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Thread: 3 Phase or 1 Phase.

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    Bronze Member mikilianis's Avatar
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    3 Phase or 1 Phase.

    Regarding the electrical supply to a domestic dwellings.
    Some of the older houses in Cape Town have a 3 phase supply and the more modern ones have a 1 phase supply. Are there any advantages to having a 3 phase supply? What I am trying to query is whether it is worthwhile converting the dwelling into a single phase or just leaving it as 3 phase. I am often asked this question

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    there are only 2 advantages having a 3 phase supply at home...

    one 60 amps across the 3 phases which means you can have a total load of 180 amps...houses which have jacuzzi...pool...ducted aircons...etc etc...which use more than 80 amps need 3 phase power...they will not give you more than 80 amps single phase.

    and the other is if you have equipment which can only run on 3 phase.

    my advice if you lived in durban would be to keep it 3 phase...you ask why... because to increase from single phase to 3 phase would cost you around R25000.00 and if you already have it i wouldnt change it...unless the meter charge is higher.

    i always thought if the load wasnt balanced you paid more...but this is not the case...the meter measures each phase...

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    Diamond Member AndyD's Avatar
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    I don't see any good reasons to convert from three phase to single phase. As Murdock says, three phase can be an advantage to some consumers.
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    Gold Member Martinco's Avatar
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    Quote Originally Posted by AndyD View Post
    I don't see any good reasons to convert from three phase to single phase. As Murdock says, three phase can be an advantage to some consumers.
    Leave it as it is.................you will have to pay for a new meter (?) and have the DB redone, and besides, it is like swapping your 2010 Merc.with a full tank for a 2010 i20. and still having to fill up the i20. ( I have nothing against the Korean make, but just to illustrate )
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    as long as the 3 phase supply is not too low .i have seen quite a few 20 amp 2,5mm 3 phase supplies in older areas like obs and woodstock.you would have load balance very carefully.

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    Diamond Member AndyD's Avatar
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    Quote Originally Posted by bergie View Post
    as long as the 3 phase supply is not too low .i have seen quite a few 20 amp 2,5mm 3 phase supplies in older areas like obs and woodstock.you would have load balance very carefully.
    Ah, this could be a different story I've only seen 50Amp domestic 3-phase supplies, if it's a 20Amp supply it would be a major problem to balance and avoid overload tripping.
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    Gold Member Martinco's Avatar
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    Quote Originally Posted by bergie View Post
    as long as the 3 phase supply is not too low .i have seen quite a few 20 amp 2,5mm 3 phase supplies in older areas like obs and woodstock.you would have load balance very carefully.
    Sounds as though these were the ones brought along on the Nina , Pinta and Santa Maria !
    Martin Coetzee
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    you should see the dis.boards in those old houses.a lot are still original,always installed in the passage just as you walk in the front door. you have to walk sideways to get around it. a big wooden board 2m high to fit the kwh meter. earth neutral connections,big fuse boxes,seperate fuse box for the stove. plenty of single core wire outside the boxes. some with no mods since new,except the "blou draad" fuse wire.no earth leakage relay,etc murdoch would have a field day with his camera

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    this is what amazes me about electricity...maybe the standards need to be changed back to what they were 100 years ago...the reason i say this is because the majority of fires i go to are normally new installations...new plugs over loaded and loose connections in new installtions...or installtions where the sparkies of today have worked on them...old installations dont fail it the ones which have been upgraded or tampered with by sparkies from this era.

    the most recent fault finding i did on a building...the fault was found in a junction box mounted in the wall more than 20 years ago...all old parts of the installation are still in tact up to standard and working...however the new work which was done recently is didnt pass...for example a small hole is drilled in the side of the fitting with no glands the hole is a s rough as can be...the circuit house wires are squashed up against the ceiling under the light casing and pulled in thru the hole in the top of the fitting...

    anyway as i have said in the past i was called out to trace a fault in the building not to do an inspection report...i pulled my blinkers closed and did what i was contracted to do...easy for some people on this frorum to say it not the right thing to do but i have an idea...anyone who feels this is not the right thing to do please give and order number and 70 % deposit of R62196.12 and i will start making people more aware of their problems write reports of all the bad installations i find on my daily rounds otherwise be my guest join me on my daily rounds and i will leave it up to you to gather all the information and waste your time sending them to the DOL or AIA and you can
    feed your family...

    pay your bond or ease...

    telephone account...

    accounting fees..

    vehicle lease...

    petrol...

    vehicle maintence...

    staff wages...

    taxes...

    uif...

    bargaining councils fees...

    medical aid...

    year end leave pay and bonuses...(which i am sure everyone is looking forward to...most small company owners will be enjoying time at home this year because there will be no money left when they are finished paying out teir staff and some will be selling stuff to come up with the money)

    just to mention a few of the obligations we as company owner have to come up with... with the money you generate from the task.

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