3phase to single phase current - Page 1
Forum section: electronics / beginners

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 07:17:45 pm
content: Hi all, I have a peculiar situation. At the time my family was building our house; as it's common in our country, we were deceived. I've already repaired an entire floor of electrical instalations (for example guys didn't connect the ground in our sockets (not in the sockets themselves, in the boxes in the walls infact), and then couldn't diagnose it, insisted there was no voltage there, and that my contactless detector was wrong - imagine that. LED lights were still functioning (no idea why, probably such a small current managed to ground itself somehow), and my tesla coil worked, I'm guessing cause it grounded itself wirelessly.) I have also repaired the phone/internet installations that they (I'm guessing on purpose) broke / left disconnected in the walls, most likely so we have to call them again, to charge us again. For their incompetence. We can't sue them, our justice system is broken. We built the house legally even, which is sortof a rarity in our country... so tl:dr : these same douchebags of electricians, told my mom (at the time i knew nothing about the subject) that it's better that we got triphase current. Some lies were told i reckon, why in the world would a family house profit from a triphase solution... Now we have limiters on each phase, such that we cant even cook normaly. Redoing the whole instalations seems out of question now. I guess if I decide to get an industry running in my house, I'm at advantage!So, is there ANY normal way to convert the triphase into normal single one? I've done extensive googling, but any solutions have almost no exeptable efficiency, or those that do, are reeeeeally expensive. Thx for any info/ideas

author: Simon
author_rank: Unknown
timestamp: March 10, 2015, 07:23:13 pm
content: If you take two of the three phase wires on a Delta system all the earth and one of the phases on a star system you can use those as a single phase. What normally happens is that the power is delivered in the form of three-phase and then one of each phase goes to a different street so every third street for example you could get the same phase. It is then hoped that the average consumption of all the houses or balance throughout the three phases. If you have a star system you could in fact put your lights on one phase, your sockets on another or maybe different floors on different phases. That way they would still share the same neutral. The problem you are having with the cooker sounds like a problem with the capacity of the wiring, the safety breaks, or the amount of power being delivered to the house in the first place.

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 07:30:19 pm
content: That's indeed the problem, yes. What you have described is what I did infact, I've tried to rationally distribute the phases around the house. It's how we have "single" phases, and why I can't use powerline ethernet adapters between the floors (different phases). Each phase can give around 10 amps of current or so. So basically, I can't use 12 amps when needed in one place shortly, even though the other 18 are left unused, cause the phase only allows 10, period. What I'm trying to do is infact convert these 10 amps per 3 phase limiters into one phase that could distribute the load between the 3 original phases. Thx for your response!

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 07:36:30 pm
content: The thing is, I have 4 wires. Three phases, and one neutral. So you're saying, I can just connect 2 of the "phase" wires and neutral together, and use that with the remaining phase as a "single phase" system? Not sure that'd work..

author: Monkeh
author_rank: Super Contributor
timestamp: March 10, 2015, 07:40:31 pm
content: Quote from: Benedict on March 10, 2015, 07:36:30 pmFUCK NO.You have 3-phase. That's it, you're stuck with it. That should only be a limitation for ovens and the like, which are easily enough available with low current elements designed for multi-phase installations. That's your only sane option.Sidenote: You had a house BUILT and now you're trying to use PLT? ........

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 07:45:38 pm
content: Quote from: Monkeh on March 10, 2015, 07:40:31 pmThought so. Guess I misred the first reply.When the house was built, I was 7 years old. Don't blame me for getting stuck with that system. It's not just the ovens. In winter, you can't have more than one heater in the entire phase, and that sucks big time. My mom actually bought the thermal insulation, which the builders nicely threw away..I need the stupid homeplugs cause the same guys made it impossible to get the wiring between the floors in some normal way. Ugh it's complicated

author: Monkeh
author_rank: Super Contributor
timestamp: March 10, 2015, 07:47:28 pm
content: Electric heating.With 7.2kVA at your disposal.

