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Cell phone charger

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NadCixelsyd

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May 22, 2012, 3:48:49 PM5/22/12
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OK, I unplug my telephone from the charger and the phone gives me a
message, "To conserve energy, unplug the charger from the power
source".

I mean, how much power can the phone charger consume when it's not
charging the phone? My kill-a-watt meter doesn't register even one
watt. My guess is that the power consumption is less than 50
milliwatts (1/20 of one watt) At 50 milliwatts, that's less than 0.44
KWH per year, or about seven cents here in New England. Is plugging/
unplugging 150 times a year worth seven cents?

Les Albert

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May 22, 2012, 3:53:39 PM5/22/12
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The message is not to save you money, but to conserve energy.
How many people in the U.S. use a cell phone charger? Multiply 0.44
KWH by the number of people.

Les

danny burstein

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May 22, 2012, 3:53:52 PM5/22/12
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In the Bad Old Days (which is only five to ten years ago for
these types) the chargers were big wall warts and yes,
they could pull a watt or three when just sitting there.

The newer ones, as you noticed (and I can confirm with
my own readings) are barely readable. So it ain't worth
unplugging them from teh wall.

Now if you've got a dozen... then it kind of might make
sense to have a switchable power strip.

Also take note of hom much power they're drawing
while charging, and... how much they keep using
when the phone is charged but still plugged in.

On one of mine the phone display stays lit whenever
it's hooked up. The nightlight feature, so to epaek,
might be handy, but it's drawing two watts...

Ain't a lot, but it's a waste.


--
_____________________________________________________
Knowledge may be power, but communications is the key
dan...@panix.com
[to foil spammers, my address has been double rot-13 encoded]

Shawn Wilson

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May 22, 2012, 3:53:08 PM5/22/12
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On May 22, 12:48 pm, NadCixelsyd <nadcixel...@aol.com> wrote:

> I mean, how much power can the phone charger consume when it's not
> charging the phone?  My kill-a-watt meter doesn't register even one
> watt.  My guess is that the power consumption is less than 50
> milliwatts (1/20 of one watt)  At 50 milliwatts, that's less than 0.44
> KWH per year, or about seven cents here in New England.  Is plugging/
> unplugging 150 times a year worth seven cents?


No. Unplug your phone anyway. Overcharging will damage your
battery.

Greg Goss

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May 22, 2012, 4:17:53 PM5/22/12
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My new Nokia says the same thing. The message comes up AFTER
disconnecting the charge cable. They are clearly thinking that the
open-circuit transformer is going to burn noticeable watts when
there's no phone plugged in, and I think I agree with Nad here.

Aren't there electronics in all Li-Ion batteries that prevent
overcharging? I remember that when I got my Motorola cell phone in
1999, it warned to only use Motorola batteries because cheap imitation
batteries didn't have the charge control chip and were a severe fire
risk. That sort'a implies that all non-fire-risk batteries have the
charge control chips in them.

My previous Nokia brings up a "unplug now" message when it is happy
with the charge, but the current one and none of my previous ones
complained. I tend to ignore it, and the battery was just as good
when I stopped using it at three years as it was when new. My
previous (Ericsson) phone was a reconditioned unit that made it to
year four with me without worrying overmuch about overcharging.

On the other hand, Moria's Samsung suddenly dropped to a ten minute
talk time three hour standby level. It may have been caused by
overcharging. It was cheaper to buy a whole new identical phone and
move the battery over than to buy a new battery. Anyone want a
never-used Samsung locked to Telus with a three hour battery?
--
I used to own a mind like a steel trap.
Perhaps if I'd specified a brass one, it
wouldn't have rusted like this.

Nick Spalding

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May 22, 2012, 4:27:11 PM5/22/12
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NadCixelsyd wrote, in
<89a47e52-0e68-4f71...@d6g2000vbe.googlegroups.com>
on Tue, 22 May 2012 12:48:49 -0700 (PDT):
I always unplug mine but not for that reason. A predecessor died from
being left plugged in, or so the shop said when I went for a new one.
--
Nick Spalding

Mark Steese

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May 22, 2012, 4:29:03 PM5/22/12
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Shawn Wilson <ikono...@gmail.com> wrote in news:df098b4d-d100-4e22-947a-
2a4d05...@ra8g2000pbc.googlegroups.com:
So you deleted the paragraph where Nad explained that the message appeared
after the telephone was unplugged from the charger so you could tell Nad to
unplug the telephone from the charger? Even for you, that's eccentric.
--
The least objectionable of the inland scavengers is the raven, frequenter
of the desert ranges, the same called locally "carrion crow." He is
handsomer and has such an air. -Mary Austin

Paul Ciszek

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May 22, 2012, 7:05:18 PM5/22/12
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In article <jpgqsg$c97$1...@reader1.panix.com>,
danny burstein <dan...@panix.com> wrote:
>
>In the Bad Old Days (which is only five to ten years ago for
>these types) the chargers were big wall warts and yes,
>they could pull a watt or three when just sitting there.
>
>The newer ones, as you noticed (and I can confirm with
>my own readings) are barely readable. So it ain't worth
>unplugging them from teh wall.

On an electronics mailing list that I am on, someone posted a
"disection" of two superficially similar chargers, one from the
maker of the phone, one a cheap knockoff. The cheap knockoff
had a fraction of the guts of the name brand one--the chassis
was made to look the same, but was mostly empty. I wouldn't count
on it being "smart" enough to stop drawing AC when there was
nothing to charge.

--
Please reply to: | "We establish no religion in this country, we
pciszek at panix dot com | command no worship, we mandate no belief, nor
Autoreply is disabled | will we ever. Church and state are, and must
| remain, separate." --Ronald Reagan, 10/26/1984

David Harmon

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May 23, 2012, 8:08:21 PM5/23/12
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On Tue, 22 May 2012 14:17:53 -0600 in alt.fan.cecil-adams, Greg Goss
<go...@gossg.org> wrote,
>Aren't there electronics in all Li-Ion batteries that prevent
>overcharging?

Yes. Not getting that part right leads to the Sony Laptop Fireball
effect.
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