Could anyone please help me? I am going camping at the weekend and have a small 12v fridge (the type that holds about 4 cans and was wondering how long I could run this from the cigarette lighter socket in my Zafira before the battery goes flat?
Thanks
Phil
From my experience (I only did it once) the battery won't last overnight.
With the engine running..... until you run out of petrol ;-)
What does the little plate on the back tell you the current requirement (Amps/Watts) is?
The message from "philip woolford" contains these words:
Does it say anywhere on it how much current it draws? They're usually around 10A - which means you'll be completely unstartable in about 4 hours, maybe half that. In my experience, they're only of any use while going places - once you stop they have to as well.
Best solution is buy a bag of icecubes from Tesco.
2-3 hours.
Don't even consider running it on your car battery, it will be flat in a few hours and they are not designed to be deeply discharged. A large leisure battery should run it through the night comfortably and maybe a bit longer, depending on the actual current, and they're designed to be deeply discharged.
Greg
philip woolford ( snipped-for-privacy@tiscali.co.uk) gurgled happily, sounding much like they were saying :
It's not going to be that hot a weekend.
But if you're planning to use it whilst the car's not running, get a gas fridge.
As these things will run of wall wart type transformers/PSUs, I can't see it drawing more than an amp or so. Even so, i wouldn't risk leaving it on for more than a couple of hours unless you are checking the battery condition regularly and have a back up plan to get you started if it goes flat.
In my own car (Toyota Picnic) it is only necessary to have the key in the accessory position (required to use the CD player, or to use the ciggarette lighter) and the CD player playing for an hour or so to completely flatten the battery (without anything plugged into the lighter socket).
I doubt if it's the CD Player that flattens the battery, probably something else that comes on when it's put into the accessory position.
Mine draws 6A.....
Chris
6A/12V is 72W, so with a 240V wallwart you're only drawing under 300mA, a small one.
But for a car battery that's quite a drain (with the engine off). Almost like leaving dipped headlights on.
I've never seen a wall wart as big as 72W - not even a switch-mode one. Normally, they go to soap-on-a-rope for that kind of power.
Cheers,
Colin.
Oops, my mistake. It's better if you don't get your input and output currents mixed up...
240V/300mA *in* gives you your 12V 6A out (approximating wildly for efficiency) - which as you say is far more likely to be a reasonable size lump in a cord supply.The message from snipped-for-privacy@connectfree.co.uk contains these words:
I've just wanderd down the garden and mine's rated at 8 amps.
The message from "PC Paul" contains these words:
No - you're drawing 6A from the secondary. That's a /big/ wallwart.
Most of them draw 45W, just less than 4A. I wouldn't risk using more than
50% of the battery's rated charge, so on an average 40Ah battery, I'd use 20Ah, so say 5 hours, you may get away with a little more, but overnight your certainly going to encounter a flat battery. I've left mine for 4 hours before on a 38Ah battery with no problems. Why don't you do what I do when I go camping & get a mains hook up?MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.