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| Paul_L Guru  Joined: 03/03/2016 Location: United StatesPosts: 769 |
@rob .. they have to eat much of their food raw ... LOL! With AWG 14 wires fed by a 15A breaker we can run a 1550 W heat on 120 v at about 12.9A. AWG 12 wires fed by a 20A breaker will deliver nearly 2200W at 120 v. In my current house the kitchen stove is plugged into a 50 A / 240 v circuit with a 2/5 inch diameter plug with three Y shaped prongs. The stove has 3KW, 2.5KW and 2KW radiant surface burners with a glass top and two 4 KW ovens. Different utility companies in different areas wire the secondaries of the pole transformers feeding residential services in "Y" or "delta". "Y" secondaries deliver 208 v / 120 v / 2 phase to homes, "delta" secondaries have three center tapped secondaries so they deliver 240 v / 120 v single phase to homes. The individual transformer primaries are most commonly 33Kv / 3 phase / 15KW / 220 ma. This google view shows the overhead service going to my house. You can pan and tilt the google view. My house was built in 1976. If you click your way down the road to the west and around the bend you will find newer homes, post 1990, where the utility company has buried the wires going to the houses underground. You will see green metal boxes on the lawns which house transformers. https://www.google.com/maps/@41.6101577,-73.8123759,3a,60y,276.47h,96.16t/data=!3m6!1e1!3m4!1st6Ao5pzDE6SwLVxtoz6JdA!2e0 !7i13312!8i6656 The average service in new homes has a capacity of 150 A / 240 v / 36000 W. In most states with most utility companies you have to notify the utility if you plan to draw more than 15000 W. I don't think there is any location where homes don't have 240 v (or maybe 208 v) available on the pole. You might be able to find some very old homes that still have wiring for 120 v only. I grew up in one of those on a dairy farm. It had a 120 v / 30 A service fed by snap in cartridge fuses. But it was rewired with a new circuit breaker panel and a 240 v / 200 A service back in 1956. We did heat that house with a wood burning furnace and a wood burning kitchen stove. The wood burning furnace is still there but I don't think they use it much. The wood burning kitchen stove was replaced by an electric model in 1956 when the new service went in. I can see burning twigs, but squirrels, rabbits, possums and woodchucks make good stew. Paul in NY |
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| lizby Guru Joined: 17/05/2016 Location: United StatesPosts: 3027 |
It's surely a testament to frontier virtues that we in North America have been able to survive, what with the wet hair and clothes and the tepid beverages. PicoMite, Armmite F4, SensorKits, MMBasic Hardware, Games, etc. on fruitoftheshed |
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BobD Guru Joined: 07/12/2011 Location: AustraliaPosts: 935 |
OMG don't tell me you drink warm beer. |
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| Boppa Guru Joined: 08/11/2016 Location: AustraliaPosts: 814 |
Most older homes in Oz are 240v, single phase 80A max (altho I have seen up to 150A single phase instals for larger houses, it is more common to go to 415v 3 phase instead) Our GPO's are usually single or twin, rated 10A 2400w max per gpo, altho 15A gpo's are not uncommon in garages and for aircon units Two phases are very uncommon, mostly in remote country areas with older houses 415v 3 phase is very common, most new houses are wired with 3 phase connections for aircon etc, for residential its usually 40A per phase, altho you can have heavier wiring installed up to 150A per phase, giving you a total of 3 single 240v phases each at 150A Anything over this would be considered a commercial installation and would often have its own private HV stepdown transformer (many blocks of flats have their own transformer locked away somewhere) Most heaters, toasters, kettles are a range of wattages, my kettle is a 2400w fast boil, we have 3 2400w fan heaters The biggest advantage with our 240v single phase is that the wiring is greatly reduced in size, where a heater or kettle rated at 2400w would only draw 10A in Oz, our merkin friends have to have wires capable of handling 20A to get the same wattage, making for more expensive cabling and plugs in comparison with ours |
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| Boppa Guru Joined: 08/11/2016 Location: AustraliaPosts: 814 |
Only in summer, in winter they just leave it out in the snow ;-) One of my friends from the states was amazed when I told him I have only ever seen snow twice in my life, one as a kid and once in my teens, both times were holidays when we went to the Snowy mountains (Thredbo the first time, Perisher Valley the second)- he lives somewhere that gets snow every winter Bah.... (the time I went to Perisher, skied for the first morning, then sensibly spent the rest of the weekend in front of the fireplace at the bar getting comfortably plastered)  |
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| Paul_L Guru Joined: 03/03/2016 Location: United StatesPosts: 769 |
LOL! Wet hair and clothes encourages fungus infestations. That means mushrooms! Yum, tasty! @BOPPA .. What the heck is a GPO? In Australia it seems that 415v 3 phase predominates. That indicates that the distribution transformer secondaries have 240 v windings with each winding 120° ahead of the previous and then the individual secondaries are wired in series. A true 3 phase 415 v 50 A feed would be capable of providing about 36 KW. 100 A would deliver 72 KW. That seems excessive. Do they really routinely bring all 3 phases into residences? Are a lot of the houses heated with resistive heat in Australia? What is the cost of electric power at the residence? Here in semi rural NY my average cost is about $0.22 per KwH which makes resistive heat impractical. 100 miles west of here in rural Pennsylvania a residential rate would be about $0.13 per KwH and many houses over there use resistive heat exclusively. Pennsylvania gets a lot of cheaper hydro power from the Monongahela, Allegheny, Susquehanna, and Ohio rivers. Paul in NY |
