I’m back home. Thanks to everyone who helped while I was offline with family medical issues. There are larger challenges ahead but for now things are back to near normal. Thanks to everyone who left kind words in the announcements thread – I feel like Jimmy Stewart at the end of “It’s a Wonderful Life”.
One thing I always like to do on trips south is to visit Fry’s electronics. There, I can take in the full measure of what’s new in the electronics world. While there, I picked up a gadget that solves an ongoing problem in my home. This is worth a read if you want to save money on your power bill.
While some of my incendiary foes like Joe Romm would like to make you believe that I’m anti-everything (his favorite word is “anti-science” when describing anyone who doesn’t agree with him), those of you who read WUWT know that I’m proactively energy efficient. For example, earlier this year I wrote about installing super efficient LED recessed lighting in my home. I’ve yet to see Joe Romm write a single positive thing about what he is doing personally to practice what he preaches.
I recently went through a home energy audit related to my recent Smartmeter installation (which is another story all by itself) and one of the things I decided I needed to do something about was the growing number of vampire power suckers in my home. As we added more technology, the number of always on power sucking wall-warts (120vAC to 12Vdc power transformers) increased.
Until now, there wasn’t any really practical way of dealing with them all, so I thought I’d share this solution since I’m sure many of you have similar problems with vampire power.
First some background. Here’s a video on vampire power from iGo:
Defining the problem:
Lawrence Berkeley National Laboratory has a whole website dedicated to standby power issues and offers this assessment:
An individual product draws relatively little standby power (see here for examples) but a typical American home has forty products constantly drawing power. Together these amount to almost 10% of residential electricity use.
That 10% for me is an issue, because on hot summer days when we need a/c the most, that standby power baseline adds to our allowed PG&E baseline use, and when we go over it, our electricity costs escalate rapidly. PG&E actually punishes residences who consume over the allowed 445 kwh baseline in tiers, such that by the time you exceed 200% of baseline, your cost per kwh is now at 40 cents per kWh, which is outrageous.
Unfortunately, PG&E is a monopoly, and the Public Utilities Commission in California actually approved this outrageous rate hike for over baseline use while simultaneously dropping the allowed residential baseline from 512 kWh/month to 445 kWh/month in the last year. It was a major blunder, and this is why Smartmeters have been getting such a bad rap. PG&E chose the worst possible time to start, in May. Combine new rates, smartmeter swaps, and summer temperatures and you get a PR disaster and people up in arms.
Here in the Sacramento valley, we have temperatures here that reach 110 degrees at times, requiring a/c use. My only option now with these new rates is to reduce energy use. Now that’s something I don’t mind doing, I’ve been proactive at it, but I must say I feel discriminated against compared to Californians who live on the more temperature coast, because I already live in an energy star rated newer (4 years) home. They don’t have a/c issues like we do in the central valley.
So in a nutshell, I’m hosed by my location and its summer climate. That’s why my July 2010 energy bill was $620.16 (electric, plus gas, plus loads of taxes and other taxes – like “public purpose programs”, part of which supports climate change research in California) last month for 2052 kWh of use. If it were at regular baseline rate the bill would be half that. So anything I can do to get closer to baseline will be helpful.
Measuring the problem:
I went around my home with an LCD meter called the Kill-a-Watt EZ and determined that I have 3 areas of significant vampire power use that could benefit from a makeover.
These can be ordered from Amazon for about $30 plus shipping and are dirt simple to use. They can show you instantly how much standby power is being drawn on any appliance or power strip. There’s also a graphing version and a power strip version.
While I had all sorts of spots all over the house, I identified three areas where phantom power was concentrated and working to kill the vampires would be a worthwhile effort.
- My computer workstation where I manage WUWT and research
- My wife’s computer workstation with central printer
- Our entertainment center and TV (#1 draw)
All of these had a collection of wall-warts for network switches, speakers, USB hubs, amplifiers, and accessories. The main devices like the TV, DVD player, DVD reorder, satellite box, all had “instant on” features and drew a fair amount of load and most of these were on 24/7. Just looking at them in infrared shows where that power was going:
So not only are they wasting electricity, they are dumping waste heat into the house 24/7, adding load to the air conditioning.
