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From: Adam on 10 Oct 2007 20:25 Peter D. wrote: > There are lots of strange little devices in a modern home. VCRs have > a dew protection system in them, rather than risk the damage that dew > can cause they will quietly turn on a small heater when needed. Do > you have any battery backed devices that recharge when they think it > is a good idea? Shaver, clock, UPS, burgler alarm, smoke detector, > mobile phone, bilge pump, electric blanket, etc. Hmm. Could have been the VCR's heater. The only things here with rechargeable batteries (electric razor, cell phone, Ni-Cd/Ni-MH household battery charger) weren't plugged in. Thanks, Peter, for your refresher course in "real power" and "imaginary power" and "power factor." I'd forgotten whatever I knew about those. > It is usually not worth > the effort in an ordinary home, but adding an extra capacitor or > inductor to balance out the existing reactive load so that the > whole thing appears to be resistive can minimise your bill in > special circumstances. Remember that you would have to re-tune > the device every time you turned anything on or off. Just curious... would it be possible, in theory, to build a gadget that would plug into a household electric outlet and automatically switch in inductors or capacitors as needed? The idea being it would automatically bring the power factor closer to one, for the household or at least that one circuit, and save some money. Robert M. Riches Jr. wrote: > If Adam is in the US, at least in theory the meter installed > by the electric utility is _supposed_ to properly measure > real power and disregard reactive (imaginary) power. If I > remember correctly, it was Professor Chaston who said in an > EE power course that the law allows utilities to bill only > for real power and not for reactive (imaginary) power. Yep, I'm in the USA. There's a gadget called the Kill-a-watt ( http://www.p3international.com/products/special/P4400/P4400-CE.html , US $25-40) that measures both real and reactive power for whatever's plugged into it. Sounds like it might be fun to play with. Adam
From: Adam on 10 Oct 2007 20:25 Moe Trin wrote: >> Let's see... my latest electric bill (the big one covering July and >> August) comes to about $0.1413 [U.S.] per kW-hr. > > I don't have the sheets handy, but mine is FAR more complicated Mine seems to charge the same, as it's a whole batch of positive and negative five-place decimals, each multiplied by 574 kWh which is what my electric meter showed for, roughly, July and August, when the AC was on a lot. Plus a $15/month "basic service charge" which I never noticed before. >> 15W means about $18.57/year. > > Ah, the simple life. For some people, what they want exceeds what they can afford. I've spent years working on scaling down my wants to what I can afford. > Most printers are meant to be near people, so they do tend to try to > keep the running noise down. I do recall some printers that if you were > going to be close for a while, ear protection was advisable. I found reviews of other laser printers that said something similar. When nothing's printing or scanning, I think the noisiest component is one of the hard drives. >> the printer's rated 10A just by itself. > > Think also what is on that circuit. My house is modern (1990), and the > outlets in each room get a 20 Amp circuit I believe my apartment complex was built in the 1970s -- whether pre- or post-energy crisis (late 1973) I don't know offhand. I found that the outlet my computer system's plugged into is one of seven (seemingly random) electric outlets controlled by a 15A circuit breaker. >> It works with a parallel-port connection. Hasn't yet ever worked >> with 10BaseT connection. > > In one of your earlier posts, you had the card in the computer with > a 192.0.0.192 address. How did that come up? I read somewhere online that the default for HP's JetDirect cards was 192.0.0.192, so I tried setting eth10 to that. Aida32 found 169.254.45.154 / 255.255.0.0 for the Intel Ethernet card, so I tried setting eth10 to that, but 'ping'ing both 169.254.45.154 and 192.0.0.192 got no responses. >>> I'd also like to see them commoned up at the building entry point It was easy to find the grounds for the phone lines and the electric lines. Unfortunately they are about 20 feet apart. > the battery is also part of the line filter, and if it's > missing, the system may not be very reliable. Okay, looks like I'll be giving away one APC Smart-UPS 1500, minus battery, at the next LUG meeting. >>> you should be getting an annual water quality report from the water >>> supplier - it's an EPA requirement. Water bill goes to the conglomerate that owns this place -- rent includes "free heat and hot water." Their web site had a piece on another apartment complex where they saved money by having the tenants pay their own water bills, but that would mean a separate water meter for each apartment. Adam
