Do I need a pure sine wave inverter to run a laptop?

[Spyro]

let me get this right..

take 12v, use an inverter to make it into 240v and then plug in a laptop charger that transforms it back to ~12v

What am I missing?

A few amps at the end of it. Mostly converted into heat

 

[nrbx]

Most are switched mode supplies, which should in theory be able to even take DC, so i can't think a Quasi-sine over a pure sine would matter at all.

That being said even if it shortens the life of your charger a little, the number you could buy with the saving should last you a lifetime.

 

[BabaYaga]

Does anyone know of one that has a connection that will fit a MacBook?

It seems there are some third party suppliers, for instance:

http://www.amazon.com/s/ref=bl_sr_e...TF8&node=172282&field-brandtextbin=Westronics

No idea about quality, but the price looks OK....

 

[Andrew_Fanner]

Been following this thread with interest as I have an inverter to fit (24V in, 650W continuous AC) which is intended to suport the netbook and, alhtough not at the same time, maybe the television as well.

My intention was that the netbook battery would be charged off the inverter, maybe eevn only when the engines were running, but I would only swithc the thing on and run the netbook itself off battery power. Its not helped by the fact that the battery seems to self dicharge in a week or so, which for an 18 month old pack irritates a bit.

 

[Amulet]

I used one of these for a number of years with no problems:
www.maplin.co.uk/120w-laptop-car-adaptor-44736
Far less power hungry than an inverter

I too have had perfect success with this Maplin adaptor. The voltage is configurable, and I have used it for many different laptops with different voltages. For one laptop for whose plug was not in the range supplied, I hacked a wire off a mains charger, and soldered it on to a socket that the adaptor could plug into. It seems thus that, with even a modest amount of ingenuity, it is possible to charge a Mac.

I found this to consume about half as much power as an inverter.

I have mucked about with several laptops, and all but one of them were happy with a non-sine inverter. However it did send one into spasm, with a lot of buzzing which sounded as if it was going to do something horrible if I didn't stop.

 

[nimbusgb]

Most are switched mode supplies, which should in theory be able to even take DC, so i can't think a Quasi-sine over a pure sine would matter at all.

That being said even if it shortens the life of your charger a little, the number you could buy with the saving should last you a lifetime.

Just try putting DC into a switchmode power converter!

They use the negative crossing point to stop triacs in the input stage conducting. If you put in DC there's no negative cross, triacs stay on and .......... smoke pours out of your power supply and whatever is connected to it!

 

[Csail]

Yes +1 on the 12V lighter plug converter, they are cheaper than inverters & usually come wiht lots of little plugs + variable voltage so you can use them to drive lots of DC transformer driven gimmicks. Works in your car as well

Thats what i do but we also have 4000w inverter with no probs (not pure sine wave)