According to this interactive page at Lawrence Berkeley National Laboratory, I had all the vampire family members. My own readings from the Kill-a-Watt meter were right in line with these:
What was the biggest surprise to me was how much standby power my set-top satellite receiver boxes were drawing. I have a newer model and older model from DirecTV. The older model was drawing 31 watts in standby! Again right in line with what LBL says:
You can see the LBL master list of appliance tests for standby power draw here.
Finding a solution:
One way to solve phantom power draw is with power strips. I already use these to corral wall-warts, and when we go on trips I make it a point to reach behind the computer, under the desk, and behind the TV to shut these off.
However, doing that every night is a bit of a pain, and often forgotten in my house. So, the little suckers live through the night and during the day when we aren’t home.
So while a switched power strip *does* solve the problem in principle, it doesn’t in practice due to access. The strips are all behind and/or below something.
I had been toying with the idea of making some sort of remote switch for my power strips so I could easily turn them off when I shut down my PC, or turn off the TV and go to bed. Fortunately, I found a solution at Fry’s yesterday that did just that.
A way cool plug-in gadget that kills power vampires:
I was really happy to find this power strip gadget at Fry’s:
Apparently this was introduced at CES in 2008, but this is the first time I’ve seen it. It pays to advertise I suppose.
In case it isn’t obvious, this is a power strip with a wireless remote switch. The switch can be handled like a TV remote or wall mounted, making it easy to remember to kill the vampire when you turn out the lights to leave the room.
The remote has a range of 60 feet and can be set for 8 different channels so you can have multiple outlet strips in the home. Here’s some features:
Here’s the manual (PDF)
Installation was quick and easy for me, I just daisy chained from my existing power strip and chose which devices to plug in to “always on” and which to put into the “switched” outlets. See below:
Of course I had to make two wall-wart exceptions: answering machine and my home weather station (which has a data logger and automatically updates a web page). Now that I have it working and can easily kill off most of my office vampires, I’m planning on buying two more for the other locations that have heavy wall wart populations.
I highly recommend this product. Amazon.com has the best deal on the base model at $34.99 and there are other models which you can see here. There are also UK/European and Australian power outlet versions I’ve found.
While we might disagree on climate change, saving money by reducing energy use is something I think we can all agree on.
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jorgekafkazar says:
September 5, 2010 at 10:48 pm
Jeff Alberts says: Here’s some features:
“In English that would be “Here are some features:” ;)”
In American, that would be “Here’s some of it’s features.”
In Canadian, that would be “not all features on all models, and models with features are special order. Some features available at extra cost, eh?”
Ooooooh – now we’re in Lister, or, more appropriately Listeroid territory!
What is a Listeroid? A diesel engine that could easily outlive you as applied in daily generator service …
http://www.google.com/search?client=opera&rls=en&q=listeroid&sourceid=opera&ie=utf-8&oe=utf-8
Basically, these are low-shaft-speed, high torque, large-flywheel mass prime movers that when coupled with a properly engineered generator head are able to start induction-motor loads that often requires a ‘hardware-store’ generator of 2 or 3 times the KW capacity … i.e., a 3 KW based Listeroid power source will rival your light-weight Chinese-made 6 KW genset insofar as starting capability on account of the large flywheel mass coupled to the generator head (whose ratings allow a 2x capability for motor starting) AND YET it will have the fuel-efficiency desired in a continuously-run genset …
Full disclose: – I have no pecuniary involvement with Lister, Liseroids or accessories.
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Here’s a hidden “power vampire” you likely haven’t heard about: your thermostat system(s).
