Do y'all have free electricity there?
L. Broadfield
intelligent controllers (not to even mention those who are doing the
MP3 jukebox concept.)
Are you all on some sort of free electricity deal? (Admittedly quick
and crude) Pencil calculations indicate I'd be spending two to four
_hundred_ dollars a year to leave a PC on 24/7. (Yes, just the PC,
not the monitor.)
What am I missing here?
--Laird
Zacariah DeLesDernier
notice any significant additional cost. Are you including the monitors or
something?
Zac
Nick Stefanisko
60W light bulbs. Sort of like what many people have in a bathroom. It
doesn't cost that much to leave it on all day long. Most people don't come
close to pulling the full 250W through the power supply either. I would
guess the average HA PC only uses 100W on average throughout the day. That's
0.1kW*24h=2.4kWh at 13.5 cents per kWh that's less than 33 cents per day,
about $9.70 per month or $118 per year. $118 sounds big, but amortize that
across a year and it's pocket change. My air conditioner uses more in two
months than my PC does all year and it is not nearly as useful.
L. Broadfield wrote in message <36b2107a....@news.atmnet.net>...
Brian Karas
You only calculated for a single PC, as an example, in my house I
have:
2 Laptops (low power draw there)
2 Server PC's with SCSI arrays
2 Regular PC's (1 in the entertainment center, one in office)
2 Sun Sparc 10's
2 Sun Sparc IPX's
A handful of monitors
2 Printer/Fax machines
2 Whole-house audio amps
2 PBX's (one for work, one to bang on)
(I just noticed, I tend to be rather fond of pairs :)
1 Frame relay switch (don't ask)
And the neighbors wonder what the low 'whump-whump-whump' sound coming
from our house is :)
[] [] laird.br...@pyxiscorp.com (L. Broadfield) was saying:
>There seem to be quite a few folks out here who use their PCs as the
>intelligent controllers (not to even mention those who are doing the
>MP3 jukebox concept.)
>
>Are you all on some sort of free electricity deal? (Admittedly quick
>and crude) Pencil calculations indicate I'd be spending two to four
>_hundred_ dollars a year to leave a PC on 24/7. (Yes, just the PC,
>not the monitor.)
>
>What am I missing here?
>
>--Laird
--
Return address munged to prevent SPAM...
Automation and DataComm wiring, FAQ's, supplies, tools, etc:
http://www.FutureStandard.com
Dave Houston
minimum charge is for the months when I need the air conditioner.
"Nick Stefanisko" <nick_st...@hp.com> wrote:
>Think of it like this, a 250W power supply running at full force is like 4
>60W light bulbs. Sort of like what many people have in a bathroom. It
>doesn't cost that much to leave it on all day long. Most people don't come
>close to pulling the full 250W through the power supply either. I would
>guess the average HA PC only uses 100W on average throughout the day. That's
>0.1kW*24h=2.4kWh at 13.5 cents per kWh that's less than 33 cents per day,
>about $9.70 per month or $118 per year. $118 sounds big, but amortize that
>across a year and it's pocket change. My air conditioner uses more in two
>months than my PC does all year and it is not nearly as useful.
>
>L. Broadfield wrote in message <36b2107a....@news.atmnet.net>...
>>There seem to be quite a few folks out here who use their PCs as the
>>intelligent controllers (not to even mention those who are doing the
>>MP3 jukebox concept.)
>>
>>Are you all on some sort of free electricity deal? (Admittedly quick
>>and crude) Pencil calculations indicate I'd be spending two to four
>>_hundred_ dollars a year to leave a PC on 24/7. (Yes, just the PC,
>>not the monitor.)
>>
>>What am I missing here?
>>
>>--Laird
>
Dave Houston
http://Commander-X.com
shuf...@ichips.intel.com
$10.45 per month per computer. A typical computer might use 100-200W so adjust
your calculations accordingly...
Sam
In article <Pine.LNX.3.96.99012...@rowlf.thalamus.usit.net>,
Zacariah DeLesDernier <zaca...@rowlf.thalamus.usit.net> wrote:
> Yow, is it really that expensive? I keep 4 computers on 24/7 and I don't
> notice any significant additional cost. Are you including the monitors or
> something?
