Wiring diagram correct for 63A RCCB and 50A MCB?

Discussion in 'Electrics UK' started by Buzzcut, 4 Dec 2009.

  1. Buzzcut

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    Afternoon...

    I've just bought a new place and scarily there's no RCD on the 10.8 kW electric shower. I had a sparky in to check a few things out and he said to get a standalone 50A 30mA RCD unit that goes next to the CU (rather than replace the whole CU which is a bit old).

    I've got one but would it be bi-directional i.e. can I switch the In with the Out. My feed from the CU is from below but does that still have to be wired into the top of the RCCB as drawn below? Common sense tells me that it can be wired either way but I'm not 100% sure.

    See here for the wiring I'm planning.. http://www.filedump.net/dumped/mcbrccb1259943821.jpg

    Cheers for any advice you can give. I'll get a whole new CU once funds allow but I just want to protect the shower at the mo.

    Buzz
     
  2. Steve

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    No. Wire it correctly.

    Is your electrician coming back to test this RCD?
     
  3. Buzzcut

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    ..and correctly would be??

    He'll check it when he wires in the heated floor next week.
     
  4. Steve

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    Supply in the top of the RCD.

    Shower wired to the N of the RCD bottom, and L of the 50A MCB.
     
  5. Buzzcut

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    Thanks, Steve

    So the drawing was correct only if the supply was coming in the top.

    There's a bar already connecting the L RCD load to the L MCB supply.

    Much appreaciated.

    Buzz
     
  6. flameport

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    I suggest you get a larger enclosure, that one is barely big enough for the devices and it will be extremely difficult to get 10mm cables in there.
     
  7. ban-all-sheds

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    There'd be more space if the pointless MCB were removed.
     
  8. Taylortwocities

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    :?: Do you think that CDL7-63 thingy is an RCBO then?
     
  9. mfarrow

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    I think BAS was trying to point out that the shower is already fed from the CU - therefore should already be protected by an MCB/fuse.
     

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