Your wall-mounted thermostat most likely is low-voltage. (There are some line voltage thermostats, used for electric baseboard heat and in-wall mounted heaters without their own thermostats.) So down at your furnace, for example, there is a power supply, likely an iron and copper transformer, supplying that voltage to your thermostat, waiting for it to switch on when it will also power a relay that turns the heating on.
Do you have separate central heating and cooling systems? Each has its own power supply. Have you “zoned” your heating, perhaps while trying to save money, letting you set different temperatures for different areas? For two zones, you likely have three supplies, one for each thermostat plus the controller back at the furnace, possibly more. Also, a furnace that maintains a standby temperature, like for a hot water (hydronic) system, also uses power just monitoring that temperature.
Is winter approaching and you are done using your central air conditioning? Turn off the breaker. Summer approaching, done with using the central heating, turn off that breaker.
BTW, do you have mixers on your water lines? Those are the “anti-scalding” devices that mix cold water into your hot water to keep you (the idiotic water-user) from accidentally using too much heat, aka automatic mixing valves, likely set around 120°F. These days they may be required where you live. If your furnace is your water heater (“domestic hot water coil” built into your hydronic furnace) there normally is only one thermostat controlling the furnace, set to the temperature of the water circulated for heat, thus you may have a whole-house mixer. Mixers may be point-of-use ones such as for your shower, added to the plumbing or even part of the valve(s) as with some shower faucets.
Thus you may be paying to heat water hotter than you are actually using it. With a domestic hot water coil, check the setting of your furnace for non-house-heating months and set it to what you need for just water heating, which is good to do with or without mixers. If you have mixers, consider if you really need hotter water at certain locations, like the kitchen sink, and if not then set the water temperature below the mixer setting.
In concept, I like the idea of plumbing a house with only cold-water lines until you get to an “area of use” like the kitchen or a bathroom, and at one you use a tank-less “instantaneous” water heater. Too bad the buggers cost so much, and non-electric ones have additional hookups needed like fuel lines and exhaust venting, thus possibly negating any savings over the expected life of the units versus traditional central water heating.
A gadget like that with a timer on it would be even better. Plug your cell phone into the strip, push the on button, and it turns off ofter a preset time.
Does your A/C route the evaporator condensate back to the outside condenser for additional cooling? I saw somewhere that this can improve A/C efficiency by up to 10%.
I didn’t want to punch a hole in my garage brick (no windows) for an air conditioner and modified a 13,500 BTU window unit with a condenser jacket for water cooling with the water dumped outside through a garden hose hole in the brick. The unit has a delta of 26-28 deg F with less than 1GPM usage. Of course it helps that I am on a well with a water softener and don’t have separate water utility rates.
Unfortunately it is really difficult to get overall large efficiency improvements without major changes in the house (extra insulation, better windows, good attic ventilation, etc.) which can be expensive if contracted.
Probably the best way to dramatically improve this kind of situation is to move to an area where the cost of living, including electric/gas rates is way less.
And Doc you may want to consider moving to here, where there is NO personal income tax and here is what our electric bill for the last 12 months:
Sep 3335kWh $411.54
Oct 2678 329.81
Nov 3133 386.40
Dec 2168 266.34
Jan 4248 516.89
Feb 4151 505.00
Mar 3869 470.46
Apr 3567 433.50
May 3147 382.04
Jun 4066 494.61
Jul 3524 428.22
Aug 4282 521.06
That’s TOTAL, including taxes.
Of course, it is a 4,000+ Sq. Ft (not counting the garage & under-the-roof lanai) all electric (except for the two LP instant hot water heaters and 6 burner BBQ) house with 18,000 Gal in-ground heated pool and separate 330 Gal SPA. You can no doubt pick out the spring/fall like months out of the list because even though the house is insulated to the nth degree and I designed it to take max advantage of the natural ground temp of 70 degrees here in C. FL, we still need the A/C when it’s hot like right now, 91, or cold when the fronts come through in the winter, you know like 30 degrees…. or when we’re not here for a couple of weeks as we do turn all but essentials off and I am going to get a couple of those remote units to make it easier.
