"Can" Inverter for Laptop charging

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Nigel_Ward

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\"Can\" Inverter for Laptop charging

I am considering a Ring 150w can inverter (from Halfords) to recharge my laptop in the car and on the boat. It is only to recharge rather than run the laptop continuously.

This is only a modified sine wave inverter, but do they work? I have an Acer laptop.

Any positive or negative comments welcome.
 
Re: \"Can\" Inverter for Laptop charging

I've used modified sine wave inverters and had mixed success - some chargers work and some don't - and doesn't matter if you are using the laptop or not. - You will have to try and see, or get a pure sine wave inverter (at very high cost).
 
Re: \"Can\" Inverter for Laptop charging

It might be worth investing in a 300w one, which gives a little more latitude to the demand. I found that the can inverter would not run a very small LCD TV.

I have rewired my cig lighter sockets now with heavier cables. I was surprised at the drop in voltage on the originals at just 5 amp loading!
 
Re: \"Can\" Inverter for Laptop charging

150W is too small. Because of the power loss in the inverter it won't run the laptop and charge it, which means taking out the battery - a bit of a pain. Try this one (half the price of Maplins). I've had stuff from them before and found it excellent quality.

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Re: \"Can\" Inverter for Laptop charging

[ QUOTE ]
150W is too small. Because of the power loss in the inverter it won't run the laptop and charge it, which means taking out the battery - a bit of a pain.

[/ QUOTE ]
Rather depends on the laptop!!

I have the LiteOn charger for my Acer laptops and the larger is rated at 3.42amps at 19v which is only 65w ... even allowing for a little bit of loss there is plenty of overhead in a 150w can inverter...
 
Re: \"Can\" Inverter for Laptop charging

As a point of interest, for many years now I've sought out and used laptops that can plug directly into the 12v system just to avoid the use of inverters. Always felt that it was poor use of precious battery energy.

Currently have 3 which all happen to be Toshibas but I'm sure there must be others. If the mains power supply output is rated at up to 15v then they seem to work perfectly well. An IBM rated at 16v didn't work. Most modern units seem to work ~20v, but that means the ones I use come for about £30 2nd hand, but will support charts etc no problem.

Nudge
 
Re: \"Can\" Inverter for Laptop charging

[ QUOTE ]
As a point of interest, for many years now I've sought out and used laptops that can plug directly into the 12v system just to avoid the use of inverters. Always felt that it was poor use of precious battery energy.

[/ QUOTE ] I've often wondered why they aren't all 12V. It is slightly easier to go from a higher voltage to the various voltages needed in a laptop but I wouldn't have thought there would be that much difference.
 
Re: \"Can\" Inverter for Laptop charging

I had a low power inverter that I used for charging a laptop, the laptop wouldn't boot from just the inverter but it charged the batteries ok, so the trick was to boot from the batts then plug in the inverter and presto unlimited playing time.
 
Re: \"Can\" Inverter for Laptop charging

Thanks for the useful replies.

I would have preferred an Acer genuine part but cannot find one, so will probably go for the larger size inverter.
 
Re: \"Can\" Inverter for Laptop charging

I have a Dell charger that gets very hot on modified sine. After using it on modified sine for some time it failed. I will never, ever run electronics from anything other than pure sine, now.

The problem is that there are interference filters on the mains input, inside the power supply block. The purpose of those filters is to absorb noise from the mains, and from the dc-dc converter in the power supply so that the equipment neither suffers from noise, nor causes a noise problem for others.

In a pure sine wave, 100% of the energy is in the fundamental -- in the UK, 50Hz. In a square wave, of 50Hz, a huge amount of energy is in the odd harmonics -- 150 Hz, 250 Hz, 350 Hz, ..... for ever. All of the energy above 50 Hz is absorbed by the filters in the power supply and it CAN get hot as a result. A modified sine wave might have a much closer waveform and fewer harmonics, but I have never seen it specified on any 'can inverter' -- or any other inverter that a yachtie might buy.

So if you use anything other than a sine wave inverter you have a risk. Your risk. Your choice. Some work fine. Some blow up. If you look at your equipment, you will probably see a sine wave sign by the input...this tells you that it designed to work with sine waves. Not, necessarily, with modified sine waves or square waves.
 
Re: \"Can\" Inverter for Laptop charging

[ QUOTE ]
As a point of interest, for many years now I've sought out and used laptops that can plug directly into the 12v system just to avoid the use of inverters. Always felt that it was poor use of precious battery energy.

Currently have 3 which all happen to be Toshibas but I'm sure there must be others. If the mains power supply output is rated at up to 15v then they seem to work perfectly well. An IBM rated at 16v didn't work. Most modern units seem to work ~20v, but that means the ones I use come for about £30 2nd hand, but will support charts etc no problem.

Nudge

[/ QUOTE ]

I have found IBM Thinkpad, Acer, Maxdata, Tosh, HP, Compaq, Asus all work of 12V direct. Can't remember which one - but one needed battery in at start to add to voltage in to get it to actually start up.
Trick is to remove the battery so that power is not charging as well. Then you find that majority are actually happy on 12V - the excess is battery charging. Doesn't seem to matter whether it's a 16V IBM or a 19V Tosh ...

For running with battery in and to charge - I uses Maplins DC - DC adaptor. But note that running CD's, add-ons up the power need and on one machine I have that has external floppy, CD etc. - the power req't can actually near stop charging to battery. USB GPS and other items all increase the power demand ... 150W is minimum but useable IMHO.
 
Re: \"Can\" Inverter for Laptop charging

Worked on one of my computers and buggered another. It went into spasm tripping between on and off charge.

It's better to get a 12 volt charger for the computer from (say) Maplin . This will plug int a lighter socket and can be set to the right voltage/polarity for your computer. Comes with most types of plugs. I measured amps, and it was twice as efficient as stuffing the juice through an inverter.

Better for most modern computer batteries to plug in constantly.

Remember to set your power profile on the laptop to some kind of lean and mean regime. It thinks it's on mains and will, by default, adopt a greedy regime. Spin down disks, dim screen and turn off CD drive, for example.
 
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