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| BobD Guru Joined: 07/12/2011 Location: AustraliaPosts: 935 |
[quote]Do they really routinely bring all 3 phases into residences? [/quote] No, it's not usual. Mostly just one phase but sometimes two phases. They would be used as 230V. [quote]Are a lot of the houses heated with resistive heat in Australia? [/quote] I've used natural gas for at least 40 years but not all have access to that. [quote] What is the cost of electric power at the residence? [/quote] I'm paying AUD$0.1628 per kWh (US$0.122611) a connection charge of $1.0495 per day (US$0.790404). Just thinking about 3 phase. I had it at the last house for a big 1990s Hitachi aircon system. If I turned down the temps on that I could use it for a whole of house refrigerator, not freezing but very cool. |
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| robert.rozee Guru Joined: 31/12/2012 Location: New ZealandPosts: 2294 |
in new zealand towns and cities, electricity is distributed down the streets as 230v 3-phase star with a light grade neutral running down the street that is bonded to earth at each dwelling. houses are usually connected to a single phase with a 100A feed, alternating amongst the three phases as you go down the street. this means that the neurtal carries minimal current beyond the end of the street. in rural areas 3-phase may be brought into a house and fixed appliances and outlets distributed between the three phases. this is done because the much greater distance between rural dwellings precludes balancing the loads across multiple dwellings. i am not aware of 2-phase being used anywhere. domestic aircon is generally only single phase, as in nz the weather is usually quite mild. in australia (and america i believe) aircon is used for cooling in summer much more than it is here. our electricity costs about nz$0.25 per unit, having risen progressively over the years since deregulation of the market. this has pushed consumers towards heat pumps and better insulation. cheers, rob :-) |
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bigmik Guru Joined: 20/06/2011 Location: AustraliaPosts: 2870 |
OMG don't tell me you drink warm beer. Sacrilege!!  Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<< |
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TassyJim Guru Joined: 07/08/2011 Location: AustraliaPosts: 5923 |
Current charges in Tasmania are about $1.10 per day supply charge for general and heating. General power is 26c unit and Heating and Hot water is 16c unit. I used to run a 6kW 'resistive' heater which heated 2 rooms. 10 years ago I changed to a heat pump/air con which heats/cools the whole house and has a maximum energy consumption of 4.5kW The off grid gurus here will be shocked by my 22 kWh per day consumption. Re the imported power devices. Buying form local suppliers should be safer but not always. We hope the regulators find out about the failures and initiate a recall before anything too disastrous happens. There were recent recalls for bower boards sold by Woolworths and Bunnings. In Grogster's case, if he is the importer, he is the one held responsible when something goes wrong. Like Grogster, I wouldn't like that hanging over my head. Jim VK7JH MMedit  MMBasic Help |
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| bigmik Guru Joined: 20/06/2011 Location: AustraliaPosts: 2870 |
Lads, Well we have to keep our beer COLD!! 16c per kilofirkin... we are paying about 38c peak and 19c off peak but they pay me 68c for every kW my solar puts into the grid. Kind Regards, Mick Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<< |
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| bigmik Guru Joined: 20/06/2011 Location: AustraliaPosts: 2870 |
All, I am truly amazed at the different electricity prices in Aus.. As to usage, before we went solar in 2010 our daily average was 32kW per day.. considering we froze our dangly bits off in winter and roasted ourselves like pork crackle in the summer and changed all bulbs to LED/CFL I find it hard to believe we use so much.. I had everything tested by a sparky and he found nothing wrong.. Since the solar went in our daily use has dropped considerably but I cant tell how much really as we draw off the solar before pulling from the grid. We may have had a faulty meter.. Now with the 5kw solar and premium feed in tarrif I dont care much as we about break even $$$ wise. @Paul_L.. A GPO is a General Power Outlet wall power point.. I have only heard the term in my work, we never use it in the home.. we call them power points. Kind Regards, Mick Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<< |
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| BobD Guru Joined: 07/12/2011 Location: AustraliaPosts: 935 |
Mick What is a kilofirkin? Is it a new type of electrickery? I just checked and in our highest electricity consumption month of August 2016 we used an average of 11.5 kilofirkins per day. However, our hot water, heating, and cooking is gas. The gas bill gets a bit savage in the winter. Our electricity charge is apparently 35% down on the government approved standing offer. Our daily charge is discounted by 5%. It's a flat charge with no off peak usage charges (the gas does that). Bob |
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| Boppa Guru Joined: 08/11/2016 Location: AustraliaPosts: 814 |
