Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Dale wrote: Mike Williams wrote: On Thursday 03 August 2006 19:27, James wrote: The simplist solution is NOBODY puts a 240 VAC power supply into a computer unless it's going to draw some serious current (amps) thus by the nature of it being 240 VAC, you already know it is a power hog. Now, I'm not electrical engineer, but I know my way around a fuse board and electricity having fitted out both our new offices for power, network, and some walls. In the UK, and most (if not all) of Europe, Africa, and Asia too, run on about 240 volts, 230 +-10% I think now. Pretty much the whole world, except the Americas. Well, the USA has the same coming in too. We have 220v to 240v coming in but that is split into different legs for the 110v to 120v stuff. Unless those two legs are in phase, you're still only getting 110V-120V AC. IIRC (And it's from 20 years ago I'm working here) it's not, it's just two legs of the 3 phase generated power. Which means they're 120 deg out of phase, and so you still only get 110-120V. In order to get 220-240V, you'd need 3 phase power. I suspect you get two 110V lines because of current limitations. Not to provide you with 220V which you'r enot going to get from just adding two out of phase lines. (Unless of course the US has wired up two in-phase separate 110V lines. In which case you can get 220V outof it, but I seem to remember a lecture in Eng Sci saying it was common to take 2 of 3 phases to a house in the US alternate which 2 between successive houses. If you are using transformers to reduce it from 220v to 110v, that will waste some energy right there. Transformers are not real efficient. If you touch it and it is warm, that is what you are wasting. That will also make whatever you are cooling with work harder too. Plus you need twice the current at 110V vs 220V. (Volts are big 'V' BTW! Named after Voltaire). This means higher line losses as loss is proportional to current. Higher line losses mean that cable length becomes more of a problem. (A 10V drop in 240V is less than 5%. 10V drop in 120V is almost 10%. Much more significant). All-in-all I prefer 240V single phase. H -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.2 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFE3Ew5/3QXwQQkZYwRAlYaAJsGe3RCLAgWO6knje/rWXwD6S0irQCfcgsO bkdH6utTMuvNYMUJ+5mEJmc= =/bVW -END PGP SIGNATURE- -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
On Friday 11 August 2006 11:22, Hamish Marson wrote: Dale wrote: Mike Williams wrote: On Thursday 03 August 2006 19:27, James wrote: The simplist solution is NOBODY puts a 240 VAC power supply into a computer unless it's going to draw some serious current (amps) thus by the nature of it being 240 VAC, you already know it is a power hog. Now, I'm not electrical engineer, but I know my way around a fuse board and electricity having fitted out both our new offices for power, network, and some walls. In the UK, and most (if not all) of Europe, Africa, and Asia too, run on about 240 volts, 230 +-10% I think now. Pretty much the whole world, except the Americas. Well, the USA has the same coming in too. We have 220v to 240v coming in but that is split into different legs for the 110v to 120v stuff. Unless those two legs are in phase, you're still only getting 110V-120V AC. IIRC (And it's from 20 years ago I'm working here) it's not, it's just two legs of the 3 phase generated power. Which means they're 120 deg out of phase, and so you still only get 110-120V. In order to get 220-240V, you'd need 3 phase power. Safer to use a transformer 110V-220V which will lessen the danger of playing with two or three live wires, a misconnection can cause an outage with all sorts of problems generated, died disks and other apparatus. I suspect you get two 110V lines because of current limitations. Not to provide you with 220V which you'r enot going to get from just adding two out of phase lines. (Unless of course the US has wired up two in-phase separate 110V lines. In which case you can get 220V outof it, but I seem to remember a lecture in Eng Sci saying it was common to take 2 of 3 phases to a house in the US alternate which 2 between successive houses. If you are using transformers to reduce it from 220v to 110v, that will waste some energy right there. Transformers are not real efficient. If you touch it and it is warm, that is what you are wasting. That will also make whatever you are cooling with work harder too. Plus you need twice the current at 110V vs 220V. (Volts are big 'V' BTW! Named after Voltaire). Sorry, the french writer Voltaire was not dabbling in science. It was Alessandro Guiseppe Antonio Volta who detected the reaction of different metals on the muscles of a hindlegs of a frog and build the first electric battery from that detection. This means higher line losses as loss is proportional to current. Higher line losses mean that cable length becomes more of a problem. (A 10V drop in 240V is less than 5%. 10V drop in 120V is almost 10%. Much more significant). All-in-all I prefer 240V single phase. So do I, although in itself that voltage is deadly -- Herman Grootaers -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
