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Anyone Know Anything About Electrics? watch

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    (Original post by dave134)
    How much of the regs is single phase only?

    The maths behind 3-phase needs complex numbers to be easily understood!
    I have never seen a copy of the IEE wiring regulations but I do have general wiring books which qoute IEE.

    For most people I guess only single phase is really relevent although. In buildings I suppose an electrical engineer who will understand everything will tell the sparks what to do. I thin its this area where my uncle works, he basicaly advices people about the electronics of a huge neclear recycling plant. He has countless degrees (masters etc) to enable him to that job.
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    (Original post by amazingtrade)
    I have never seen a copy of the IEE wiring regulations but I do have general wiring books which qoute IEE.

    For most people I guess only single phase is really relevent although. In buildings I suppose an electrical engineer who will understand everything will tell the sparks what to do. I thin its this area where my uncle works, he basicaly advices people about the electronics of a huge neclear recycling plant. He has countless degrees (masters etc) to enable him to that job.
    Connect the red phase to the blue phase....... BZZZZZZRT!

    Apparently somebody had to be rushed to hospital in Durham after not understanding 3 phase. The main ballroom has 125A 3Ph (3P+N+E) for the lights. There are also some boxes that split the 3Ph into 3 lots of 240V 1Ph. This guy plugged some consumer device into red phase, and another consumer device into blue. They were connected by an audio cable.
    The insulation couldn't cope with a potential difference of 415V, and sparked. He was thrown across the ballroom
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    (Original post by dave134)
    Connect the red phase to the blue phase....... BZZZZZZRT!

    Apparently somebody had to be rushed to hospital in Durham after not understanding 3 phase. The main ballroom has 125A 3Ph (3P+N+E) for the lights. There are also some boxes that split the 3Ph into 3 lots of 240V 1Ph. This guy plugged some consumer device into red phase, and another consumer device into blue. They were connected by an audio cable.
    The insulation couldn't cope with a potential difference of 415V, and sparked. He was thrown across the ballroom
    I imagine that many mistakes will occur now the 3 phase colours are being changed - RYB are going to Brown, Grey and Black with Blue as neutral. Although arning lables are going to be used it will be an interesting time.
    I personaly would not touch 3ph unless I am certified - I do not fully understand it so it is outside of my limits.
    However, for this job there will not be extreme danger. At the moment I am planning on:
    50A MCB on house CU
    16mm^2 armoured to shed - buried in a 300mm deep trench
    Consumer unit in shed with:
    50A 30mA RCB protecting
    2 16A MCBs for 2 wall heaters
    1 6A mcb for lights
    1 32A MCB for a ring socket main
    1 6A mcb for an alarm - if fitted.

    Based on calculations the max power drawn will be 10kW, pulling about 45A - inculding voltage drop for long run.
 
 
 
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