12V Socket Overload

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gooner677
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12V Socket Overload

Post by gooner677 »

Hi,

Looking for advice from all the car electrics experts.

How many things can a 12V socket have plugged into it? After you have the satnav, fridge, phone charger, DVD players for kids (even after the shtf they will still be a pain on a journey more than an hour).

Assuming there must be a limit to the amount of power being drained from 1 socket?

Thanks
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Yorkshire Andy
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Re: 12V Socket Overload

Post by Yorkshire Andy »

Depends on the car usually 15 to 20a max which is about 150w see your handbook fuse section NEVER Fit a larger fuse than spec

Plenty of free converters on line if you can't. Get Your head round the v=I/R formula triangle
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Yorkshire Andy
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Re: 12V Socket Overload

Post by Yorkshire Andy »

PS also be aware any multi socket adaptors might have a lower rating than the car so derate Accordingly
If your roughing it, Your doing it wrong ;)

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Briggs 2.0
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Re: 12V Socket Overload

Post by Briggs 2.0 »

Erm....I'm sure it's a typo but V=IxR, not V=I/R.

The formula you need to consider is Power = Volts x Amps, or P=IV.

If you can tot up the total power consumption of all your attached devices you can work out the total current (amps) they will draw from the battery, via the 12V socket. As Andy said, most 12V car outlets will be on a 15 Amp fuse, you can check that in the manual. Another thing to consider is how quickly all these items will drain the battery when the engine is off.
Last edited by Briggs 2.0 on Mon Apr 28, 2014 9:15 am, edited 1 time in total.
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Plymtom
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Re: 12V Socket Overload

Post by Plymtom »

Yes Brigs pipped me to the post but as an electrician I can tell you you're right Briggs
Yorkshire Andy wrote:Depends on the car usually 15 to 20a max which is about 150w see your handbook fuse section NEVER Fit a larger fuse than spec

Plenty of free converters on line if you can't. Get Your head round the v=I/R formula triangle
I think you may mean the P=I xV or 15-20 x 12 so 180-240W, having said that if we are talking ciggy lighter sockets I would be wary, the original design required high power to generate the heat, but to draw it continuously may be a little much to expect from the socket, the plug, or the cars system as a whole (battery/alternator etc).
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Yorkshire Andy
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Re: 12V Socket Overload

Post by Yorkshire Andy »

If your roughing it, Your doing it wrong ;)

Lack of planning on your part doesn't make it an emergency on mine
hawkafr

Re: 12V Socket Overload

Post by hawkafr »

It also depends on the amp rating of the wiring of the socket ie 10amp or 15amp
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gooner677
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Re: 12V Socket Overload

Post by gooner677 »

So really the best option would be install a second battery and have the fuse/power set up similar to the 12v system on a caravan or camper van. This would be an option as I am thinking of investing in a small campervan sized vehicle.

I miss the multi 12v socket system on the galaxy and similar cars. Allowed for a lot more scope.

Thanks
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Hamradioop
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Re: 12V Socket Overload

Post by Hamradioop »

I would assume a 10 amp max on a cigarette lighter socket, as the manufacturer will keep cost down using cheapest wire etc.
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