author: SeanB
author_rank: Super Contributor
timestamp: March 10, 2015, 07:52:29 pm
content: I take it you are referring to use of an electric stove being the problem, with it tripping the mains if you try to use more than 2 plates together?In that case you simply remove the power connection cover on the back, where you will see that the incoming single phase cable ( line, neutral and protective earth) goes to a 5 terminal block, which is labelled L!, L2, L3, N and then a bolt or another terminal for protective earth. Incoming cable will go to one of L1,L2 or L3 for the line wire ( either red or brown in the cable) and another will go to neutral ( either black or light blue) and the third will be a yellow/green to the protective earth.There will be 2 bridge links ( either a set of jumpers or pressed metal links depending on how old the stove is and where it comes from) combining the L1, L2 and L3 terminals. Simply remove them and wire the stove to the 3 phase power that you have, using a 5 wire flexible cable. that will work to spread the load over the 3 phases when you have more than 1 plate on at a time. You might still have issues using the oven and grill in combination with some plates, but you can simply not use that combination and use another plate.

author: Simon
author_rank: Unknown
timestamp: March 10, 2015, 07:55:51 pm
content: As suggested you may find that your cooker can use all three phases. Alternatively you could potentially rewire it to redistribute power to each element so that they take a phase each although you would need to know what you are doing here.The other main problem is that you only have 30 A in total, I think in the UK any household has a single phase capable of more than 30 A more like 60 A so you are short on power in the first place.As for heating surely a modern house has gas available? Electric heating is quite expensive.

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 07:59:32 pm
content: It's really quite simple. 30 amps + another 30 from the other floor would be more than sufficient to heat anything and have enough current to do whatever you need combined with the central heating we have (it has to be toned down as gas gets crazy expensive and, as i said, I'll have to redo the entire thermal insulation, not sure what to do). We don't live there, so it's not an issue now, still, I'd like to move there one day perhaps. Only nope, i got 10 amps limit on each phase. Not to mention all the other problems. Considering selling the place.Quote from: SeanB on March 10, 2015, 07:52:29 pmThis is great. Thx for that info, might save me a lot of trouble!Quote from: Simon on March 10, 2015, 07:55:51 pmGas is even more expensive for some reason here. At least that's what bills say. I might be wrong, it might even be 16 amps per phase.. That just sucks cause where I live right now, we have basically unlimited single phase current :/Some new law or something. You have to pay to get limits up, a new way to squeze money from people.Thx for your info folks, will help a lot!

author: Phaedrus
author_rank: Frequent Contributor
timestamp: March 10, 2015, 08:01:33 pm
content: I would just redo the entire electric system. Whoever hooked it up in the first place was an idiot, or a scammer. As for selling it, passing this mess off on some other poor Joe seems cruel.

author: M. András
author_rank: Super Contributor
timestamp: March 10, 2015, 08:03:06 pm
content: well you can check that if its fused for 10 amps in the user side breaker panel per phase or its fused 10 at the electricity meter which in case i think you have to contact the utility company to upgrade

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 08:05:01 pm
content: Quote from: Phaedrus on March 10, 2015, 08:01:33 pmThought about that too, I have no idea how much it'd cost to redo everything :SAnd yeh it'd be cruel yesQuote from: M. András on March 10, 2015, 08:03:06 pmAnd that upgrade is off the charts. It's just insane price, especially for three phases, I'd need to get every phase upgraded, and prices are just insaneI was considering something like this :http://carroll-meynell.com/technical-3phase

author: Seekonk
author_rank: Super Contributor
timestamp: March 10, 2015, 08:10:16 pm
content: If you actually have three phase at each outlet, that could be workable. Each outlet could expand to be three circuits. If higher current is needed use a transformer between two phases.

author: SeanB
author_rank: Super Contributor
timestamp: March 10, 2015, 08:12:33 pm
content: Go back to single phase then, and simply get a new meter with a 60A connection. That way you only have to replace the cable from the meter to the distribution board if it is not 16mm cable, otherwise you just reuse it.

