R
Ron Sommer
What is the purpose of multiplying by .606?
R
R. McCarty
That's a good question, RMS (Root Mean Square) came to mind,
but that value is .707. Interesting thread as all those formulas and
physics fade with age and lack of use.
but that value is .707. Interesting thread as all those formulas and
physics fade with age and lack of use.
H
HeyBub
Ron said:
An AC voltage is measured peak-to-peak. Power is voltage times amperage.
Think of a sine curve. What's the AVERAGE voltage under the curve?
Another way to think of it is the 0.606 (but I think it's .707) is a
fudge-factor to make the answer come out right.
D
David Candy
..6 is average and is meaningless. .707 is RMS and reflects the shape of the sine wave (and both only apply to sine waves). In AC circuits one cannot just times EMF by current. That is for DC circuits only, in AC circuits one needs to know the impedence cos capacitive or inductive circuits shift the EMF out of phase with the current.
N
nono91
hello
For information , you will find here after some figures I mesured with an
electronic wattmeter
start pc :-------------------------------------------------- 156 w max.
pc running ( with no action )----------------------------- 125 w
simple action ( writing this message ) same !about-------125 w
playing music with windows media player---------------------- 140 w
pc
WR 450w / 2 hdd / intel celeron / no sound card ( sound module on
mother board)
/2 very small amplified speakers
regards
nono91
Lil' Dave said:
For information , you will find here after some figures I mesured with an
electronic wattmeter
start pc :-------------------------------------------------- 156 w max.
pc running ( with no action )----------------------------- 125 w
simple action ( writing this message ) same !about-------125 w
playing music with windows media player---------------------- 140 w
pc
WR 450w / 2 hdd / intel celeron / no sound card ( sound module onmother board)
/2 very small amplified speakers
regards
nono91
D
Don Schmidt
Hey folks, we're not plotting a course to the moon here, just the
approximant cost per hour to run a computer station.
PowerChute software (comes with APC UPS) reports my station consumes 268
watts.
My power rate average is 7.36¢ per kWh
(268/1000)*.0736= 1.97¢ per hour
My station comprises of:
Computer with three 10k rpm SCSI hard drives
SoundBlaster card
Adaptec SCSI card
CommShare phone switch
Actiontec DSL modem/router
Power Speakers
HP 960 Cse printer
HP 8200 scanner
Cruzer thumb drive
Sony Clie cradle
KDS power CD storage tower
Siemens 8825 Gigaset phone (needs AC power to operate)
(also have a HP CD RW, a TDK CD, DVD RW, ZIP drive and 3½" floppy drive)
Some of the items have no direct function with the computer station but all
of the above are powered by my APC Back-UPS XS 1500
(If we loose AC power, the USP will run the station for 30 minutes).
Budgeting costs: 2¢ per hour
approximant cost per hour to run a computer station.
PowerChute software (comes with APC UPS) reports my station consumes 268
watts.
My power rate average is 7.36¢ per kWh
(268/1000)*.0736= 1.97¢ per hour
My station comprises of:
Computer with three 10k rpm SCSI hard drives
SoundBlaster card
Adaptec SCSI card
CommShare phone switch
Actiontec DSL modem/router
Power Speakers
HP 960 Cse printer
HP 8200 scanner
Cruzer thumb drive
Sony Clie cradle
KDS power CD storage tower
Siemens 8825 Gigaset phone (needs AC power to operate)
(also have a HP CD RW, a TDK CD, DVD RW, ZIP drive and 3½" floppy drive)
Some of the items have no direct function with the computer station but all
of the above are powered by my APC Back-UPS XS 1500
(If we loose AC power, the USP will run the station for 30 minutes).
Budgeting costs: 2¢ per hour
D
David H. Lipman
From: "Don Schmidt" <[email protected]>
| Hey folks, we're not plotting a course to the moon here, just the
| approximant cost per hour to run a computer station.
|
| PowerChute software (comes with APC UPS) reports my station consumes 268
| watts.
| My power rate average is 7.36¢ per kWh
|
| (268/1000)*.0736= 1.97¢ per hour
|
| My station comprises of:
| Computer with three 10k rpm SCSI hard drives
| SoundBlaster card
| Adaptec SCSI card
| CommShare phone switch
| Actiontec DSL modem/router
| Power Speakers
| HP 960 Cse printer
| HP 8200 scanner
| Cruzer thumb drive
| Sony Clie cradle
| KDS power CD storage tower
| Siemens 8825 Gigaset phone (needs AC power to operate)
| (also have a HP CD RW, a TDK CD, DVD RW, ZIP drive and 3½" floppy drive)
|
| Some of the items have no direct function with the computer station but all
| of the above are powered by my APC Back-UPS XS 1500
| (If we loose AC power, the USP will run the station for 30 minutes).
