Recent content by Tetris1985

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    Working out the length of a ring finals circuit

    Ah that Makes sense, I would of thought it would be cut and dry with regards to exceeding VD, that's what im struggling with ....for a RFC is the design current always 32 or (26) or could you have a design current of 25 but still have it on a 32 amp mcb or rcbo?
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    Working out the length of a ring finals circuit

    So in this case where it is compliant on a 20 amp, compliant in terms or ZS and VD but not reg 433.1.204 it would be a c3. Would it be a c3 or c2 if it was on 32 amps complied with ZS but VD was 7.5% in your opinion?
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    Metal back boxs and r2 reading

    Might be a dumb question, but do metal back boxs have an effect on the R2 reading I feel like they dont as when you times r1 or rn by 1.67 you get the expected r2 of the cable
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    Working out the length of a ring finals circuit

    you would not be concerned with the at 32 amps? is that because the VD is only a few percent over ? or becasue you doubt they would ever be loaded that much to reach 32 amps?
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    Working out the length of a ring finals circuit

    Regulation 433.1.204 seems kind of dumb where it states the 30 / 32 amps on a rfc dropping the mcb rating does not make it less safe, does it? I mean you can get 25amp mcb now I feel like it should mean you can use 32 amps on a ring wired in 2.5mm even though the cable is rated lower than 32...
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    Working out the length of a ring finals circuit

    Learning I have done a level 2 and 3 and working on my NVQ. I have started working with my dad who is QS and old spark and he brought a new property and has let me test it to get some real world experience before he tests its. ( its empty I cant hurt anyone ) why cant you comply with the regs...
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    Working out the length of a ring finals circuit

    Thanks for the reply its educational to say the least. I found a ring of 151 meters and one of 135 meters so they are both over the range for VD The longest one feeds two bedrooms and the shorter one feeds a front room and hallway Leaving them on 32 amps does not sit well with me. They meet...
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    Working out the length of a ring finals circuit

    I'm getting there with it but a drop of 22 volts on a rfc is a fail of vd? So if you used a 16amp mcb on a rfc the formula would stay the same? But in the above case the vd would then comply What would happen if you exceed VD than say less than 10%
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    Working out the length of a ring finals circuit

    So it would go something like this? (1.15 + 1.80) / (19.51/1000) 2.95 / 0.01951 = 151 meters so this to work out the voltage drop it would then be Voltage Drop = ( mV/A/m ) x L x Ib / 1000 18 x 151 x 32 / 4 = 21744 / 1000 = 21 volts does not comply with voltage drop
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    Working out the length of a ring finals circuit

    r1: 1.15 r2: 1.80 rn: 1.15 r1r2 0.69 To work out the length of a ring in 2.5mm twin would this be correct 0.69/(19.51/1000) = 35m or would you use the r1r2 before you divide it by 4?
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    Eddi currents and conduit

    Its about 1 to 1.5 meters of round conduit.
  12. T

    Eddi currents and conduit

    On a domestic Cu 60 amp would live and nuetral tails cause eddi currents of any significants if the tails were run in sperate metal conduit but then run through the same tails gland at the cu? IM sure the answer is yes
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    Metal ceiling grid voltage

    What would be the solution? When the ceiling is bonded you can get a very small shock if you touch the panel screws and the metal grid. but testing between the screws to the ceiling reads 0 volts but I'm guessing with a multi meter that reads dc it would give a reading? if you test from the...
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    Metal ceiling grid voltage

    The drivers are class 2 yes If you test from met to a metal screw on the unit you get any where between 15 to 50 volts And met to ceiling grid 100v If you bond the ceiling you get small sparks when the panel touch’s the grid when the circuit is on Same small sparks if you connect the bonding...
  15. 5AC285C5-65A5-4FFC-B1E0-2FC711945325.jpeg

    5AC285C5-65A5-4FFC-B1E0-2FC711945325.jpeg

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