Interesting concept
Browse Forums Heating, Cooling & Insulation Re: 3 Phase or 240V 22Feb 03, 2014 8:42 pm We have having 3 phase power with the intention to share the load across all three phases. We have a 5 head multi head split system, a 6 point ducted reverse cycle air conditioner and we will eventually be getting a spa. That's on top of the usual lights, power points etc. Another advantage is more often than not, when you lose power it's often to one phase only. This means that you can still run the items conne ted to the other phases. Example - we recently had the power go out at my parents house (who are on 3 phase) and they were still able to run the air conditioner in the lounge as that was connected to the phase that didn't black out. Custom downslope build Build thread viewtopic.php?f=31&t=61873 Blog http://www.buildingroyalmanor.blogspot.com.au Re: 3 Phase or 240V 24Feb 03, 2014 10:01 pm If you have to run any type of machinery - even a home workshop or a large aircon unit, three phase is the way to go. Single phase motors are only something like 70% energy efficient whereas three phase is around 90%. Stewie Re: 3 Phase or 240V 26Feb 04, 2014 8:25 am Many who get 3 phase on their homes is because they have large ducted a/c that requires an awful lot of power to run. A few get 3 phase because they have a home workshop that has 3 phase appliances in there. Most single phase homes the maximum that can be drawn down that single phase cable is either 63 or 80 Amps. Work out what that ducted a/c system is rated at, and you'll soon see that it takes a huge chunk of that up to 80A that single phase can supply, particulary surge loads at startup and the like, so generally you'll find that such systems are put on their own phase. You could simply think of 3 phase as three single phases combined, so you'll get that up to 80A per phase. So what generally happens is those who get ducted a/c installed, get 3 phase power on by 'default' so to speak. Very few people get 3 phase on primarily for a home workshop. Owner Building at Jimboomba Woods in Logan City Qld. Blog : http://bandlnewhomebuild.blogspot.com H1 thread : viewtopic.php?f=38&t=68283 . Re: 3 Phase or 240V 27Feb 04, 2014 8:32 am Stewie D If you have to run any type of machinery - even a home workshop or a large aircon unit, three phase is the way to go. Single phase motors are only something like 70% energy efficient whereas three phase is around 90%. You're half right there. I'd alter your first bit by saying "if you have to run heavy duty machinery", as most people can run up to around a 280 Amp welder on a single phase house. Considering most people with a welder at home (not talking about professional welding people who work from home), only have up to a 150 Amp welder, that'd be a huge welder. Not disputing the rest of what you say though. Getting 3 phase power on for the 'fun of it', is a waste of time and money. If you have a need, i.e. large ducted a/c, then it only makes sense. Owner Building at Jimboomba Woods in Logan City Qld. Blog : http://bandlnewhomebuild.blogspot.com H1 thread : viewtopic.php?f=38&t=68283 . Re: 3 Phase or 240V 28Feb 04, 2014 8:36 am Very interesting....I'm going to talk with my builder then. If they already have an allowance to run single phase to the meter box, then I would think the extra cost to run 3 phase is cable cost and maybe breakers etc....shouldn't be a huge disparity in install price. Re: 3 Phase or 240V 29Feb 04, 2014 8:46 am Crazyk , if you're getting a large ducted a/c on, then I think you're committed to getting 3 phase on. If you are getting it on because you think it is a 'good idea', then I suggest you have another think. Copper isn't cheap these days, and if the house build is done by a big builder, then chances are that they charge a lot more. 3 phase is four strands of copper (or aluminium), where single phase is 2 strands of copper/aluminium. The earth on both is the copper stake at your meter box. Owner Building at Jimboomba Woods in Logan City Qld. Blog : http://bandlnewhomebuild.blogspot.com H1 thread : viewtopic.php?f=38&t=68283 . Re: 3 Phase or 240V 30Feb 04, 2014 8:53 am I am getting a large AC installed that was why I started this post, but I'm just better informed now of what's actually run to the house. I totally understand the copper is more expensive....we