>
> Zac
>
> On Fri, 29 Jan 1999, L. Broadfield wrote:
>
> > There seem to be quite a few folks out here who use their PCs as the
> > intelligent controllers (not to even mention those who are doing the
> > MP3 jukebox concept.)
> >
> > Are you all on some sort of free electricity deal? (Admittedly quick
> > and crude) Pencil calculations indicate I'd be spending two to four
> > _hundred_ dollars a year to leave a PC on 24/7. (Yes, just the PC,
> > not the monitor.)
> >
> > What am I missing here?
> >
> > --Laird
> >
> >
>
-----------== Posted via Deja News, The Discussion Network ==----------
http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own
Joe Drogan
Your home sounds a lot like mine ...and to boot I'm a short-wave hobbyist
(talk 'bout RF!). I hate when hobbies collide but we have a lotta fun
here:)
Brian Karas wrote:
> Hehe, that's the price you gotta pay, I guess...
>
> You only calculated for a single PC, as an example, in my house I
> have:
>
> 2 Laptops (low power draw there)
> 2 Server PC's with SCSI arrays
> 2 Regular PC's (1 in the entertainment center, one in office)
> 2 Sun Sparc 10's
> 2 Sun Sparc IPX's
> A handful of monitors
> 2 Printer/Fax machines
> 2 Whole-house audio amps
> 2 PBX's (one for work, one to bang on)
> (I just noticed, I tend to be rather fond of pairs :)
> 1 Frame relay switch (don't ask)
>
> And the neighbors wonder what the low 'whump-whump-whump' sound coming
> from our house is :)
> [] [] laird.br...@pyxiscorp.com (L. Broadfield) was saying:
>
> >There seem to be quite a few folks out here who use their PCs as the
> >intelligent controllers (not to even mention those who are doing the
> >MP3 jukebox concept.)
> >
> >Are you all on some sort of free electricity deal? (Admittedly quick
> >and crude) Pencil calculations indicate I'd be spending two to four
> >_hundred_ dollars a year to leave a PC on 24/7. (Yes, just the PC,
> >not the monitor.)
> >
> >What am I missing here?
> >
> >--Laird
>
deet!
My Computer: 20w sleeping, 120w normal(1A x 120v)
Ext. HD: 8w sleeping, 96w normal (0.8A)
Zip Drive: 2w sleeping, 12w normal (0.1A)
Monitor: 15w standby, 180w normal (1.5A)
Total: 47w sleeping, 408w normal
And I would figure that my computer is awake for about 10 hours of the
day, sleeping the rest. That's roughly .4 kilowatts. Sleeping, my comp
uses rougly .047 kilowatts. So sleeping and awake combined, my comp uses
about 140 kilowatt hours per month. Which in my area figures for just
over 7 bucks a month. Which is roughly 84 dollars per year -- not too shabby.
Just for reference:
Cell phone charger: 6w
Cordless phone charger: 6w
Wall clock: 8w
Alarm clock: 4w
Personal (small) refrigerator: 108w (0.9A)
Total: 132w always, 95 kWh per month, 57 dollars per year.
This is just here in my room... i don't know about my air conditioner
though, and the calculations are rough estimates but the wattage ratings
come from the documentation and the UL plate on the device.
j
Neil Cherry
>Brian,
>Your home sounds a lot like mine ...and to boot I'm a short-wave hobbyist
>(talk 'bout RF!). I hate when hobbies collide but we have a lotta fun
>here:)
Maybe you need a CSMA/CD type scheme here (or better yet CSMA/CA :-).
>Brian Karas wrote:
>
>> Hehe, that's the price you gotta pay, I guess...