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 08:19:19 pm
content: Quote from: Seekonk on March 10, 2015, 08:10:16 pmEach floor has 4 main wires, each phase wire limited to somewhere between 10-16 amps. I think one floor is limited to just 10.Quote from: Seekonk on March 10, 2015, 08:10:16 pmTHIS! How! This is what I was looking for!Quote from: SeanB on March 10, 2015, 08:12:33 pmNever done something like that before, is it generally posible to just ask the provider nicely to give me single phase back?

author: Cloud
author_rank: Regular Contributor
timestamp: March 10, 2015, 08:22:03 pm
content: For how much are rated the main fuses? Do you have automatic fuses or the ones with the melting innercore (diazet). Because through diazet ones can current can be 1.8x higher and it wont brake it.

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 08:23:52 pm
content: All fuses and limiters are automatic. My fuses are not the problem, it's the distributers fuses (limiters) - really fast type ones too. They are, iirc, 10 amps per phase + one neural one (no limit) one floor, and 16 amps per phase + one neutral (no limit) on the other. Voltage is 220 volts.

author: langwadt
author_rank: Super Contributor
timestamp: March 10, 2015, 08:27:07 pm
content: Quote from: Benedict on March 10, 2015, 07:30:19 pmyou are in over your head, your problem has nothing to do with single or three phase.you can't use more than 10A from a single outlet because the wiring and the outlet isn't rated for more and thus there is a fuse of 10Ayou can easily use much more the 10A per phase, but it requires would require several outlets each with separate wiring to the distribution box and a 10A fuse

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 08:30:09 pm
content: Quote from: langwadt on March 10, 2015, 08:27:07 pmNo, you got me wrong. Not the single outlet, no. The problem is that entire rooms (more than 1) and some pumps and what not is on that one 10 amps limiter. I'm not trying to power up the millenium falcon from one of my outlets

author: Zero999
author_rank: Super Contributor
timestamp: March 10, 2015, 08:32:34 pm
content: Quote from: Benedict on March 10, 2015, 08:19:19 pmYes, that will work.Two 10A 230V phases would give 400V at 10A which is 4kVA which would give 17.4A at 230V on the secondary, assuming no losses but in reality it'll be under 17A. Unfortunately transformers are big, bulky and expensive.

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 08:35:51 pm
content: Quote from: Hero999 on March 10, 2015, 08:32:34 pmSo I'm guessing I'm better off forgeting about it?

author: langwadt
author_rank: Super Contributor
timestamp: March 10, 2015, 08:46:28 pm
content: Quote from: Benedict on March 10, 2015, 08:30:09 pmby limitir I assume you mean fuse?if the wiring to that room is only good for 10A there is nothing you can do other than pull more wires each with a separate 10A fuse

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 09:01:06 pm
content: Quote from: langwadt on March 10, 2015, 08:46:28 pmYeah. It is a fuse. But it's called a limiter here, just the technical term for that specific fuse, as it limits what a consumer can draw.Quote from: langwadt on March 10, 2015, 08:46:28 pmAaaand that's what I want to avoid. I see no way of doing that withough drilling through the walls. I was wondering if something like open delta 3 to single exists, and within reason

author: Jeroen3
author_rank: Super Contributor
timestamp: March 10, 2015, 09:09:43 pm
content: Quote from: Benedict on March 10, 2015, 08:35:51 pmYou should ask (and pay) ancertified*electrician (and possibly grid company) if it's possible to install 25A rated 3 phasemain fuseand 16A (3kW)(or less) per branch. Which is common around here, we have 6x16A branches in our house.Living room, first floor, attic, garage, central heating system and washing machine.Assuming you didn't wire up the house with puppy hairs, this might be a realistic and affordable solution.What mm2 and stranding did you use?If the (above ground?) main grid in your street is not able to perform better than 10A per phase per building, you're probably out of luck.*Insurance companies will not pay if he/she was not certifiededit:We keep saying fuse. Isn't a MCB (miniature circuit breaker) better?