use copper at work ! Re: 3 Phase or 240V 31Feb 04, 2014 9:43 am Through my builder it is a few hundred dollars to add 3 Phase. In addition to workshop and aircons some ovens and other restaurant equipment need it too. I cannot remember the reason or what machinery my folks ran that needed 3 phase but it would have been because my brother needed it. I do not have a choice in my current build as my aircon requires it. I do recall the sparky saying that load can also be split across the phases to balance out. Either way no choice if I want the aircon I am getting, kinda funny since it is meant to be one of the more efficient aircons on the market. Re: 3 Phase or 240V 32Feb 04, 2014 1:37 pm Without a doubt you will need 3 phase with a 19kw Aircon plus an hydronic system. Single phase simply will not cope. Settlement 1/2/12 New Shed 23/3/12 Slab poured 27/3/12 Frame complete 4/5/12 Roof complete 1/6/12 LOCKUP 29/6/12 Our new build blog http://kareenhillsownerbuild.blogspot.com/ Re: 3 Phase or 240V 33Feb 04, 2014 5:21 pm delatite13 Without a doubt you will need 3 phase with a 19kw Aircon plus an hydronic system. Single phase simply will not cope. +1 to that... that's way too much power to suck through single phase, particulary when you are also powering the house from the same phase... 3 phase allows you to run just the a/c on one of the phases, the rest of the house on one or both of the other phases. Owner Building at Jimboomba Woods in Logan City Qld. Blog : http://bandlnewhomebuild.blogspot.com H1 thread : viewtopic.php?f=38&t=68283 . Re: 3 Phase or 240V 34Feb 05, 2014 7:29 am Quote: I'd alter your first bit by saying "if you have to run heavy duty machinery", as most people can run up to around a 280 Amp welder on a single phase house. Considering most people with a welder at home (not talking about professional welding people who work from home), only have up to a 150 Amp welder, that'd be a huge welder I know quite a few tradies and hobbyists who run 3 phase gear at home - lathes, small milling machines, welders, radial arm saws, kilns etc - none of which I'd consider heavy duty as most of them only have 1 or 2HP motors. It is just handy to have especially if you already have this gear. I've got three machines under tarps - power hacksaw ( 1/2HP ), thicknesser ( 2HP ) and a wood lathe ( 1HP ) all laughing at me cos I don't have 3 Phase. The new place will. I agree about the welder though. I just bought a nice little portable Rossi 200 Amp welder that runs off 240 volt, 15 amp and I can weld up to 8mm steel with it. Not disputing the rest of what you say though. Quote: Getting 3 phase power on for the 'fun of it', is a waste of time and money. If you have a need, i.e. large ducted a/c, then it only makes sense. I agree too. The money could be better spent elsewhere on the build. Stewie Re: 3 Phase or 240V 35Feb 05, 2014 1:36 pm Interesting topic We are currently asking the power company to do a underground pit for us (knock down/rebuild), on the application , we do need specify how many phase we want 1 or 2 or 3? Since we won't use refrigerated ducted cooling , but only use the evaporative ducted cooling (the unit mark as 17.5kw though) Not sure whether 1 phase will be sufficient? Re: 3 Phase or 240V 37Feb 05, 2014 2:33 pm Crazyk Scott, They will generally run 3 phase to the pit, then it is up to you to get your electrician to run 3 phase to your meter box. Thanks C Since there are option on their appliaction, I need tick 1 or 2 or 3 phase , so I guess there will be different cost associated with each option as well............ that is why I ask Re: 3 Phase or 240V 39Feb 05, 2014 4:17 pm Scott2233 We are currently asking the power company to do a underground pit for us (knock down/rebuild), on the application , we do need specify how many phase we want 1 or 2 or 3? Since we won't use refrigerated ducted cooling , but only use the evaporative ducted cooling (the unit mark as 17.5kw though) If it's a street pit, then you'll have 3 phase in the pit. Your sparky will hook up the 4 cores up to your meter box, and there's a 3 phase meter to be supplied by your power company. 17.5kw cooler, then you'll definately be going 3 phase to the house. Owner Building at Jimboomba Woods in Logan City Qld. Blog : http://bandlnewhomebuild.blogspot.com H1 thread : viewtopic.php?f=38&t=68283 . 1 62015 |