Powering laptop from leisure battery

[miraz]

Hi everyone, what's the best way to run a laptop from a LB? An inverter like this?

http://www.ebay.co.uk/itm/MAINS-INVERTE ... 2eb8553196

Cheers all

[scanner]

Nope that just transforms 12v to 220/240volts and then the laptop's adaptor then transforms it back down to 19volts or whatever (mine is 19volts) which wastes energy at both stages.

I use a 12v laptop adaptor from Maplin it transforms 12v to 19v in one go and only wastes energy once.

Like this
http://www.maplin.co.uk/120w-laptop-car ... 4qodwdahpa

Be careful though I have heard that some makes (Dell being one I think) are "locked" in someway to the adaptor and 3rd party ones won't work.

[g8dhe]

You also need to be aware that most of them from 12v sources have Low-Volt Cut-out, however they tend to Cut-out a trifle to early as the cable run usually introduces a bit to much of a voltage drop and you find that they are forever switching in-out-in-out whilst your trying to use it. Make sure that you either upgrade the existing wiring in the Bongo which is a bit on the thin side or if you have a conversion make sure that the power feed to the rear is plenty adequate!

[mikexgough]

I have one of the Maplin power supplies like Scanner, but my Acer netbook I take travelling has an 8hr battery life so I don't need to use Maplin unit much. From my experience it's a good unit and I have never run it to flatten my LB and I have as Geoff advises, upgraded my power sockets, front and rear......
I don't call them cigarette lighters as most folks either don't smoke or only use the sockets for Sat Nags etc and most new cars are fitted with a power socket and a "smoking" pack is an option these days....

[francophile1947]

I agree with scanner. I use one of these http://www.ebay.co.uk/itm/12V-QUALITY-U ... 255638c9d2 and find it excellent - there are loads of others on Ebay.

[Ron Miel]

I agree with scanner. I use one of these http://www.ebay.co.uk/itm/12V-QUALITY-U ... 255638c9d2 and find it excellent - there are loads of others on Ebay.

Just bear in mind that many older laptops need more than 3.5A (66W at 19 volts) input, in which case a slightly bigger unit, such as the 120W Maplin one suggested by scanner, might be needed - or even their 150W model if you have an older laptop with a big screen and a hungry hard drive. The 120W unit is down from £29.99 to £19.99 at the moment.

[maxi_77]

The best way is with a dedicated 12V to laptop power supply, there are plenty of specific models available from specialist shops and ebay which makes matching the power plug a lot easier as well.

Do check just how much power it draws, you can use all the available power from your LB more easily than you think.

[miraz]

Thanks for all the tips guys. It's a fairly new laptop so a 100w unit should do it. I guess we'll be able to charge it while the car's running so will only hve to use the LB occasionally. Thanks again

[rapiddescent]

I use a laptop quite a lot whilst "working" in the Glenshee carpark when up there skiing. I also have a WiFi-to-3G hotspot with a roof mounted antenna to get good internet connectivity. I find that using a netbook uses a lot less energy. The hotspot has battery backup - all the kit can be found at solwise.co.uk

spent a few hours at the stuck at the A93 snow gates last year "in a meeting" !!!

[tallbongo]

Thanks for all the tips guys. It's a fairly new laptop so a 100w unit should do it. I guess we'll be able to charge it while the car's running so will only hve to use the LB occasionally. Thanks again

Although probably ok, it's best not to assume that 100W will do. Check the brick power supply for the DC voltage (often denoted by parallel solid and broken lines) and current and multiply these values. E.g. mine is 18.5V DC and 3.5A, so an inverter/adapter greater than 64.75W is required.

[mikexgough]

I checked & have the 150w version from Maplin..... with my 8hr battery netbook now....it doesn't get an awful lot of use anymore