Hamish Marson wrote: Dale wrote: Mike Williams wrote: On Thursday 03 August 2006 19:27, James wrote: The simplist solution is NOBODY puts a 240 VAC power supply into a computer unless it's going to draw some serious current (amps) thus by the nature of it being 240 VAC, you already know it is a power hog. Now, I'm not electrical engineer, but I know my way around a fuse board and electricity having fitted out both our new offices for power, network, and some walls. In the UK, and most (if not all) of Europe, Africa, and Asia too, run on about 240 volts, 230 +-10% I think now. Pretty much the whole world, except the Americas. Well, the USA has the same coming in too. We have 220v to 240v coming in but that is split into different legs for the 110v to 120v stuff. Unless those two legs are in phase, you're still only getting 110V-120V AC. IIRC (And it's from 20 years ago I'm working here) it's not, it's just two legs of the 3 phase generated power. Which means they're 120 deg out of phase, and so you still only get 110-120V. In order to get 220-240V, you'd need 3 phase power. I suspect you get two 110V lines because of current limitations. Not to provide you with 220V which you'r enot going to get from just adding two out of phase lines. (Unless of course the US has wired up two in-phase separate 110V lines. In which case you can get 220V outof it, but I seem to remember a lecture in Eng Sci saying it was common to take 2 of 3 phases to a house in the US alternate which 2 between successive houses. The two lines are out of phase. Here, big things like air conditioners, stoves, dryers and central heat run off the 220 or 240v wires. Small things like lights, hair dryers, fans and even small window air conditioners run off the 110 or 120v lines. In most places here, 3 phase is not available unless you are in a area that has large factories or are in a city. Here the black and white wires are 120v, the red and black wires are 220 or 240v. Also note, you can tell the power company which one you want when you get them to put up your pole. We had 220v for years. When the transformer went out I asked for 240V. With a light load we actually get about 248v or so. When something like the A/C turns on it will drop to about 240v or so. It stays pretty stable after that though. Keep in mind that light bulbs blow faster at the higher voltage. At the same time A/C compressors run a lot more efficient. If you are using transformers to reduce it from 220v to 110v, that will waste some energy right there. Transformers are not real efficient. If you touch it and it is warm, that is what you are wasting. That will also make whatever you are cooling with work harder too. Plus you need twice the current at 110V vs 220V. (Volts are big 'V' BTW! Named after Voltaire). This means higher line losses as loss is proportional to current. Higher line losses mean that cable length becomes more of a problem. (A 10V drop in 240V is less than 5%. 10V drop in 120V is almost 10%. Much more significant). All-in-all I prefer 240V single phase. H As far as being efficient with power usage, me two. I have a friend that uses some heavy equipment and some of them are 480v. They put out a lot more horsepower but they run very cool because the current draw is so small. We here would likely be better off if we did use 220v like other countries but it would take us years to convert things over. Dale :-) -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
Herman Grootaers wrote: On Friday 11 August 2006 11:22, Hamish Marson wrote: All-in-all I prefer 240V single phase. So do I, although in itself that voltage is deadly When combined with a high enough current... -- Naga -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
On Fri, 2006-08-11 at 12:24 +0200, Nagatoro wrote: Herman Grootaers wrote: On Friday 11 August 2006 11:22, Hamish Marson wrote: All-in-all I prefer 240V single phase. So do I, although in itself that voltage is deadly When combined with a high enough current... The current drawn through a conductor (in this case a live body) is determined by the voltage, and the resistance of the body itself. Basic, elementary Ohms law. A live body will draw something in the order of 100 mA from 240V ac (assuming the power source can deliver that current, we can assume it will as this is mains after all). The point is that even if the power station can generate 14 brazillion quadrillion amps and the wires to your house can carry it without melting, you will still only have 100mA going through your body if you happen to get shocked. The power source delivers the volts and th4e sink doesn't get to change that. The sink draws the current and the source doesn't get to change that. alan -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
On Fri, 2006-08-11 at 13:44 +0200, Naga wrote: On Friday 11 August 2006 13:26, Alan Mckinnon wrote: The current drawn through a conductor (in this case a live body) is determined by the voltage, and the resistance of the body itself. And in this case the surface that the body is in contact with. I other words don't stand in water when you get the shock (but rubber shoes should work) :) On a side note, when I was still fixing things for a living I used to demonstrate to new trainees how current flow actually worked by deliberately touching the mains live on a running tv set in complete safety. Very very very few of them figured it out :-) The secret: - use one finger of one hand - wooden workbench - shoes alan -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