>>
>> You only calculated for a single PC, as an example, in my house I
>> have:
>>
>> 2 Laptops (low power draw there)
>> 2 Server PC's with SCSI arrays
>> 2 Regular PC's (1 in the entertainment center, one in office)
>> 2 Sun Sparc 10's
>> 2 Sun Sparc IPX's
>> A handful of monitors
>> 2 Printer/Fax machines
>> 2 Whole-house audio amps
>> 2 PBX's (one for work, one to bang on)
>> (I just noticed, I tend to be rather fond of pairs :)
>> 1 Frame relay switch (don't ask)
Different toys but similar idea.
As a practial joke one of my co-workers called my wife and posed as
the electical company and asked that Neil (me) switch over to my
internal power sources (I work for a phone company and this is a
normal request).
My poor wife was thrown for a loop at the request and told them that
they would need to speak to me when I returned.
--
Linux Home Automation Neil Cherry nch...@home.net
http://members.home.net/ncherry (Text only)
http://meltingpot.fortunecity.com/lightsey/52 (Graphics)
Bill Durocher
Broadfield) wrote:
>There seem to be quite a few folks out here who use their PCs as the
>intelligent controllers (not to even mention those who are doing the
>MP3 jukebox concept.)
>
>Are you all on some sort of free electricity deal? (Admittedly quick
>and crude) Pencil calculations indicate I'd be spending two to four
>_hundred_ dollars a year to leave a PC on 24/7. (Yes, just the PC,
>not the monitor.)
>
>What am I missing here?
>
>--Laird
I came to the same realization several months ago. After explaining
my situation to a co-worker at lunch, he gave me the following
rationalization: "The computer is converting the electricity into
waste heat. For most of the year, think of it as supplementing your
heating system."
Works for me!
-Bill
Frank Rico
Bill Durocher wrote:
I live in Florida, that realization doesn't work for me. Any other ideas,
anyone?
--
Francisco Rico, CRL
Electronic Systems Engineer
ri...@yorklock.com
(305) 672-5622 ext. 38
York Lock & Key Company
http://www.yorklock.com
David Jensen
>There seem to be quite a few folks out here who use their PCs as the
>intelligent controllers (not to even mention those who are doing the
>MP3 jukebox concept.)
>
>Are you all on some sort of free electricity deal? (Admittedly quick
>and crude) Pencil calculations indicate I'd be spending two to four
>_hundred_ dollars a year to leave a PC on 24/7. (Yes, just the PC,
>not the monitor.)
>
>What am I missing here?
>
>--Laird
Expensive PC. My calculations say:
If your PC takes 100 watts in standby, you are using 2.4 KwH per day,
that is 876 KwH per year. If your electricity is $0.10 per KwH, that is
only $87.60 a year.
Chris Arndt
under operating conditions and calculate the consumed power. I'm not sure
I've ever seen one use the full rated power of the supply.
For example, I just measured the voltage and current draw of a Dell
Pentium 100, with hard disk and a NIC, without monitor.
The supply is nameplate rated at 6 amps, 115 volts, or a whopping 690
watts. However, after booting, the computer is drawing 0.34 amps at 118
volts, or 40 watts of power. Granted, this example is on the low side,
since this particular box doen't have a lot of additional cards in it, but
it gets the idea across.
Hope this helps.
Chris
In article <36BDADDA...@herald.infi.net>,
Frank Rico <fri...@herald.infi.net> wrote:
>
>
>Bill Durocher wrote:
>
>> On Fri, 29 Jan 1999 19:52:58 GMT, laird.br...@pyxiscorp.com (L.
>> Broadfield) wrote:
>>
>> >There seem to be quite a few folks out here who use their PCs as the
>> >intelligent controllers (not to even mention those who are doing the
>> >MP3 jukebox concept.)
>> >
>> >Are you all on some sort of free electricity deal? (Admittedly quick
>> >and crude) Pencil calculations indicate I'd be spending two to four
>> >_hundred_ dollars a year to leave a PC on 24/7. (Yes, just the PC,
>> >not the monitor.)
>> >
>> >What am I missing here?
>> >
>> >--Laird
>>
russ...@my-dejanews.com
car...@slonet.org (Chris Arndt) wrote:
> Sure, here's a suggestion. Actually measure the current draw of the PC
> under operating conditions and calculate the consumed power. I'm not sure
> I've ever seen one use the full rated power of the supply.