|
| Budgeting costs: 2¢ per hour
|
| --
| Don
| Vancouver, USA
|
Additionally, the UPS is also consuming power.
| Hey folks, we're not plotting a course to the moon here, just the
| approximant cost per hour to run a computer station.
|
| PowerChute software (comes with APC UPS) reports my station consumes 268
| watts.
| My power rate average is 7.36¢ per kWh
|
| (268/1000)*.0736= 1.97¢ per hour
|
| My station comprises of:
| Computer with three 10k rpm SCSI hard drives
| SoundBlaster card
| Adaptec SCSI card
| CommShare phone switch
| Actiontec DSL modem/router
| Power Speakers
| HP 960 Cse printer
| HP 8200 scanner
| Cruzer thumb drive
| Sony Clie cradle
| KDS power CD storage tower
| Siemens 8825 Gigaset phone (needs AC power to operate)
| (also have a HP CD RW, a TDK CD, DVD RW, ZIP drive and 3½" floppy drive)
|
| Some of the items have no direct function with the computer station but all
| of the above are powered by my APC Back-UPS XS 1500
| (If we loose AC power, the USP will run the station for 30 minutes).
|
| Budgeting costs: 2¢ per hour
|
| --
| Don
| Vancouver, USA
|
Additionally, the UPS is also consuming power.
R
Ron Sommer
HeyBub said:
If I measure with a voltage meter, the reading will not be peak to peak.
If the reading is 110 volts, then the peak voltage would be 156 to -156.
Measuring peak to peak would be 312.
D
Don Schmidt
True but the UPS wasn't part of the problem presented. Also, power rates
here in the Pacific NW are much below the national average. The cost of the
UPS I'll chock up to insurance.
)
here in the Pacific NW are much below the national average. The cost of the
UPS I'll chock up to insurance.
)
D
David H. Lipman
From: "Don Schmidt" <[email protected]>
| True but the UPS wasn't part of the problem presented. Also, power rates
| here in the Pacific NW are much below the national average. The cost of the
| UPS I'll chock up to insurance.)
|
| --
| Don
| Vancouver, USA
|
Well you added in a scanner, printer, yada, yada ;-)
| True but the UPS wasn't part of the problem presented. Also, power rates
| here in the Pacific NW are much below the national average. The cost of the
| UPS I'll chock up to insurance.
)|
| --
| Don
| Vancouver, USA
|
Well you added in a scanner, printer, yada, yada ;-)
L
Lil' Dave
RMS, root mean square or apparent power, (.707) is an accurate
representation of power usage. Most component level technology
manufacturers use true RMS or true power (.606) factor to determine power
usage of their individual components. Reactive loads between the components
and true power usage result in apparent power usage. What you pay for at
the meter is true power. For the purposes of that, .707 is what's needed
for large power usage companies that have tariff bills. For component level
and home power usage, .606 is what's needed. The majority of home usage is
non-inductive load, like your lights. And that's what the power company
bases your bill on, a non-inductive or resistive load. Another example are
transformers and induction motors, when not energized, they're inductive.
When on, they become a resistive load. Your refigerator and AC compressor
motor are such examples and use more net energy when on. Therefore, the
resistive load is what is used for billing. We're interested, for the
purposes of this thread, in true power since that's what most of us are
paying for at the meter. Hope I made sense.
representation of power usage. Most component level technology
manufacturers use true RMS or true power (.606) factor to determine power
usage of their individual components. Reactive loads between the components
and true power usage result in apparent power usage. What you pay for at
the meter is true power. For the purposes of that, .707 is what's needed
for large power usage companies that have tariff bills. For component level
and home power usage, .606 is what's needed. The majority of home usage is
non-inductive load, like your lights. And that's what the power company
bases your bill on, a non-inductive or resistive load. Another example are
transformers and induction motors, when not energized, they're inductive.
When on, they become a resistive load. Your refigerator and AC compressor
motor are such examples and use more net energy when on. Therefore, the
resistive load is what is used for billing. We're interested, for the
purposes of this thread, in true power since that's what most of us are
paying for at the meter. Hope I made sense.
S
sensecam
The "Kill a Watt" device mentioned earlier this thread looks very good.
Can it or similar be bought in UK/Europe? (UK uses approx 240V so USA
version can't be used ). I've tried the internet search tools and the
usual uk electrical wholesalers but not found one yet. I'm also
concerened about the amount of power my PCs use.
Lyn
Can it or similar be bought in UK/Europe? (UK uses approx 240V so USA
version can't be used ). I've tried the internet search tools and the
usual uk electrical wholesalers but not found one yet. I'm also
concerened about the amount of power my PCs use.
Lyn
D
DL
S
sensecam
Thanks!
This looks really useful.
Lyn
This looks really useful.
Lyn