On 8/11/06, Dale [EMAIL PROTECTED] wrote: We here would likely be better off if we did use 220v like other countries but it would take us years to convert things over. Yep, and we would have to start by converting to plugs that didn't encourage us to electrocute ourselves every time we plug in our laptops! -Richard -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
On Fri, 2006-08-11 at 15:07 -0700, Richard Fish wrote: On 8/11/06, Dale [EMAIL PROTECTED] wrote: We here would likely be better off if we did use 220v like other countries but it would take us years to convert things over. Yep, and we would have to start by converting to plugs that didn't encourage us to electrocute ourselves every time we plug in our laptops! coming from a country where you have to explicitly switch on the plugs just so that electricity _will_ flow, seeing the US styled plugs really frigthens me. I wonder how this passed through OHSA inspections. -- Ow Mun Heng [EMAIL PROTECTED] -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
On Thu, 2006-08-03 at 20:58 -0700, Ow Mun Heng wrote: On Fri, 2006-08-04 at 13:20 +0930, Iain Buchanan wrote: They're great devices - you can often buy a multimeter (every geek should have one :) with a current clamp (or transducer) thrown in. That way you have no wiring, no inline plugs, and you won't even have to turn the PC off to install it! Dang. I have to kick myself for calling myself a Geek. yeah, I have sore shins too... Here's one that is just a current clamp [fluke.com.au]: http://www.fluke.com.au/auen/products/Fluke+320.htm?catalog_name=FlukeAustralia but you can buy a normal multimeter with the option too... Hmm.. How does it work? Perhaps a google search or go through howstuffswork.com would help. how does it work or how do you use it? You use it by clipping the claws around one wire that you're interested in... um, I just came across a problem - it won't work with an AC power cord, because you have active and neutral both going through the clamp in opposite directions, hence they'll cancel each other out. You need only the active going through the clamp... oh well, it was a nice idea. But how it works (with AC) is something like this: AC produces a field around the wire as it flows. This field in turn will induce a current in a wire placed close to it. Loop a wire (transducer) around another wire (AC current flow), and you can inference the change in current in the original wire by measuring the current flow in the loop. It doesn't work with DC, as DC doesn't create a field (at least, not when it's steady. When switching on and off a DC device, you'll still get a change in current) IANAE(lectrician), so this might be complete bunkum, but that's how I remember it anyway. HTH, -- Iain Buchanan iaindb at netspace dot net dot au Truth is free, but information costs. -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
Remy Blank wrote: Iain Buchanan wrote: um, I just came across a problem - it won't work with an AC power cord, because you have active and neutral both going through the clamp in opposite directions, hence they'll cancel each other out. You need only the active going through the clamp... Or only the neutral. It doesn't matter, actually. But how it works (with AC) is something like this: AC produces a field around the wire as it flows. This field in turn will induce a current in a wire placed close to it. Loop a wire (transducer) around another wire (AC current flow), and you can inference the change in current in the original wire by measuring the current flow in the loop. It doesn't work with DC, as DC doesn't create a field (at least, not when it's steady. When switching on and off a DC device, you'll still get a change in current) IANAE(lectrician), so this might be complete bunkum, but that's how I remember it anyway. You almost got it. Actually, it's not necessary that the current be AC: even a DC current produces a magnetic field around the conductor (albeit a DC field). The clamp is a ferromagnetic ring that concentrates the magnetic field, and it is interrupted at one location by a hall-effect sensor that measures the magnetic field. The current can be calculated from the magnetic field intensity and the diameter of the clamp ring. -- Remy Remove underscore and suffix in reply address for a timely response. Well you almost got it right. The clamp is just a basic transformer being the secondary winding. Since AC current flow changes both in amplitude and direction, induces a current flow in the secondary winding, the clamp. The current is then rectified and the measurement then is displayed on a meter. I've used high voltage transformers from old monitors to monitor and trigger alarms signaling excessive current change. Basically just a home made clamp. Cheers. -- Ted Ozolins(VE7TVO) Westbank, B. C -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
