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Subject:Re: Laptop Power Consumption?
From:Clive Smith
Date:Sun, 17 Nov 2002 22:22:49 -0000

Using a calculator? Surely not? 12 * 3.5 is indeed 42 but thats not the
power consumption, probably the MAX

Anyway, laptops have all sorts of power reduction features, depending on
what you're actually doing at the time, even the processor steps down when
its not required. Brightness of screen. Basically, find the Amp-hour rating
of the battery and divide by the number of hours it lasts under your
required operating conditions, usually 2.5-3.5 for most laptops (assuming
your battery is in good nick and just fully charged when you start the
trial)
Then use this amperage * Voltage to estimate the power within a reasoanble
margin.

----- Original Message -----
From: "Dennis Haynes" <dhaynes@OPTONLINE.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, November 17, 2002 8:55 PM
Subject: Re: Laptop Power Consumption?

> Sorry! Fat fingers.
>
> Dennis
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
> Of Bill N
> Sent: Sunday, November 17, 2002 3:25 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Laptop Power Consumption?
>
>
> Nope again.  12 X 3.5 is 42, not 52.5.
>
> Bill
>
> ----- Original Message -----
> From: "Dennis Haynes" <dhaynes@OPTONLINE.NET>
> >
> > You got it wrong. Watts = Volts X Current. 12 X 3.5 = 52.5 watts.  16
> > X 2.6 = 41.6 Watts. Note there is a loss due to the power converter.