From: Peter D. on 11 Oct 2007 04:39 on Thursday 11 October 2007 10:25 in the Usenet newsgroup alt.os.linux.mandrake Adam wrote: > Peter D. wrote: [snip] >> It is usually not worth >> the effort in an ordinary home, but adding an extra capacitor or >> inductor to balance out the existing reactive load so that the >> whole thing appears to be resistive can minimise your bill in >> special circumstances. Remember that you would have to re-tune >> the device every time you turned anything on or off. > > Just curious... would it be possible, in theory, to build a gadget that > would plug into a household electric outlet and automatically switch in > inductors or capacitors as needed? The idea being it would > automatically bring the power factor closer to one, for the household or > at least that one circuit, and save some money. Yes, definitely. The better computer power supplies have Automatic Power Factor Correction. Unfortunately if you have to ask questions about this you are not the man to do the job. Mains voltage is *dangerous*. > Robert M. Riches Jr. wrote: >> If Adam is in the US, at least in theory the meter installed >> by the electric utility is _supposed_ to properly measure >> real power and disregard reactive (imaginary) power. If I >> remember correctly, it was Professor Chaston who said in an >> EE power course that the law allows utilities to bill only >> for real power and not for reactive (imaginary) power. > > Yep, I'm in the USA. That is another good reason not to bother. Imaginary power does lead to real power losses in the transmission lines, but that is not your problem. Neither is it something you can reasonably fix. > There's a gadget called the Kill-a-watt > (http://www.p3international.com/products/special/P4400/P4400-CE.html , > US $25-40) that measures both real and reactive power for whatever's > plugged into it. Sounds like it might be fun to play with. > > Adam -- sig goes here... Peter D.
From: Jim Beard on 11 Oct 2007 21:52 > Adam wrote: >> Just curious... would it be possible, in theory, to build a gadget that >> would plug into a household electric outlet and automatically switch in >> inductors or capacitors as needed? The idea being it would >> automatically bring the power factor closer to one, for the household or >> at least that one circuit, and save some money. > Peter D. wrote: > Yes, definitely. The better computer power supplies have Automatic > Power Factor Correction. Unfortunately if you have to ask questions > about this you are not the man to do the job. Mains voltage is > *dangerous*. U.S. household mains is 110V, not 220/240V. It is reasonably safe to do many things around the house in the U.S. that should be done only by a trained technician, where the higher voltages are in effect. Cheers! jim b. -- UNIX is not user-unfriendly; it merely expects users to be computer-friendly.
From: Moe Trin on 11 Oct 2007 22:44
On Thu, 11 Oct 2007, in the Usenet newsgroup alt.os.linux.mandrake, in article <j4ePi.2039$yJ2.925(a)trndny01>, Adam wrote: >Moe Trin wrote: >> I don't have the sheets handy, but mine is FAR more complicated > >Mine seems to charge the same, as it's a whole batch of positive and >negative five-place decimals, each multiplied by 574 kWh which is what >my electric meter showed for, roughly, July and August, when the AC was >on a lot. Plus a $15/month "basic service charge" which I never noticed >before. We have a daily charge (~$.50) a monthly charge (~$0.45), charges for each KW which vary by day/nights+weekends and by season, and taxes and fees. There are 20 separate rates that make up the bill, only two of which are less than five significant digits. But then, my water bill (which includes sewer and solid waste) has a total of eleven billable items broken out... for three products/services. >For some people, what they want exceeds what they can afford. I've >spent years working on scaling down my wants to what I can afford. My sister in Connecticut giggles about my summer electrical bill. I snicker about her winter heating bill. >I found reviews of other laser printers that said something similar. >When nothing's printing or scanning, I think the noisiest component is >one of the hard drives. At work, printers are in small closed rooms to keep the noise down. When the shipping guys are unloading pallets of paper (the printers in each room go through several reams a day so a pallet is about a weeks supply), you could hear the printers a hundred feet away. >I believe my apartment complex was built in the 1970s -- whether pre- >or post-energy crisis (late 