>
> For example, I just measured the voltage and current draw of a Dell
> Pentium 100, with hard disk and a NIC, without monitor.
>
> The supply is nameplate rated at 6 amps, 115 volts, or a whopping 690
> watts. However, after booting, the computer is drawing 0.34 amps at 118
> volts, or 40 watts of power. Granted, this example is on the low side,
> since this particular box doen't have a lot of additional cards in it, but
> it gets the idea across.
How did you measure this?
Thanks,
russ...@my-dejanews.com
car...@slonet.org (Chris Arndt) wrote:
> Sure, here's a suggestion. Actually measure the current draw of the PC
> under operating conditions and calculate the consumed power. I'm not sure
> I've ever seen one use the full rated power of the supply.
>
> For example, I just measured the voltage and current draw of a Dell
> Pentium 100, with hard disk and a NIC, without monitor.
>
> The supply is nameplate rated at 6 amps, 115 volts, or a whopping 690
> watts. However, after booting, the computer is drawing 0.34 amps at 118
> volts, or 40 watts of power. Granted, this example is on the low side,
> since this particular box doen't have a lot of additional cards in it, but
> it gets the idea across.
How did you measure this?
Thanks,
RJP
John W. Lewellen
cheap laptop computer. The older generation ones still have more than
enough cpu power for home automation, they've pretty low power
consumption - especially if you turn off the screen display - and most
of them have a "low-power" standby mode for even lower power use when
not much is coming over the serial port. Another nice benefit is that
they have a built-in UPS that can last for hours. :-)
regards,
- John L.
Chris Arndt
I stripped about 3" off the outer insulating jacket of a spare PC power
cord, and used a GB digital clamp-on ammeter around the power conductor. I
measured the line voltage with a Fluke 87 True RMS DMM. If there's any
question about the current reading, I can break the line and use the
true-rms Fluke to double check it.
As a further aside, the PC drew .03 amps, or about 3.5 watts, when it was
"off"...
(I just redid the experiment with the clamp-on ammeter and a x10 coil in
the power line to reduce any low scale errors. The result are about the
same.)
In article <79nl2s$lbf$1...@nnrp1.dejanews.com>,
Zhe Zhang
the rms voltage. There is a "power factor" (PF) involved. Power = rms current *
rms voltage * PF. For computer power supplies without "power factor correction"
the PF could be as low as 0.4. Therefore, the real power is even lower than
what you measured.
Z Zhang
Chris Arndt wrote:
> Sure, here's a suggestion. Actually measure the current draw of the PC
> under operating conditions and calculate the consumed power. I'm not sure
> I've ever seen one use the full rated power of the supply.
>
> For example, I just measured the voltage and current draw of a Dell
> Pentium 100, with hard disk and a NIC, without monitor.
>
> The supply is nameplate rated at 6 amps, 115 volts, or a whopping 690
> watts. However, after booting, the computer is drawing 0.34 amps at 118
> volts, or 40 watts of power. Granted, this example is on the low side,
> since this particular box doen't have a lot of additional cards in it, but
> it gets the idea across.
>
> Hope this helps.
>
> Chris
>
> In article <36BDADDA...@herald.infi.net>,
Tim Keating
>
>
>Bill Durocher wrote:
>
>> On Fri, 29 Jan 1999 19:52:58 GMT, laird.br...@pyxiscorp.com (L.
>> Broadfield) wrote:
>>
>> >There seem to be quite a few folks out here who use their PCs as the
>> >intelligent controllers (not to even mention those who are doing the
>> >MP3 jukebox concept.)
>> >
>> >Are you all on some sort of free electricity deal? (Admittedly quick
>> >and crude) Pencil calculations indicate I'd be spending two to four
>> >_hundred_ dollars a year to leave a PC on 24/7. (Yes, just the PC,
>> >not the monitor.)
>> >
>> >What am I missing here?
Well, last time I checked my fax server, which is also my voice mail, internet gateway and
automation server. It draws around 50 watts..