Mods, if I may, a couple of related, but as of yet unmentioned items that I think are important to any discussion involving the topic at hand (household AC Mains power and safety, efficiency, including power distribution efficiency) –
1) Arc flash circuit breakers – protective devices that act as more than just fuses in protecting personnel and equipment from hazards involving the “AC Mains”:
“Arc flash – Electrical fires in homes … more than 40,000 times each year … U.S. alone. A significant portion of these fires result from unintended electrical arcs in a circuit that standard circuit breakers are unable to detect. Arc-fault circuit interrupter (AFCI) detects arcing faults and opens the circuit to stop the flow of electricity.”
http://www.arcadvisor.com/afci.html
http://www.google.com/search?hl=en&client=opera&hs=Vo2&rls=en&q=arc+flash+circuit+breakers&aq=f&aqi=g1&aql=&oq=&gs_rfai=
2) Power factor correction as it applies to power supplies (PSUs) – which are a different kettle of fish than simple VARs (Volt-Amps Reactive) as applied to inductive (motor) loads:
PFC – A Little Old-School Knowledge – Part I – http://electronicdesign.com/article/power/pfc_a_little_old_school_knowledge.aspx
APP NOTE – UNDERSTANDING POWER FACTOR – http://www.thierry-lequeu.fr/data/AN824.pdf
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Forgot to mention that putting an extra layer of duct facing on the “outside” of metal ducting and double wrapping attic ducting would also help as I’ve seen 2-4 degree temp increases from the evaporator to the longer duct outlets and gaining most of this back would normally amount to to 10-15% efficiency gain for a 18-20 deg delta unit. This is also a relatively inexpensive fix.
The answer, Anthony, is that by saving money by removing unnecessary energy use you are simply increasing Joe Romm’s energy use by causing him to go into yet more infantile rages about your attitude to climate change.
Nobody wins in those sorts of situations.
I think the solution is actually simpler. Now that you’ve installed a smart meter just wait for PG&E to turn off everything for you 🙂
You guys are nibbling around the edges. This thread has been like watching Obama recommend that a good way of increasing your fuel economy is to check your tire pressure.
I have been amazed to read this entire thread and to see that only Steamboat Jack, who suggested voting with your feet, and Mr Black, who wrote,
“We should be raising hell against this kind of government mandated impoverishment of ordinary people, not accepting it as our duty to the planet or whatever other moral fiction the AGW crowd would create for the little people to live by. I want to save money as much as the next man on my power bill but NOT because the government has made it too expensive to live a comfortable life.” even hinted at the real problem.
The real problem is renewable-power mandates.
The greenies love them, because they get built into the power bill, so everyone has to pay. Electric utilities love them because their cost is embedded in the rate base, so that a markup is incorporated into the tariff used to calculate consumers’ power bills.
The ‘renewable power’ lobby loves them, because they disguise the true cost of ‘green power.’
I hate them, because they ruin once-pristine windy vistas, and kill thousands of birds in the process, doing so at obscenely high cost.
Every wind generator and every solar generating facility increases your power bill because of the purchase mandates that require utilities to purchase the power at the inflated rates necessary to make the wind and solar facilities profitable, not to mention the tax preferences and other subsidies involved in their construction.
I pay Puget Sound Energy $.085544 per kwh, plus and minus nickels and dimes, for my power. Puget’s production costs, for other than renewables, haven’t increased very much since the time when I paid them about $.06 per kwh. the difference is renewable mandates, plus a little inflation.
If you continue to vote for politicians who are cheerleaders and advocates for renewable power, your bills are going to increase, and you will be responsible for that increase, which occurs as a result of your actions.
No amount of tinkering with incidental loads in your house is going to make a tinker’s damn worth of difference.
It’s going to get worse. The renewable guys are promoting the idea of “feed-through tariffs”, a scheme used to promote investments in solar and wind power by individuals, in which you will have not a smart meter, but two meters. One meter will measure the power used by you, and the other will measure power generated by you, for which you will be paid an exhorbitant, mandated price.