author: grumpydoc
author_rank: Super Contributor
timestamp: March 10, 2015, 09:21:05 pm
content: I'm rather confused by the topology here.It sounds like the 10A or 16A "limiter" is actually a fuse or breaker feeding a set of sockets on one floor, this would be about the right value to feed something like 6-8 wall outlets.In which case the supply coming into the house probably is rated at more than 10A per phase.Benedict - perhaps a diagram showing the path from the supply coming into the building, through the meter and distribution boards and to each floor would be helpful. If you wish to use standard colours on the diagram for each phase then neutral is blue and the phases brown, grey and black. As it's an old installation in Croatia chances are the cables are different colours, maybe even non standard or inconsistent. In the UK at least the "old" phase colours are red, yellow and blue.

author: langwadt
author_rank: Super Contributor
timestamp: March 10, 2015, 09:23:11 pm
content: Quote from: Benedict on March 10, 2015, 09:01:06 pmwhat a consumer can draw or what that section of wiring can draw?Quote from: Benedict on March 10, 2015, 09:01:06 pmyou have wires for all three phase in every room?if you only have 10A worth of wiring to room, you won't be able to get more than 10A no matter what you do

author: IconicPCB
author_rank: Super Contributor
timestamp: March 10, 2015, 09:25:55 pm
content: Google Scott transformerGoogle Le Blanc transformer

author: jlmoon
author_rank: Unknown
timestamp: March 10, 2015, 09:27:21 pm
content: QuoteWait now.. no way!!! I have 100 Amps in my 14' x 14' lab. 4 separate quad outlet configurations protected with 20Amp breakers on one wall. Your saying you only have 30 Amps at 240V to work with per floor? How can you survive with that?

author: grumpydoc
author_rank: Super Contributor
timestamp: March 10, 2015, 09:36:23 pm
content: QuoteIt could be worse, in France the standing charge varies with the current limit, which goes up in stages from 3kW so you could find a property there is limited to 15A for the entire houseA few weeks ago I stayed in a property which had a single phase supply limited at 30A/6kW**, it wasn't even anywhere remote but in the centre of a village.**Handily if you push the button on the meter a few times it tells you what the agreed current limit is.EDIT: Way back when I was involved in backstage work at Uni one of the stages had a 60A three phase supply (36kW) - the lighting guy for one of the bands turned up with a rig that needed about 3x the power, looked dismissively at the breakers and said "I've got a bigger power supply to me f***ing bathroom!!"

author: jlmoon
author_rank: Unknown
timestamp: March 10, 2015, 09:43:50 pm
content: Quote from: grumpydoc on March 10, 2015, 09:36:23 pmSo, that explains why I can't see all the country side lighting at night with GoogleEarth. All the bulbs are around 10 - 15 watts max. <Grins>

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 09:52:24 pm
content: I didn't wire anything, have an idea about how thick the wires are but no real number (was 7 when the place was built). I can tell you they have done a baaad job, but it seems that at least the wires are ok.They are single strand, but about 3-4mm in diameter.I've done some research, and it seems the transformers are out of question. Too big, too expensive, too much hassle, for nothing.I checked with the company's website, and it's infact six times 16 amps per branch, as you said. Which is perfectly fine for everything...Unless you account that I have no three-phase outlets anywhere, and only one strand goes to e.g. 2 rooms. That means, if I turn on the heater, or the oven, and my pc at the same time, the circuit will break. Not to mention the sewer pump being on the same strand as the kitchen. Which I found out and rewired.I'd draw a diagram, but I think it's easy enough to explain: One fat main cable from the company to me, branches into 4, one is neutral, other three have circuit breakers (fuses) limited to 16 amps (per floor). Then goes the big box which tells which rooms, lights, etc. are connected to which phase. The problem lies in the fact that whoever did the wiring did a horrendeous job of not getting all strands to some crucial locations, like the kitchen, or at least making some outlest in the room on one phase, and others on the other. Instead, I have a situation in which 2 rooms are wired together, and can't be rewired without breaking the walls (brilliant). The whole kitchen, and the living room, and the bedroom is wired together on one single phase. Insane.So I've found a chart online:http://www.elteh.net/el-instalacije/tablice-limitatora.htmlMine is the lowest in the biggest chart, I have the 16/16/16 times 2, that'd be 11,04 kW x2. on 6 strands. Which means that while most of the power is useless, when you have to use for example 20 amps in 2 rooms which are wired together, boom nope. Terrible. And the kitchen too. Considering that my old place, a 100 year old building now, has the better wiring and, I think doesn't even have a company limit... sighAnd to upgrade, I'd have to cash out around 250/300 euros per 1kW, and it's only available from these options. The first table is the single phase. It might be possible to switch to that, seeing that due to the horrendous wiring, it's that or the rewireing the whole place. Which is .. you know.. really bad.As i said, even if the wires were only 2mm, it's still enough for 20 amps or so, and they are deff. around 3 or 4 mm. Only prob is that they are really really badly connected, just in twists and insulating wire. That needs to change fast, I think.So everyone, thank you very very much for helping me sort this out. I think I can do it from here on. Really, thank you all.