.050kw/hX24hrsx365days = 438kw/hx.08$/kw= $35.04 per year.or about $3 per month.
Currently for that price,
I get peace of mind that my house will not burn down because I left the
coffee pot or iron on.
Intruders will be deterred at night.
Lights will be shut off when not in use.
Faxes answered,
Urgent voice mail messages are automaticly forwarded to cell phone.
The computer reminds my whenever I have messages by telling me every hour.
" Tim, You have unplayed messages".
The same server will soon intelligently control windows, shades, mutli-zoned hvac,
sprinklers and security system. As each system is added the old control system, will be
replaced by much newer technology which consumes a much less energy.
P.S. Some fringe benefits, If they prowl around my house day or night, they may just get a
little bit wet. :-), And a image of their sorry wet butt just might get posted on my web
site and faxed to the local police station.
Some other areas I am looking at,
reducing the phantom power each X-10 control module uses.
In the end, I expect my home automation system to save much more power than it consumes.
>> >
>> >--Laird
>>
>> I came to the same realization several months ago. After explaining
>> my situation to a co-worker at lunch, he gave me the following
>> rationalization: "The computer is converting the electricity into
>> waste heat. For most of the year, think of it as supplementing your
>> heating system."
>>
>> Works for me!
>>
>> -Bill
>
>I live in Florida, that realization doesn't work for me. Any other ideas,
>anyone?
I live in South Fflorida, and as a result, I expect to save lots of energy.
Tim Keating
ktcn...@mediaone1.net,
(Note: remove numeric digits from email address before responding.)
Tim Keating
>In article <N8Ev2.15$dv5...@news.callamer.com>,
> car...@slonet.org (Chris Arndt) wrote:
>> Sure, here's a suggestion. Actually measure the current draw of the PC
>> under operating conditions and calculate the consumed power. I'm not sure
>> I've ever seen one use the full rated power of the supply.
>>
>> For example, I just measured the voltage and current draw of a Dell
>> Pentium 100, with hard disk and a NIC, without monitor.
>>
>> The supply is nameplate rated at 6 amps, 115 volts, or a whopping 690
>> watts. However, after booting, the computer is drawing 0.34 amps at 118
>> volts, or 40 watts of power. Granted, this example is on the low side,
>> since this particular box doen't have a lot of additional cards in it, but
>> it gets the idea across.
>
>How did you measure this?
Shut off everything else at the fuse box, and look at your electric meter.
For the most part, Each revoloution of the main wheel is a calibrated to certain amount of
power consumption. That calibration number is printed on the meter.
On GE meters it's in the lower right hand corner and is usally a number like
Kh
[7.2] <-- White lettering in black box.
Which indicates that each revolution of the wheel is 7.2 watt/hours
Time the interval it takes to do one revolution and you'll get real power consumption
numbers.
DaveW3616
Dalepix
Lite4/33C; a 33 Mhz 486 with 12 Megs RAM, 9"color TFT monitor and
built-in 14.4 modem. I've run X-10 Activehome and am now looking to
switch over to Keware to use the Internet monitoring features. Have had
no problems and never worried about power consumption. Here's the
kicker, I salvaged eight of these little beauties when my company was
trashing them! (I heard that if I had moved quicker I could have had 30
more . . . day late, dollar short, story of my life)
P.S. if anyone is interested in one, let me know.
Regards,
Dale
Clayton J. Ramseyer
It costs me about $24.00 per year.
It actually will cost you more to turn your computer on and off, because
inital power up uses more power to start then levels off.
My electric bill before I got my computer was $30.00/month in my flat.
Now it is a little higher per month with the computer equipment.
I have a complete network at home multiple pcs monitors hubs and other
equipment.
One of my customers tested this theory and found that in 30 days of
turning on the computer when he needed and turninng it off when he was
finished cost him about $5.00 for the month.
Then for another 30 days leaving it on 24/7 cost him less than $2.00.
I have had similar experiences.
Try it out, you may still spend more per month than these figures but
leaving them on in my experience has been cheaper.