The way this is sold is to argue that peaking power is sold at the spot price, which is very high, so that the market will turn to renewable sources, which generate power for a subsidized, but less than spot price. In this way, adherents are able to argue that the use of renewable actually lower the cost of electrical power for everyone.
Their claim is based on the false premise of the very high true cost of peaking (Usually natural gas fired turbine) electrical power.
If you don’t start to vote against politicians who will shaft you with renewable mandates, you have only yourself to blame. I’d suggest that you hold your inflated power bill up next your face as you look in the mirror, while you say, “It’s your fault, dummy.”
If any site on the web is more rational than this about climate issues, I have yet to find it. I’m surprised that commenters here have not been more aware of the true cost of climatological and environmental claptrap, and more aware of the cost of government intervention in what should be free markets.
D. O. says “The real problem is renewable-power mandates.”
It’s worse than you know. CA mandates buying renewable peak power, which comes from British Columbia. BC says it’s Hydro power, but no one can say what it is, once it’s in the grid.
It may even be conventional power bought from Washington. Thus, our bureaucrats let them launder power that’s illegal for us to buy directly.
Bring on the tar, feathers and pitchforks.
I’m on the board of a condominium association that has mandated exterior lighting, the use of which is intended to illuminate house numbers at night, mostly for the use of visitors and emergency responders. We originally specified 50PAR30 lamps for the purpose in the installed downlights that illuminate house numbers, but we have have subsequently replaced those, as they fail, with 11-watt, Edison-base CF lamps. Since the lamps are on all night, the energy saving is considerable. I would argue that this is a reasonable use of energy-saving techniques.
Some of you people are scaring the heck out of me.
The HIGHEST electric bill I have had in the last 12 months is $165.42 USD.
That was for July and I am air conditioning 3750 sqft.
In your haste to excoriate the bulk of us did you overlook this fine post by Gail which begins: “Governments are the biggest block to innovation.“?
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Anthony, and others contemplating reducing electric bills due to California’s tiered rates system.
You could consider converting the home to a time-of-use plan for electric service, then installing a cooling system that runs at night on off-peak power, produces and stores chilled water, then runs only a small pump and a circulation fan during the day. link to Southern California Edison’s TOU plans:
http://www.sce.com/CustomerService/rates/residential/special-time-of-use.htm
PG&E’s offering: see E-6, E-7, and E-9 at http://www.pge.com/tariffs/ERS.SHTML
Note that E-9 is a Residential Time-of-Use Service for Low Emission Vehicle Customers, for which an electric vehicle may qualify.
There are several commercially available water chilling systems for residential use; an internet search for the keywords “residential water chilling system” should turn up several.
These systems are much like conventional air conditioners, but instead of producing cold air they produce chilled water. The chilled water is stored in dedicated insulated tanks. When home A/C is required, a small water circulation pump sends chilled water through a heat exchanger, the home’s air circulation fan starts, and cold air is blown through the house. This does not completely eliminate electrical usage during the day, or on-peak hours, but it reduces the electric load considerably. As an aside, USC (University of Southern California) installed an industrial-scale system to do exactly this, with the storage tank located under an athletics field. It was huge. These things work.
Another pretty good idea is to add more insulation to attics, and roof vents. I have never trusted any government agency to decide what is best for me and my home, including their Energy Star ratings.
I also cut my home’s energy use, especially air conditioning, by installing trellises on the southern and western exterior walls, then planting a climbing vine. I used Morning Glory vines, because they grow quickly, plus produce a dense foliage and pretty flowers. The trellises were about a foot away from the wall. The impact on the A/C and electric bill was dramatic. The vines can be removed easily when the weather becomes cooler, and it is advantageous to have sunshine beating on the walls.
If there are any windows exposed to afternoon sun, consider installing awnings, or special reflective screens.