author: langwadt
author_rank: Super Contributor
timestamp: March 10, 2015, 10:09:12 pm
content: Quote from: Benedict on March 10, 2015, 09:52:24 pmJust to sum up so you don't burn down the house.If the wiring from the fusebox to the outlets in several rooms can only 10A it doesn't matter if you have3x10A or 1x30A, those rooms can still only use 10A

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 10:12:31 pm
content: Hehe, thx for the warning. True, true. I think they are good for 50-60 amps or so, so no worries. I'll be certain to tripple check.

author: Benedict
author_rank: Regular Contributor
timestamp: March 10, 2015, 10:13:56 pm
content: Quote from: langwadt on March 10, 2015, 10:09:12 pm

author: Jeroen3
author_rank: Super Contributor
timestamp: March 10, 2015, 10:29:59 pm
content: Everything here is solid 2.5mm2. Thermally protected to 16 A type B per branch.Tables say 22A, but in a wall next to other cables you must derate. I shall look this up in the reference guide tomorrow.

author: max666
author_rank: Frequent Contributor
timestamp: March 11, 2015, 12:33:41 am
content: Reading through this thread is bizarre!I too just want to say, that there is nothing wrong with three phase installations in general, here in Austria every household gets three phases only (as far as I'm aware).You say you now have the three phase plan 3 x 16 A / 11,4 kW (Tropolni limitatori za trofazni simetri?ni priklju?ak). But if you want to switch to one phase (Limitatori za jednofazni priklju?ak), you would have to get the 50 A plan to have the same 11,4 kW power rating. How much would that cost? Is the 1P 50 A / 11,4 kW option cheaper than the 3P 16 A / 11,4 kW option? I wouldn't think so.Check your stove/baking oven, get the manual, or pull it out and look on the backside, if it can be connected with three phases. Most stove/baking ovens can be wired in various ways, like SeanB already explained nicely:And if you have three phases coming in the door, then you should wire three phases to the stove/baking oven. Even if you switch to on phase, the oven should still be wired separately, with a separate circuit breaker, and should not just hang on the whole kitchen circuit as well. So if you don't have the wiring to the stove, you would need to pull separate wires anyway, regardless of how many phases you have.All the other rooms and devices get as evenly as possible distributed over the three phases as well. Since I'm at it, a dishwasher, a washing machine or a dryer, each should have a separate wiring of 2.5 mm² cross-sectional area to a separate 16 A breaker. And all the separate 16 A / 13 A / 10 A breakers are connected to the main circuit breaker (which could be 3 x 16 A, although for a house that is pretty weak). Make yourself familiar with wire gaugehttp://en.wikipedia.org/wiki/IEC_60228(not the best link, sorry), saying the wire is 3 mm thick doesn't mean anything. For example my oven has the following options and depending on that can have different wiring:Now what is up with that heating? You aren't heating the house electrically, from the three phases, are you? That would be ridiculous, heating a house from 3 x 16 A, which by the way would make no difference if you had 1 x 50 A. Heating a house from 1 x 50 A is equally ridiculous. And heating electrically is the worst thing you can do, electricity is the most expensive energy carrier in terms of kW/€. But there is a big difference between heating your home electrically and cooking your food electrically, so just to clear that up what you actually do.Also a picture of your main circuit breaker / fuse box might give us a better understanding too.