Sorry, yeah the general public uses powerpoints, I am an elec fitter by training and got in the habit of calling them GPO's, plus its a lot quicker to type gpo, than powerpoint... A lot of the new houses are actually installing 3 phase as standard for aircons etc, but the standard for most of Oz is still single phase 240v Ive rarely seen 2 phases installed at all, its single or 3 phase - some people might get confused into thinking they only have 2 phases as some installations (S.A. I believe had them) only had 2 meters to monitor 3 phases consumption Oz almost always in home systems use the 3 phase with neutral (star wired), this can then be split into 3 single phase 240vac supplies for load spreading |
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| bigmik Guru Joined: 20/06/2011 Location: AustraliaPosts: 2870 |
All, @BOB, It was one of my silly jokes.. A --- > FIRKIN <--- is a measure of beer volume, equivalent a a quarter of a barrel.. I just checked our bills and my current charges are about 36.4c peak and 16.4c off peak (slightly different from what I quoted) and $1.11 per day Usage on top of what we drew off from our solar last 3 bills of last year were 22kw/day 13.5kw/day and 25.5kw/day so that sort of suggests we are still around 32kw/day usage. when we opted for solar the average of our last years (was 2009 total of 4 bills) bills was $720per quarter or nearly $3000 per year.. We also use gas for cooking and whilst we have ducted heating (Gas) we almost always use reverse cycle aircon for heat. Must be all those micromites I have on `burn-in'  Kind Regards, Mick Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<< |
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| TassyJim Guru Joined: 07/08/2011 Location: AustraliaPosts: 5923 |
A lot of rural consumers are on single phase (two wires) HV and even SWER lines. SWER - Single Wire Earth Return. The high cost of running more HV wires than really needed is prohibitive when you are talking many kilometers. When they want something more potent than 240V single phase, they can get two phases, 180 degrees apart to give 480V. Very handy for large welders etc. Jim VK7JH MMedit  MMBasic Help |
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| Paul_L Guru Joined: 03/03/2016 Location: United StatesPosts: 769 |
Clarification ... when I say two phase I mean two phases 120° apart. Two phases 180° apart are not different phases, they are the reverse polarity of a single phase and probably come from a center tapped secondary. I suppose they could also come from the fact that you are in the southern hemisphere and the coriolis effect causes your hurricanes to spin the other way. Believe that and I'll dream up another one. Do your toilets really spin the other way when you flush them, or do they stand perfectly still like ours do? What voltage range is normally used on the primary side of the last step down transformer in residential areas? Paul in NY |
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| TassyJim Guru Joined: 07/08/2011 Location: AustraliaPosts: 5923 |
Flush toilets - now that's getting a bit too posh for us. Re the supply voltages. The tap range available on distribution transformers tends to vary. We also have a lot of different HF distribution voltages to contend with. To quote from a 2011 supply standards document: Typically, the linesman would set the no load voltage close to 250V although with solar feed-ins, that will need to go lower to stop high voltage cutouts all the time. Didn't have solar to contend with in my days. Jim VK7JH MMedit  MMBasic Help |
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| Boppa Guru Joined: 08/11/2016 Location: AustraliaPosts: 814 |
SWER is still fairly common in rural Qld, but I'd never seen a 480v 2 phase 180 deg one before- apparently they did (still do?) exist, most references seem to be in Tas or Vic tho learned something new today  |
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Grogster Admin Group  Joined: 31/12/2012 Location: New ZealandPosts: 9083 |
Love the international power conversation going on here guys, keep it up. [Quote=TassyJim]In Grogster's case, if he is the importer, he is the one held responsible when something goes wrong. Like Grogster, I wouldn't like that hanging over my head.[/Quote] Yes, in my case, as I am the importer, the buck stops with me for compliance. In other words, it is up to ME to ensure that anything that plugs into the mains, is compliant with any electrical safety regulations. Technically, this would mean submitting a sample of the plug-pack to an accredited lab for testing - all very expensive. Far easier to just bin the one that comes with it, and use one from Jaycar, which IS already tested as safe by Jaycar before they sell it. For retail(Jaycar Electronics shops), before they can sell anything that connects to the mains to the public, it must have passed compliance. So much safer from an actionable position, to use plug-packs supplied by them, rather then bother trying to certify ones myself - not that those ones would have passed anyway!  "GPO" - General Purpose Outlet, was what I always thought it stood for. The geeks way of describing the standard wall socket. We had a major pole replacement here last week, and power was not back on before it was dark, and many in the street were intrigued by the fact that SOME people got juice back before others. This is all because of the three-phase supply at the street poles and the load-spreading that Rob talked about. The houses are staggered across the three phase supply, so as they connected the first, second, and then third phase, a few houses had lights, but most not, then a few more, then the rest. Most people in the street who were talking to me about this, were totally unaware that the street supply was three phase. But then - why would they unless they had an interest. So long as THEY have juice.....  Smoke makes things work. When the smoke gets out, it stops! |
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