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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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  • 0

    I'm just going on what the carrier says. How do you find out the fuse rating? 

    Well as you have just rewired, presumably the main fuse came out to make the CU safe to work on, so by looking at it while i t is out. At that point out comes the sharpie pen and writes the value on the board beside it, and maybe the zs result.

     If the DNO came and took it out for you, or if you did, and what happened to the seals is a matter of conscience, and the policy of the DNO, some will issue paper seals to folk they trust, others do not. 

    Do not get too worried by max demand calculated as per the OSG - it over-estimates, substantially, and in practice 16mm tails on a 100A load will not suddenly burst into flames. They may last 25 years instead of 50 if the house is fully loaded, but the electricity bills means it probably isn't going to be. 

    Mike.

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  • 0

    I'm just going on what the carrier says. How do you find out the fuse rating? 

    Well as you have just rewired, presumably the main fuse came out to make the CU safe to work on, so by looking at it while i t is out. At that point out comes the sharpie pen and writes the value on the board beside it, and maybe the zs result.

     If the DNO came and took it out for you, or if you did, and what happened to the seals is a matter of conscience, and the policy of the DNO, some will issue paper seals to folk they trust, others do not. 

    Do not get too worried by max demand calculated as per the OSG - it over-estimates, substantially, and in practice 16mm tails on a 100A load will not suddenly burst into flames. They may last 25 years instead of 50 if the house is fully loaded, but the electricity bills means it probably isn't going to be. 

    Mike.

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