author: Benedict
author_rank: Regular Contributor
timestamp: March 11, 2015, 12:46:52 pm
content: Oh. Let me try to explain. What you speak are some valid points. Mostly not in my situation.Quote from: max666 on March 11, 2015, 12:33:41 amShould be exactly the same in price. I hope.Quote from: max666 on March 11, 2015, 12:33:41 amWhen you have the central heating of an object that is 350 meters squared of space, heating a living room and bedroom on one floor only, is much much better than heating the whole place with gas, when the rest of that space is "useless",don't you think? Closing the valves on all the other water radiators won't work, the thermostat is in different rooms/floors even. The house is broken. I'm trying to fix it/ make it usable at least for the time being. Why is the house so uselessly huge? I WAS 7 WHEN IT WAS BUILT not my faultQuote from: max666 on March 11, 2015, 12:33:41 amThx for the idea! It was mentioned already, will try it. HOWEVER, the whole kitchen, and one living room with it are wired on the same phase. There simply are not enough wires! Each outlet is a single phase one. As I said I don't have a single three phase outlet. Even if I did, the wiring in the house forbids it! I'd have to break down walls to correct that, I just might even have to eventually! It's terrible! My only hope is that these three outlets in the kitchen are somehow not wired together, and that I can rewire them on different phases. Somehow I have hope, we'll see. (Doubt it)

author: mzzj
author_rank: Super Contributor
timestamp: March 11, 2015, 02:03:35 pm
content: Quote from: SeanB on March 10, 2015, 08:12:33 pmLike there would be a choice in many(most?) european countries.Here in Finland pretty much all the houses built in last 70 years are connected to 3-phase. 3x 25A or 35A main fuses are the norm. And all the power-hungry equipment is 3-phase. 9kW sauna stove, 6kW kitchen stove, 12kW for central heating etc.OP should redo the wiring, I guess you should be able to find more competent electricians nowadays. Run a 3x16A cable for the stove and so on.

author: max666
author_rank: Frequent Contributor
timestamp: March 11, 2015, 03:56:13 pm
content: Ok so to get this perfectly clear, you DO HEAT the house electric (at least part of it), and when you turn on the stove, the breaker trips?While you may have to pay less for a partially heated house on electric, than on a fully heated house on gas, I give you that, it's still not an optimal solution. But hey, customer is king here at the EEVbogYou could give us a count on how many heaters you have and how much kW they have, but I stand by what I said, heating and all the rest on 11,4 kW regardless of 3 x 16 A or 1 x 50 A, is ridiculous.But hey, since you like tightrope walking, one thing you could do is get a clamp-meterhttp://www.batronix.com/shop/multimeter/clamp-multimeter.htmland measure the currents on your 3 phases and then start juggling(the clamp-meter has the advantage that you don't have to disconnect phases for measuring the current)Perhaps you can balance them out.Since getting more than 11,4 kW connection is out of question, another thing you could do is wire the heaters on acontactoror individually on relays and have the heaters turn off when you turn on the stove or automatically when current on a phase exceeds a limit. This would actually be a solution that I kinda like, because it would allow you to maximise degree of capacity utilisation (which is to say you get the most out of your measly 11,4 kW connection). And turning off the heaters for a few hours is no big deal, because the thermal mass of the walls can bridge that.I still would like to see how the stove is connected, how much power the stove has, if it is on the same circuit as the kitchen and what gauge of wire is used ... you know, burning down the house and safety and shit.I'm not an electrician, but if they've used a 2,5 mm² wire (which should be good for 16 A, I guess) for the stove, kitchen and another room, and you're going to switch to one phase and you're connecting that all up to a 50 A breaker without checking the wiring, then you're on your own kid!!!

