laptop AC adapter tolerances

Amanda Ripanykhazov

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Dec 9, 2010, 2:35:31 PM12/9/10

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Any one know what approximate tolerances are on these things please?

I have a laptop without an adapter which takes a 19 volt 3.2 amp
adapter. I have a 20v 6.5 amp one and wonder how much damage it will
do to the laptop if I try to use it?

The unit does not have a battery to charge so this adapter will likely
be plugged in a lot of the time.

Meat Plow

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Dec 9, 2010, 2:40:52 PM12/9/10

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I've used a 90 watt 20 volt adapter on a laptop which requires 19 volts
at 55 watts for maybe 2 years now with no apparent damage. 1 volt isn't
likely to be an issue and the laptop will not consume more power than it
needs.

--
Live Fast, Die Young and Leave a Pretty Corpse

Amanda Ripanykhazov

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Dec 9, 2010, 3:20:44 PM12/9/10

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Thanks for that, I wasnt sure: I knew that the 6A wouldn't be a
problem as the unit doesn't consume any more amps than it needs but
didnt know that if it only needed 19v, the adapter wouldnt just keep
on pumping 20v into it

Meat Plow

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Dec 9, 2010, 5:13:26 PM12/9/10

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On Thu, 09 Dec 2010 12:20:44 -0800, Amanda Ripanykhazov wrote:

> Thanks for that, I wasnt sure: I knew that the 6A wouldn't be a problem
> as the unit doesn't consume any more amps than it needs but didnt know
> that if it only needed 19v, the adapter wouldnt just keep on pumping 20v
> into it

Regulation on a lot of supplies is within a volt anyway. Unless the
charging/distribution electronics of the laptop are poorly designed
I wouldn't anticipate one extra volt being any problem. I've been using
an HP 20 volt supply on a Toshiba that ran on 19 and like I said no
problems after a couple years. I'm also using a 19 volt Dell supply on an
Asus that takes 19 volts. However when measured the 19 volt supply
outputted almost 20 volts. There are no + - tolerance specs printed on
the side of the supply. If it were plus or minus 5 % that would be pretty
close to one volt either way on 19 volt output.

hrho...@att.net

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Dec 9, 2010, 5:55:46 PM12/9/10

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On Dec 9, 1:35 pm, Amanda Ripanykhazov <dmanzal...@googlemail.com>
wrote:

A tolerance of at least 10% would be reasonable, so 19.0 + 1.9 = 19.9
which is almost 20V. 20V - 2.0 V = 18V for the minimum on the 20V
supply, so you should be just fine.

Arfa Daily

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Dec 9, 2010, 8:56:08 PM12/9/10

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<hrho...@att.net> wrote in message
news:a1305490-79ac-4a35...@k30g2000vbn.googlegroups.com...

> On Dec 9, 1:35 pm, Amanda Ripanykhazov <dmanzal...@googlemail.com>
> wrote:
>> Any one know what approximate tolerances are on these things please?
>>
>> I have a laptop without an adapter which takes a 19 volt 3.2 amp
>> adapter. I have a 20v 6.5 amp one and wonder how much damage it will
>> do to the laptop if I try to use it?
>>
>> The unit does not have a battery to charge so this adapter will likely
>> be plugged in a lot of the time.
>
> A tolerance of at least 10% would be reasonable, so 19.0 + 1.9 = 19.9

That was 20.9, when I went to school ... ;-)

Arfa

Plain...@yawho.com

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Dec 10, 2010, 2:01:51 PM12/10/10

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New math.

PlainBill

Amanda Ripanykhazov

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Dec 11, 2010, 12:08:24 PM12/11/10

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On Dec 10, 2:01 pm, PlainBil...@yawho.com wrote:
> On Fri, 10 Dec 2010 01:56:08 -0000, "Arfa Daily"
>
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> <arfa.da...@ntlworld.com> wrote:
>
> ><hrhofm...@att.net> wrote in message

Actually I see the maths differently, though given the responses which
say that it is OK and has been shown to be OK over a few-year period,
the result is the same: If a laptop takes 19 volts, can I use a
converter over a prolonged period which could put out a continuous 22
volts?