Power consumption on PC wille off

tres_kun

tres_kun

tres_kun

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Anybody here checks the power consumption on their PC on idle and in power off status
Some numbers will be appreciated
As i have a 0.22Amp power draw on my main rig while off
0.04Amp on secondary rig
And 0.17Amp on me freenas server
 
Who me? Mine is 7w as I posted above. Doing a rough conversion the op's are:-

As i have a 0.22Amp power draw on my main rig while off = 2.64w
0.04Amp on secondary rig = 0.48w
And 0.17Amp on me freenas server = 2.04w
 
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pastymuncher said:
Who me? Mine is 0.7w as I posted above. Doing a rough conversion the op's are:-

As i have a 0.22Amp power draw on my main rig while off = 2.64w
0.04Amp on secondary rig = 0.48w
And 0.17Amp on me freenas server = 2.04w
Click to expand...

You're using 12v though, it should be 240v to calculate the power.

I've found that older PSU's built into a PC with a keyboard and mouse plugged in use about 7-9w off at the socket and the newer ones use 1-3w.

Haven't tried the power meter recently on a PC though.
 
pastymuncher said:
How do you reckon that? Power meter says 0.05A/0.7w for my pc. If I used 240v instead of 12v for the op's his main pc would be pulling 52.8w with the system turned off.
Click to expand...

Well, what voltage does your PC pull in from the wall? It's not going to be 12v, so some of the readings are off or it's not being read as we're assuming it to be (from the wall).
 
exactly my point power consumption is off its rocks
need better hardware to test
but i am able to light up a 240V light bulb in series with the PC while it is off
so a lot of power

from the wall using a multimeter in series with the PC set on Amps
so no confusion there
my voltage is 243V at soket
 
define what you mean by off, so you chopped up the power lead to connect a light bulb in series, ditto for the multi-meter.
Most people would use a clamp or plugin meter to measure the power / current.
 
will get a plugin watt meter
i wonder if it will be of any good
10% tolerance will be ok with me
as long as it tells me with some accuracy what is going on
and yes i have cut the kettle pug and fixed the wires in a terminal stripe
 
Measuring current alone will not tell you what the power consumption is because PCs have a power factor less than one. A lot less than one when off. If you just multiply current * voltage you get apparent power, in VA (volt-amps). You need to multiply by the power factor to get real power in W (watts).

Is "off" with the switch on the back of the PSU on or off? If the switch is off then only the input filter will be drawing current. If it's on and the PSU is older, then a lot of its circuitry could still be drawing power.

Input filters typically place a 0.1µF "X" capacitor across live and neutral, which with the UK's 250V@50Hz will draw about 0.008A, which gives an apparent power of 2VA. That's about what I would expect most PCs to draw when the PSU is switched off (my power meter says 3VA for my desktop machine, with an unknown accuracy and 1VA precision). If one was drawing 0.22A when switched off, that would imply an X capacitor of about 3µF, which is extremely big, although not unheard of.

tres_kun said:
...i have cut the kettle pug and fixed the wires in a terminal stripe
Click to expand...
I would strongly recommend against using terminal strip like that. It only takes a little force to accidentally pull the wires out, then you have a live wire flapping about.
 
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moogle said:
Well, what voltage does your PC pull in from the wall? It's not going to be 12v, so some of the readings are off or it's not being read as we're assuming it to be (from the wall).
Click to expand...


I have a plug in power meter pluggeed into the wall mains socket. Plugged into that is my pc and monitor, both on a surge protection extension. The amps/wattage I posted is what the power monitor says my pc/monitor is drawing with them shut down.

I did get the Amps correct but the wattage was what I correctly posted in the first place 7w and not 0.7w which is somewhere around what would be expected from a shut down system. There was a speck of dust between the 0 and the 7 which I wrongly took to be a decimal point.
 
well i am pleasantly surprised
the watt meter is reading 1W from the PC while off
the amperage is read as 0.21Amps but Wats as 1W
Have tested with a 0.85Amp phone charger and reads consumption of 4Watts
It is time to retire from electronics or get a guru to explain the reason

thank you all
 
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