author: M. András
author_rank: Super Contributor
timestamp: March 11, 2015, 07:10:14 pm
content: There should be plastic conduits in the wall where the wires are pulled in, remove 1 of the sockets carefully and check whats in there and if the wires move at all, if it moves a bit you can pull in new ones and if the plastic pipes are big enough you can even pull in more or thicker wires, get a new distriution box and split the circuits so you can use multiple things at once.The upgrade is sounds a bit costly on your end, it would cost me approx 310 euros to 3x25A infeed, apart from the rewiring of the whole building cos the 40 your aluminium wiring is now undersized and badly cooked joints slowly becoming a problem. that would be serious money which is split into 4 as its a 4 flat building, like 6-7 times what the upgrade would cost me after thatI have 3x16A 240v infeed which after the electricity meter is split into 20 circuits now eahc fused separately each phase goes trough 25A A-Si type schneider electric RCD-s then branched out to rooms, the only thing isnt protected by them is the stove as it runs off from 2x240v supply and i didnt brother to buy a 3 phase RCD for this, installed a 3ph+n surge arrestor too the catridge type as we had lots of damage last summer in a big storm all this is put into a 2x24 module schneider pragma enclosure, expensive and big but you cant beat the servicability of that breaker box,

author: IanB
author_rank: Super Contributor
timestamp: March 11, 2015, 07:22:35 pm
content: Quote from: M. András on March 11, 2015, 07:10:14 pmThis is not always the case. Sometimes the wires are just buried in the mortar.

author: KJDS
author_rank: Super Contributor
timestamp: March 11, 2015, 07:30:47 pm
content: Quote from: IanB on March 11, 2015, 07:22:35 pmI've seen many configurations, including clipped to the wall, then covered with a plastic trunk then plastered over, to left dangling free behind dot and dabbed plasterboard to straight plastered over.Everything added to the last house I was in was put in the easiest way possible, so some sockets were mounted on the wall with a feed coming in from a socket on the other side of the wall. Others were mounted very close to the floor and the wiring channeled into the wall and then plastered over.

author: M. András
author_rank: Super Contributor
timestamp: March 11, 2015, 08:25:51 pm
content: Quote from: IanB on March 11, 2015, 07:22:35 pmyeah but there should be, in my case we have nice little 16mm od plastic pipes in the walls, at every corner and joints it was broken into the wall then fixed with gypsum had to hammer out every corner when i redid the wiring, in the kitchen it had a 3cm long open section in the pipe which was full of gypsum so no way to pull out even the original wires, hope the drunk dude who did the originals installations is below the ground now by electrocution

author: G7PSK
author_rank: Super Contributor
timestamp: March 11, 2015, 10:12:39 pm
content: Quote from: blueskull on March 11, 2015, 09:30:27 pmScott transformer is what is normally used to convert 3 phase to single phase.

author: IconicPCB
author_rank: Super Contributor
timestamp: March 11, 2015, 11:23:27 pm
content: Blueskull,Earlier in the post I pointed to Scott transformer as well as to LeBlanc transformer.Google is Your friend.

author: Benedict
author_rank: Regular Contributor
timestamp: March 12, 2015, 12:20:32 am
content: Well, mum said she bought the plastic conduits, and found them throwing those away and just diping the wires into mortar. So, good job there. Though, that was for the coax ones.. Perhaps, and I do hope so.. the electric wires aren't. Will have to check it, it just might be possible to do the wires again, in which case I'm gonna install tanks in the walls. That house is just a nasty nest of problems

author: Zero999
author_rank: Super Contributor
timestamp: March 12, 2015, 10:33:11 am
content: It's not possible to use a transformer alone to draw power equally from all three phases and transmit it to a single phase.A rotary converter (very bulky, mechanical so unreliable and inefficient) or rectifier plus inverter (better than a rotary converter but less efficient and not as tolerant of overloads as a transformer) are the only ways to do this.

author: Jeroen3
author_rank: Super Contributor
timestamp: March 12, 2015, 02:31:00 pm
content: Here you go.http://www.schaeferpower.com/content/content/acac-frequency-invertersYou have to ask the price. Which means its very expensive.