Going through the attic with a large roll of duct tape is also good, with the goal of taping every joint in the air ducting system. It is amazing how many air leaks exist in those systems. Checking that there are no leaks where the air duct enters each room also is a good idea. Sometimes builders cut corners, and the cold air reaches the room but part of it leaks back into the attic. This is based, of course, on a central A/C cooling system with an attic-mounted evaporator/fan system with air distribution ducts also in the attic.
Eliminating air leaks to the outside also reduces the A/C load. There are many products on the market to seal small crevices.
Finally, and I’ll stop here, one should keep the air filters to the air circulation fan as clean as possible. These should be checked at least once each month, and replaced with new filters if of the disposable type, and cleaned and re-installed if of the re-useable type.
Coming from the UK I love the unswitched outlets, in England one of my family would switch off AND unplug the bloody thing (kettle etc) given that the UK outlets were double pole switches this was plain foolishness, iritating when you plug in the kettle, switch it on and it never boils????, what about the microwave? I was pleased to read the LED light bit, CFLs are a crock, I cannot find the study that actually measured the average real world consumption of incadesent, cfl and quartz halogen/dimmer, the last being the cheapest in both consumption and longevity/initial cost.
My apologies to Gail, the only other exception to the navel-gazing here about the real costs of power. I continue to excoriate the rest of you.
I’m amazed that micro-nuclear hasn’t received more attention. Given that Toshiba, a giant corporation, is one of the players, I might ask why they haven’t lobbied and marketed more effectively.
Chris Edwards,
” I was pleased to read the LED light bit, CFLs are a crock, I cannot find the study that actually measured the average real world consumption of incadesent, cfl and quartz halogen/dimmer, the last being the cheapest in both consumption and longevity/initial cost.”
In my association, we decided that CFL, Edison base lamps were the best for lamps that would be illuminated all night.
In my own home, I use mostly halogen lamps dimmed by fade-on, fade-off dimmers that I purchased at considerable cost. Replacing those with CFL lamps, not controllable by the dimmers I have installed, would be unacceptable. I don’t like the quality of light supplied by CF lamps.
Eric Anderson,
“2052 kWh of use in July? Holy cow, my electric use isn’t anywhere near that. I know you mentioned heavy A/C usage, but I’m guessing the real culprit is your 12-person jacuzzi and the home tanning bed! Don’t worry, your secret is safe with us. ”
My usage in August, with no A/C, was 360 kwh. I live in 1445 square feet, and our mild climate doesn’t require A/C. I leave one computer on all the time, because I have VOIP, which allows me to avoid $35 per month charges for home telephone service from the regulated utility. Life is about tradeoffs, rather than solutions, isn’t it?
Jim (Sep 6, 12:20 pm)
Thanks for the followup comments. I could (unfortunately?) write about 600 pages on the various diesel options, their pros and cons. I read “too much” and then “think too much”.
The starting load, especially for inductive loads starting pumps (as in A/C compressors) is always a difficult problem. It’s one of the first electrical engineering things that mechanical engineers were (are?) taught. A large flywheel (turning at perhaps several times crank speed) on the generator helps.
Modern power electronics provide more options for dealing with the starting loads. e.g. Brushless DC generation and solid-state A/C synthesis, drawing surge currents from the engine’s starter battery. Not as cheap and simple as a flywheel, but much lighter and more compact.
My example illustrated that the electricity provider must be completely clueless and expect their customers to be even more ignorant and helpless; if they expect the customer to pay the company at a rate higher than than what the customer can easily produce by themselves.
A combined heat-and-power system, with perhaps a direct-drive a/c compressor is a bigger investment, but the cost of “electricity” to “DIY” is then potentially less than the 29 cents a kWh being charged for the amounts in the second step above “base”.
If the customer also has an off-grid PV solar system with their own storage batteries, then that can be integrated as well, utilising the batteries to supply all electrical power at periods of low demand and using the generator to charge the batteries when there isn’t enough sun. That increases overall generator efficiency as it spends less time running with very low loads. Engine efficiency tends to be poor when the load is below about 20% of maximum rated.