1973) I don't know offhand. I found that >the outlet my computer system's plugged into is one of seven >(seemingly random) electric outlets controlled by a 15A circuit breaker. The apartment I lived in before I got married (~400 square foot) had a 15 Amp breaker per room. I had some fun even then trying to juggle the load to avoid popping breakers. >> In one of your earlier posts, you had the card in the computer with >> a 192.0.0.192 address. How did that come up? > >I read somewhere online that the default for HP's JetDirect cards was >192.0.0.192, so I tried setting eth10 to that. Ah, OK - wrong idea. For this, you'd set the eth10 to some other address on the same network - such as 192.0.0.29. Then try to telnet to 192.0.0.192 and see if the printer responds. >Aida32 found 169.254.45.154 / 255.255.0.0 for the Intel Ethernet card, >so I tried setting eth10 to that, but 'ping'ing both 169.254.45.154 and >192.0.0.192 got no responses. That sounds as if your configuration didn't get accepted. If the card has address $FOO, pinging that address will get a response if there is no firewall involved, and the NIC is "UP". It's not actually doing anything with the card (the kernel knows when it's talking to itself and will use the loopback), but depends only on the networking stack being set. The 169.254.x.x addresses are "Link Local" also known as ZeroConf, and _generally_ mean that you've set the interface to DHCP, and the system can't find a DHCP server (so it reaches up it's a$$ and grabs a random IP address out of the 169.254.x.x range). As for ping not working - that may be disabled or blocked. Let's try this: /sbin/ifconfig eth10 down /sbin/ifconfig eth10 192.0.0.29 netmask 255.255.255.0 Does /sbin/route -n show a route to 192.0.0.0? If not, then /sbin/route add -net 192.0.0.0 netmask 255.255.255.0 eth10 and then try ping -c1 192.0.0.192 /sbin/arp -a What this does is kill the existing setup on eth10, bring it up with the local address 192.0.0.29 with a mask of 255.255.255.0. That action should also set a network route, which we check with the route -n command. The 'route add' command would add the network route if it does not exist. Finally, ping what should be the default address of the printer (you should be able to reset it to this by holding the ONLINE or GO buttons down when you power up the printer). I can't remember if it shows the IP address (and anything about the network interface) on the printer "test page". >>>> I'd also like to see them commoned up at the building entry point > >It was easy to find the grounds for the phone lines and the electric >lines. Unfortunately they are about 20 feet apart. It's legal - but it's not "right". The problem you get into is when there is a local (literally) lightning strike. Everybody thinks that "ground" is "ground" but the real ground point is often some number of Ohms further into the ground. When you have a local lightning strike and the current is reaching for that real ground, the resistance between the ground rod and that real ground translates into a (possibly) substantial difference in voltage. But another ground rod some distance away isn't seeing that current flow (even though it may have a similar amount of resistance to that real ground), and the I^2R voltage isn't there - translation: ground rod A is 1000 volts above the real ground while rod B is perhaps only a few volts. If your phone is grounded at A and the power at B, there will be an appreciable difference in those voltages, and this will translate into smoke at the thing that isn't meant to see that kind of voltage difference. The surge protector is (in your case) going to try to handle that difference. >Okay, looks like I'll be giving away one APC Smart-UPS 1500, minus >battery, at the next LUG meeting. I didn't realize the battery is missing. >Water bill goes to the conglomerate that owns this place -- rent >includes "free heat and hot water." Their web site had a piece on >another apartment complex where they saved money by having the tenants >pay their own water bills, but that would mean a separate water meter >for each apartment. Of course - they don't reduce the rent (or at least reduce it the amount they had tacked on to cover the water bill). Yeah, I remember those days - getting the annual note from the owner that expenses and taxes have increased, so we're increasing the rent "but only enough to partially cover the increase in taxes". In the 12 years I was in that apartment, the rent went up 3 1/2 times ($200 -> $700/month). The taxes that had gone up were their income and property tax. As regards the Water Quality Report, see if the water supplier has a web site or give them a call. It _may_ also be on file with the EPA and possibly findable with a search engine. Old guy |