--
Clayton J. Ramseyer - CyberZard
cg...@bigfoot.com and/or c...@techie.com - ICQ# 2968751
"One of the worst performance of my career, and they never doubted it
for a
second." - Ferris Beuller's Day Off - Starring Matthew Broderick
JeffVolp
>
> I leave my PC on 24/7/365.
> It costs me about $24.00 per year.
>
> It actually will cost you more to turn your computer on and off, because
> inital power up uses more power to start then levels off.
There are two factors to the initial surge. One is inrush current to
charge the capacitors in the power supplies of both the computer and
monitor. That lasts a fraction of a second. The second is the higher
current used to spin up the hard drive(s), and this can last for several
seconds. Total energy used for startup would be less than one minute of
normal operation.
> My electric bill before I got my computer was $30.00/month in my flat.
> Now it is a little higher per month with the computer equipment.
>
> I have a complete network at home multiple pcs monitors hubs and other
> equipment.
> One of my customers tested this theory and found that in 30 days of
> turning on the computer when he needed and turninng it off when he was
> finished cost him about $5.00 for the month.
>
> Then for another 30 days leaving it on 24/7 cost him less than $2.00.
>
> I have had similar experiences.
>
> Try it out, you may still spend more per month than these figures but
> leaving them on in my experience has been cheaper.
Unless the computer is the ONLY load in the house, there are too many
other variables that will invalidate such a measurement:
1) Length of daylight - lights on a few minutes longer?
2) Kids home from school - TV/stereo on more?
3) Temperature - more heating or air conditioner?
You get the idea. Turning off the computer WILL save energy. How much
depends on whether you use advanced power management - monitor to sleep,
CPU clock off, hard drives on standby. If so, the power consumption
should drop to the 20 watt area in the deep sleep mode. Fully powered
it should be between 100 and 200 watts, including the monitor. Crank
the numbers.
Jeff
Karl Denninger
JeffVolp <Jeff...@worldnet.att.net> wrote:
>1) Length of daylight - lights on a few minutes longer?
>2) Kids home from school - TV/stereo on more?
>3) Temperature - more heating or air conditioner?
>
>You get the idea. Turning off the computer WILL save energy. How much
>depends on whether you use advanced power management - monitor to sleep,
>CPU clock off, hard drives on standby. If so, the power consumption
>should drop to the 20 watt area in the deep sleep mode. Fully powered
>it should be between 100 and 200 watts, including the monitor. Crank
>the numbers.
>
>Jeff
The monitor is the lion's share of power consumption of most "consumer" PCs.
Set the computer up to put the monitor to sleep (ie: shut it off) when not
in use for a few minutes. You'll find that the parasitic load from the PC
electronics alone in steady-state use is about 20W, as Jeff said.
--
--
Karl Denninger (ka...@denninger.net) http://www.mcs.net/~karl
I ain't even *authorized* to speak for anyone other than myself, so give
up now on trying to associate my words with any particular organization.
R.V.C. Tinker
-- The transients associated with turning on ANY electronic device
will shorten the life of the device. Yes - turning your PC, TV,
Stereo, etc. on and off does hurt the device each time.
-- Mechanical devices, such as your hard drive, last longer if they
are left running as well (even though most power management schemes
power down the hard drive...)
-- Depending upon WHAT your PC is doing when it is on, it could
actually compensate for its cost of operation AND save you money - in
other words:
The ability to call your home PC and tell it NOT to turn up the
heat because you are working late, or having your PC work with your
security system to turn the heat down when you leave the home and arm
the alarm system could save you hundreds of dollars a year.
(Especially on a cold or hot day when you leave for work and FORGET to
set back your thermostat.)
Having your PC be your voicemail system saves you at least
$6/month from the phone company (assuming you use their voicemail).
If you are one of the many people who leave a light on all night
(outside porch light, inside hallway light, etc.), then having the PC
turn it on and off just when needed would more than compensate since
the most common light bulb wattage is 60W, which is 50% more than the
40W that the PC consumes.
