Some numbers on Battery Life
Dueño de Monte
after 85 days of "normal use", this mean, is 6.25% more battery life
per unit on HP50G than the battery life on HP49G+.
(Sad to say this is just one lecture and I have 20 on the HP49g+,
statistically has no difference at 95% confidence).
The only other thing I change was to run must of programs from the SD
card (now a 2 GB one) rather than read them from the flash memory,
according to some news on this group takes less energy to acces the SD
rather than the Flash Menory)
So now I don´t know if the better performance is because of the new
model or the way I ran the applications.
Hmmmm..... I need to do more tests to know (looking at the variation
on the 49 I will need 10 battery changes or 30 months to have a
significant result).
Any way its a good new to know that the HP50G "tend" to have more
battery life than the HP49G+.
Has anyone tryed to know if HP50G really has better battery life than
HP49G+? Not important issue, just curiousity ....
Daniel
david...@gmail.com
Also factor in that the 50g requires 4 AAA batteries, whereas the 49g+
requires only 3 (I believe - I've not seen one in person). I'm not an
EE, so I can't say how that would affect run time, but I CAN say how
that would affect the cost per set. :)
-Dave Britten
Michael
joules.
so you have an extra battery, then you have an extra storage cell.
4/3 more energy
this doesnt account for any possible extra power consumptions due to a
change in current draw, having said that, what i am really saying is the new
model may use more power.
this is really a side issue though, you can blister a pack of four battries
and not have to keep an eye on the battery left over, which invariably goes
in the bin.
back to the amp.
michael carey
oh did ne one watch back to the future last night.
some australian with a faulty kb
<david...@gmail.com> wrote in message
news:1192929598.2...@e34g2000pro.googlegroups.com...
Michael
show how safe windows is....
michael carey
and i know its the bios cause the setting keep changing, and yes the system
time has not changed in the last few weeks so the battery is fine.
"Michael" <mic...@bigpond.com> wrote in message
news:isySi.2449$CN4....@news-server.bigpond.net.au...
JYA
On 2007-10-21 11:19:58 +1000, david...@gmail.com said:
>> The only other thing I change was to run must of programs from the SD
>> card (now a 2 GB one) rather than read them from the flash memory,
>> according to some news on this group takes less energy to acces the SD
>> rather than the Flash Menory)
I'd be extremely surprised if that was the case...
reading from flash use nearly nothing
Michael
negating the power savings.
michael carey
"JYA" <nos...@nospam.blah> wrote in message
news:471b053a$0$26660$426a...@news.free.fr...
mats
surprise, surprise! I think Daniel was referring to this findings:
http://groups.google.com/group/comp.sys.hp48/browse_thread/thread/6dec4019c34f9786
What do you say now? ;-)
JYA
> surprise, surprise! I think Daniel was referring to this findings:
> http://groups.google.com/group/comp.sys.hp48/browse_thread/thread/6dec4019c34f9786
What
>
> do you say now? ;-)
That any analysis would state that the 50g has a power consumption
about 50% more than the 49g+ means that there are a problem in the
machine that as tested.
The 50g is pretty much identical to the 49g+ from a hardware point of view .
--
They who would give up an essential liberty for temporary security,
deserve neither liberty or security (Benjamin Franklin)
JYA
> hmm, but wouldnt the refresh still be ticking on the flash?
> negating the power savings.
Refresh?
Flash isn't SDRAM
Jean-Yves
Eric Rechlin
> That any analysis would state that the 50g has a power consumption about
> 50% more than the 49g+ means that there are a problem in the machine that
> as tested.
I saw similar results when testing on multiple calculators from different
production runs. I guess it is possible that there were problems with all
the 50g calculators that I tested, but that would surprise me.
That being said, the difference in power consumption between the SD card and
the built-in flash isn't significant enough to matter. Such a small
percentage of time is spent actually reading from SD/flash that I doubt
there would be more than a 1% or so overall difference either way.
I think the increased battery life mentioned in the original post can be
explained by either too little data to be useful, or by a use of the USB
cable (a recent post on the HP Museum forum suspected increased battery life
on the 50g, but it was later determined to be due to frequently powering the
calculator over USB).
Regards,
Eric Rechlin
J.Chen
although the 50g has more power consumption than it's predecessors,
battery packs come in 4 nowadays...
J.Chen
> > surprise, surprise! I think Daniel was referring to this findings:
> What
>
> > do you say now? ;-)
>
> That any analysis would state that the 50g has a power consumption
> about 50% more than the 49g+ means that there are a problem in the
> machine that as tested.
> The 50g is pretty much identical to the 49g+ from a hardware point of view .
>
> --
> They who would give up an essential liberty for temporary security,
> deserve neither liberty or security (Benjamin Franklin)
I concour, although power consumption is higher on the 50g than its
predecessors, battery packs come in 4 nowadays ;-)
John H Meyers
> although power consumption is higher on the 50g than
> its predecessors, battery packs come in 4 nowadays ;-)
Some also come in 12 and 24,
which is 33% more sets of 3 than sets of 4 :)
-[ ]-
J.Chen
it's still less than $1 per battery :)
Dueño de Monte
> Hi
>
This is exactly what I was trying to test ! ! ! Erick Rechlin measure
the power consumption and arrived that Flash reading consume more
energy than SD reading (very little difference) but I was trying to
confirm it.
Daniel
Dueño de Monte
Ahaaa ! You are right ! I normally make backups and some data
transfer from my PC to the HP50 so in the meantime it is not using
the battery power ! Very good explanation ! Thanks.
Daniel.
Dueño de Monte
I divide the time by the number of batteries it use ! So you can
compare the life time per battery ! I clearly know that 4 batteries
will last more than 3, but 3 batteries last a mean of 60 days of my
"normal use" (20 days per battery) and the 4 batteries las 85 days
(21.25 days per battery).
The answer is, as Erich Rechil says, HP50 last more because when it is
attach to the desktop PC, IT IS USING THE PC POWER SUPPLY, not require
the battery power at this time, so the battery last a little bit more,
even when it consume more power standing alone, the batteries last
longer.
Daniel
Rich
> hmm, but wouldnt the refresh still be ticking on the flash?
This is flash, not dynamic RAM, no refresh.
> negating the power savings.
I've not checked the numbers, and I know geometries have changed,
but I still think that larger flash RAM uses more power for reads
and writes.
Cheers,
Rich