On 8/3/06, Ow Mun Heng [EMAIL PROTECTED] wrote: On Thu, 2006-08-03 at 18:27 +, James wrote: Ow Mun Heng Ow.Mun.Heng at wdc.com writes: I know this is VERY OT. I have a Gentoo Server running at Home 24/7 and there's a possiblity that it's really eating up my energy bill. I've seen the Kill-A-Watt http://www.thinkgeek.com/gadgets/electronic/7657/ but it's a 120V US Version. I'm looking for a 240V Version. Would anyone here know where to get one? The Server is an old DELL PowerEdge 4300 w/ 2x350Mhz Procs and 1GB Mem If you have an electrician, or are reasonably knowledgable with electricity, then you can split off one of the hot legs run it thru your 120VAC power meter an see how much juice (energy) you are using. I'm not going that path. Thanks anyway for the Howto. Another, better solution is to purchase a clamp/amp meter so you can merely put it around the power cord and make all sorts of power The item I want to test is back home. I'm in the US for a few months only, so a 240V one is needed. The simplist solution is NOBODY puts a 240 VAC power supply into a computer unless it's going to draw some serious current Unfortunately, I'm not a US resident and I live in a Country where the power comes in at 240V. energy savings in a year or so. Big power supplies also throw off lots of heat, so if you live somewhere hot, it's a double wammie. Yeah.. Asian Country. HOT throughout the year. I live in a cowntry where energy comes at 240V (Brazil), but all computers, printers and most eletronic devices are wired to a voltage stabilizer that reduces the risk of damage by lightning and other voltage peaks. This stabilizers also transform 240 to 120V AC, so, our energy is 240V but almost ALL devices run switched to 120V. So, my advice is: get a stabilizer. -- Daniel da Veiga Computer Operator - RS - Brazil -BEGIN GEEK CODE BLOCK- Version: 3.1 GCM/IT/P/O d-? s:- a? C++$ UBLA++ P+ L++ E--- W+++$ N o+ K- w O M- V- PS PE Y PGP- t+ 5 X+++ R+* tv b+ DI+++ D+ G+ e h+ r+ y++ --END GEEK CODE BLOCK-- -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
On Thu, 2006-08-03 at 16:04 -0300, Daniel da Veiga wrote: On 8/3/06, Ow Mun Heng [EMAIL PROTECTED] wrote: Unfortunately, I'm not a US resident and I live in a Country where the power comes in at 240V. I live in a cowntry where energy comes at 240V (Brazil), but all computers, printers and most eletronic devices are wired to a voltage stabilizer that reduces the risk of damage by lightning and other voltage peaks. This stabilizers also transform 240 to 120V AC, so, our energy is 240V but almost ALL devices run switched to 120V. I'm sorry but what's the difference between running it at 120V or 240V? (besides the stabilizer) BTW, my PC equipment is running off an APS UPS that does power surges and I presume stabilizer as well. -- Ow Mun Heng [EMAIL PROTECTED] -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
Mike Williams wrote: On Thursday 03 August 2006 19:27, James wrote: The simplist solution is NOBODY puts a 240 VAC power supply into a computer unless it's going to draw some serious current (amps) thus by the nature of it being 240 VAC, you already know it is a power hog. Now, I'm not electrical engineer, but I know my way around a fuse board and electricity having fitted out both our new offices for power, network, and some walls. In the UK, and most (if not all) of Europe, Africa, and Asia too, run on about 240 volts, 230 +-10% I think now. Pretty much the whole world, except the Americas. Well, the USA has the same coming in too. We have 220v to 240v coming in but that is split into different legs for the 110v to 120v stuff. If you are using transformers to reduce it from 220v to 110v, that will waste some energy right there. Transformers are not real efficient. If you touch it and it is warm, that is what you are wasting. That will also make whatever you are cooling with work harder too. Dale :-) :-) -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
On 8/3/06, Dale [EMAIL PROTECTED] wrote: Well, the USA has the same coming in too. We have 220v to 240v coming in but that is split into different legs for the 110v to 120v stuff. No, we don't. We have ~120V between a 'hot' wire and neutral, and 240V appliances work by using the two hot wires that are 180 degrees out of phase with each other. Other countries actually have 240V between the hot and neutral wires, regardless of how many hot wires actually come in. -Richard -- gentoo-user@gentoo.org mailing list
Re: [gentoo-user] Re: [Very OT] - Kill-A-Watt (240V Version) to measure my Gentoo Server Power Usage
Richard Fish wrote: On 8/3/06, Dale [EMAIL PROTECTED] wrote: Well, the USA has the same coming in too. We have 220v to 240v coming in but that is split into different legs for the 110v to 120v stuff. No, we don't. We have ~120V between a 'hot' wire and neutral, and 240V appliances work by using the two hot wires that are 180 degrees out of phase with each other. Other countries actually have 240V between the hot and neutral wires, regardless of how many hot wires actually come in. -Richard But I can plug their 220v stuff in here too. I have seen the plugs here, Lowes I think. They are funny looking though. That said, having it 220 or 240v is more efficient. That is why they distribute power at higher voltages, sometimes as high as 500Kv. Dale :-) :-) -- gentoo-user@gentoo.org mailing list