And finally, if you happen to have a way of measuring electrical
consumption (e.g. Cutler-Hammer load center, discrete measuring
devices, etc.) then you can save a TON of money if you happen to pay
extra for electricity based upon billing methodologies that increase
significantly after you reach a certain level of monthly consumption.
(e.g. As you approach the next power usage level, cut back on the
hours of operation of the pool pump to prevent you from exceeding that
next level.)
Did I forget any other examples? ;-)
Regards,
Rick
On Mon, 08 Feb 1999 16:19:57 GMT, car...@slonet.org (Chris Arndt)
wrote:
>Sure, here's a suggestion. Actually measure the current draw of the PC
>under operating conditions and calculate the consumed power. I'm not sure
>I've ever seen one use the full rated power of the supply.
>
>For example, I just measured the voltage and current draw of a Dell
>Pentium 100, with hard disk and a NIC, without monitor.
>
>The supply is nameplate rated at 6 amps, 115 volts, or a whopping 690
>watts. However, after booting, the computer is drawing 0.34 amps at 118
>volts, or 40 watts of power. Granted, this example is on the low side,
>since this particular box doen't have a lot of additional cards in it, but
>it gets the idea across.
>
>Hope this helps.
>
>Chris
>
JeffVolp
>
> There are more things to consider in this discussion:
>
> -- The transients associated with turning on ANY electronic device
> will shorten the life of the device. Yes - turning your PC, TV,
> Stereo, etc. on and off does hurt the device each time.
>
> -- Mechanical devices, such as your hard drive, last longer if they
> are left running as well (even though most power management schemes
> power down the hard drive...)
(Snip)
Hi Rick,
The turn-on reducing life is only partially true. It was certainly true
with older TVs where it seemed the number of cycles on the picture tube
filament were very limited. Anybody remember the 21AMP4? Newer picture
tubes seem to hold up much better. Power cycling stresses incandescent
bulbs. That's why they tend to die at turn-on.
The harddrive in the PC does have a limited number of start/stop cycles.
As I recall, my drive is rated for 10,000 cycles. That's 10 years at 3
cycles a day. It is a debate whether the bearing will fail sooner from
cycling or from spinning many more hours if left on.
I can't think of any reason why on/off cycles would shorten the life of
a stereo. There is an inrush current to charge the filter capacitors.
But rectifiers are typically rated for huge one-cycle surge currents. I
have to admit I had a power supply rectifier go in a TV years ago. But
I found my daughter had spilled her juice in it earlier. :-)
Jeff
Sylvan Butler
>tubes seem to hold up much better. Power cycling stresses incandescent
>bulbs. That's why they tend to die at turn-on.
>The harddrive in the PC does have a limited number of start/stop cycles.
>I can't think of any reason why on/off cycles would shorten the life of
>a stereo.
On/off cycles also cause thermal stress to components and connections
as they heat up to normal operating temperature and cool back down to
room temp. Solder joints to large components, any socketed components,
and the aluminum interconnects inside ICs are the most susceptible.
Voltage and current curves show "interesting" effects when you turn
equipment on and off. High current draw at lower voltages during
on/off cycles can cause accelerated migration of the aluminum
interconnections inside integrated circuits and transistors (mostly a
problem in motor driver/controller circuitry). Momentary voltage
overshoot as the power supply regulators start operation during powerup
can stress voltage sensitive components (not likely a problem with
well built gear but cheap consumer electronics...).
The combination of a hot monitor or TV and a quick off/on cycle can
cause the automatic degauss circuit to warp the screen inside the
picture tube. (Many monitors have a warning in the manual not to turn
off then on in quick succession.)
There are all kinds of minute effects that result in wear when
equipment is turned on and off.
There are all kinds of minute effects that result in wear when
equipment is left turned on.
Except in a few specific cases (rapid on/off cycling, when line power
is unstable, etc) it's pretty much a tossup, so do whichever you want.
sdb
--
Do NOT send me unsolicited commercial e-mail (UCE)!
Watch out for munged e-mail address.
User should be sylvan and host is cyberhighway.net.