I’m curious about how many of you who are investing thousands to save nickels have smart phones with data plans that obligate you to spend a hundred or so a month for fancy communications.
It’s all about choices, again.
I read Anthony’s post about how much money he spent to replace incandescant can lights with LED trims, and I had to laugh at his waste of money. I saw no consideration of an alaysis of the reduction in operating cost in return for his investment, especially considering that the new trims were installed in place of incandescant sources that would be little used in the summer.
It’s nice to be an early adopter, if that gives you pleasure, but most of the “energy savings” claims are laughable.
I used LED sources for undercabinet lighting in a recent kitchen remodel, both because they were cheap and easy to install, but because they will almost free to operate, and are physically inconsequential. They’re tiny and easy to conceal. Mostly, they were very, very, inexpensive. I used a transformer (from a discarded inkjet printer) I had lying around to power them.
Jim —
I’m showing my age, I suppose. When I first started getting into computers and electronics back in the late Sixties (!), electronic equipment normally came in “relay racks” two feet wide by two and a half deep by anything up to seven feet tall, cooled by small fans more or less identical to the condenser fan in a fridge, i.e. 5-15W shaded pole motors. Later, commercially available one-piece “muffin” fans became popular, but they were still 110V shaded-pole motors. Those were used up until about the mid-eighties, when DC fans began encroaching on their territory, but big racks of electronics still sometimes have “fan trays” made with those things. I don’t know of any desktop PC that used AC fans after about the TRS-80 era; the IBM-descended and Apple PCs used brush-motor DC fans until brushless DC fans started getting cheap sometime around 1990 or so.
No, brushless DC motors don’t work on the shaded-pole principle. As I said, they use electronics to create polyphase AC and run on that. The Hall sensors you describe are used for timing; they drive the pass transistors that control the current to each motor phase. Because they change phase based on rotor position rather than frequency, their speed can be varied by varying the current to them, either by changing the voltage or PWM techniques — I’ve used both — just like a brush motor. That doesn’t change the fact that the magnetic circuit inside the motor is polyphase (though not induction, like the motors most people think of as “AC”).
Regards,
Ric
It’s the AMPS that will hurt you, not the voltage. Circuit breakers will trip on excessive amps. If you want to protect against shocks, install ONE GFCI receptacle at the beginning of each circuit and it will protect all the receptacles on that circuit.
As to 120V vs 240V, I don’t know that one is really safer than the other. 240V devices require half as many AMPS as 120V, but these devices usually require a lot more power thus upping the AMPS anyways. But for the same wattage, a 240V circuit is safer as it will require half as many AMPS. This also means that your wires will handle more devices and more wattage.
One thing I did find is that common grounds are sometimes used to service two circuits on different phases. If only one circuit is in use, then you’ll get the normal 120V potential on the neutral wire. But if both circuits are in use with the same wattage, then you’ll have 0V on the neutral. So more using more devices can actually be safer with this arrangement.
In any case, fewer amps means safer environment.
BTW, how many devices are you using on the same circuit? Do you have a 20A or 15A circuit? Overloaded circuits will draw a LOT more power too. You may want to check the AMPs you’re drawing on a single circuit and maybe install another circuit or try to put some devices on a different existing circuit. Something many people don’t know is that breakers will rarely trip on overloaded circuits. You can go over the rated AMPS on a circuit breaker with relative ease. They usually flip with sudden changes. But just plugging in a lot of crap will cause gradual use and won’t flip your circuit breaker causing your wires to expend way more power than needed, above and beyond the draw from the devices connected to it.
Harry Bergeron ,
You’re correct. The operator is free to cook the numbers and shaft you for power they purchase from elsewhere.
The answer is to create a free market for power. The experience with Enron has interefered with this concept, but one should remember that, when Enron was in business, power was still regulated in California, and the actions of regulators in California exacerbated the problem.