So... who knows the answer...

Thank you. Tell me, if it _Affordable_Storage_Drawers.aspx 3.95@19 volts, would that then be like 6.25 @ 12 volts?

Cheers

Wolfie

Well on my 12v power pack it says that it is 6 amp max output and 11.5 amp max input. So you are probably right in saying that it is 6.25 amps input

This is mine

To find the current at 12V convert 19.5V and 3.95A to watts by multiplying them = 75W now to convert to current at 12V divide 75 by 12 = 6.25A.

75W is the very, very, very :) maximum power your computer will ever draw and only when _everything is working ie. the DVD drive is working, the hard disk is writing, the sound is playing at maximum volume, the microprocessor is running at maximum speed, the internal battery is flat and being charged at maximum rate, the USB ports are both in use and supplying maximum current to external devices, the mouse is moving, the display is updating at maximum frame rate etc.

In reality it's average power consumption will probably be of the order of 25W or less (2A at 12V) or less. Keep in mind that if the computer is running from _any_ external power source it thinks it's running from the mains and probably turns off all it's power saving features it would use when running from internal it's battery. Many notebooks allow you to turn power saving on when an external supply is in use - so you may wish to do that too and that will reduce average power consumption even more.

Mike Harding

"the DVD drive is working, the hard disk is writing, the sound is playing at maximum volume, the microprocessor is running at maximum speed, the internal battery is flat and being charged at maximum rate, the USB ports are both in use and supplying maximum current to external devices, the mouse is moving, the display is updating at maximum frame rate etc. "

Sounds exactly like Wolfie would be doing, meltdown here we come :)

Now... we are getting somewhere...

I have ascertained that my battery is a 14.4 @ 4000 mah... which, allowing for the rported 6 hrs. general use, makes for a consumption figure of around 0.8 A/h @ 12 volts.

Now, it is interesting that you say the Outback, which I also have, drains quickly. So, it doesn't run the system for 24 hrs.

Bugger!

The best I can come up with, is a trickle charge 20 watt panel, which will maybe not keep up.......

Bugger!

I shall now look towards plan "B".......

Oh, by the way, it's for data logging in the bush, tied in with my Canon Camera.

Cheers

Wolfie

I have never managed to get 6 hrs out of my puter on board battery even though 'mathematically' it should.

Get the notebook power pack that I use

http://www.vanson.com.hk/details/p3050.htm
it just saves all the hassles

I am guessing you also use Ozi with PhotoTool and merge the data with the photos?

Have you seen this?
http://homepages.tig.com.au/~robk/datalogger.html

Lone Wolf-
As Mike H mentined, when external power cuts out the lappys generally have features to cut down on their power usage... it may pay to invest in a timer relay that cycles on and off the power from the external batt pack- that way you still charge the batts, but use the power saving stuff in between. Generally when on battery the CPU slows itself a few cycles and panel brightness goes down. Also look at turning off any unused ports to save a little extra.

But he used to be a white guy with very blue eyes...

No No No Deep Thought said it was 42. Thats why they built the earth to ascertain the answer, and also to placate Majikthise and the other visionary.