something knocked up from Maplins for Stoney. I'll let you know how much the parts will cost b4 purchasing them.

Dave C
 

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Fiona,

Was looking for a straight forward 12v DC transformer for you, but actually found exactly what you require so you do not have to mess around changing connectors etc.

£9.99 from maplin.  
230Vac to 12Vdc @ 1A Cigar Lighter Power Supply

Maplin

1amp should be sufficient for a cool box.

Item reference is N35AZ

HTH

Daz
 

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looks like daz has got the solution, and it's under a tenner as predicted. Fiona can you look at the coolbox, there must be a label showing how many "Watts" it uses. If daz' charger is good for 1 amp, that will drive the coolbox ok up to about 200Watts. If the coolbox is more than that, you will need a bigger charger.
 

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I'm kind of doubting my self now but should that not be 12 watts at 12v for 1amp.

Is it not w/v=a (Watts divided by volts = ampheres)

Daz  
 

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<font color='#0000FF'>Cheers Daz and Philip

sorry didn't say sooner, I have had to do some work  

looked at the Maplin website and phoned and asked them she also gave me the reference number and they were there, I just need to look at the coolbox to see if it is 1 or 2 amp.

Thanks don't know why I didn't ask before.

Fiona
 

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I have used thee fridges in the past, the instructions say they can take up to 4 hours to reach temperature which is a bit stupid for most applications.

Best to have the items chilled initialy and put in the ice packs, then use your fridge or a cool box.

James
 

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<font color='#0000FF'>Yes it does take at least 2 - 3 hours but I liked the idea of taking it away at weekends.  I hate UHT milk they give you in B & B's and like proper stuff.  

It was really purchased on a whim but I would like to use it sometime.

Thanks for the replies guys

FB
 

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[b said:
Quote[/b] (daz @ Jan. 22 2004,12:03)]I'm kind of doubting my self now but should that not be 12 watts at 12v for 1amp.

Is it not w/v=a (Watts divided by volts = ampheres)

Daz  
Cor....

Good Job I read the rest of the threat......I was just about to "suggest" a correction
 

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I'm kind of doubting my self now but should that not be 12 watts at 12v for 1amp.

Is it not w/v=a (Watts divided by volts = ampheres)

Daz  

Cor....

Good Job I read the rest of the threat......I was just about to "suggest" a correction

yes, if watts divided by volts = amperes, then watts divided by amperes = volts, if amperes = 1 then watts = volts. so for a 12V dc you're looking at 12W max. for 230v you'de be looking at 230W etc. So you're correct 12W at 12Vdc
 

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[b said:
Quote[/b] (frogkick @ Jan. 22 2004,17:20)]I'm kind of doubting my self now but should that not be 12 watts at 12v for 1amp.

Is it not w/v=a (Watts divided by volts = ampheres)

Daz  

Cor....

Good Job I read the rest of the threat......I was just about to "suggest" a correction

yes, if watts divided by volts = amperes, then watts divided by amperes = volts, if amperes = 1 then watts = volts. so for a 12V dc you're looking at 12W max. for 230v you'de be looking at 230W etc. So you're correct 12W at 12Vdc
Thank god for that....

I have been spending some time playing around with homebuild DIY diving projects based around 12v supplies and the thought of getting it wrong could have been interesting to say the least.  


I did manage to hook up 2 battery packs incorrectly on my home build 12v umbilical project (based around a standard low voltage bulb) and it was fantastically bright...  Unfortunately it was also running at 24v so I am guessing the bulb would not have lasted too long  
  It's ok to overvolt a bit and sacrifice some bulb life but I think this might have been pushing it a bit far...

Oh well you don't learn anything without experimenting, although I don't think electrics and water are the best medium to practice with....  


Daz
 

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Most of these fridges take quite a bit of current. I have one myself and I bought an adapter from Halfords which is specifically designed for the job. It was about £25 and has a cigarette lighter socket on the front and is 68W (13.8V 5A).
 

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<font color='#0000FF'>OK you guys,

The label reads For on 12V DC operation / 54W

How many amps is that if I do the calc as suggested it is 4.5amps so am I best going for the Halfords one.

Fiona
 
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