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Incoming supply cable and 16mm/25mm tails questions

Jimi

Hi, I've rewired a property, 100A main fuse, 2 electric showers plus everything else so maximum demand is potentially over 100A in theory. I added a main isolator and used 25mm tails to the CU. The distributors tails look slightly smaller so I'm assuming 16mm unless the sheath is thinner. 

Does everyone report if there are 16mm tails on a 100A main fuse? Why did the distributor not put 25mm tails in when they put a 100A fuse in? Does anyone know what size the conductors of the actual incoming cable are? If less that 16mm does that mean digging the street / house up to replace it with 25mm? 

Thanks!

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    broadgage: 
     

    If in doubt, simply ring the DNO, they will be happy to replace the fuse with a smaller one, and probably wont even charge for this.

    Then if the next owner of the property wants 100 amps they can charge hundreds of pounds for the improvements.

    The maximum demand is a fair amount over 100A if I use table A1 and A2 of the OSG. Never a clear answer with electrics is there. I remember some of the guidance I've read if ‘for installations up to 100A’ and I don't know what needs to change when over 100A anyway. Maybe I'll choose jobs <100A maximum demand for now.

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  • 0

    broadgage: 
     

    If in doubt, simply ring the DNO, they will be happy to replace the fuse with a smaller one, and probably wont even charge for this.

    Then if the next owner of the property wants 100 amps they can charge hundreds of pounds for the improvements.

    The maximum demand is a fair amount over 100A if I use table A1 and A2 of the OSG. Never a clear answer with electrics is there. I remember some of the guidance I've read if ‘for installations up to 100A’ and I don't know what needs to change when over 100A anyway. Maybe I'll choose jobs <100A maximum demand for now.

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