New supply tails in trunking or SWA?

[Engineer54]

I realise that for most modern houses, fusing down to say, 40A, would probably be impossible due to the power requirements at certain times (shower/cooker etc)

The average domestic installation with gas central heating, without electrical shower unit, would rarely see 40A at the meter. My parents house had a 60A cut-out fuse and a 40A meter. They were both changed (80A fuse and 100A meter) in 96, but had never had a problem with either!! ...lol!!!

 

[GaryM]

I've seen 1.6:1 and even 2:1 mentioned for fuse discrimination. Based on that you wouldn't achieve discrimination using an 80A fuse with a 100A main fuse, you'll be needing a 63A or even a 50A fuse.

 

[Guitarist]

Personally, provided the cabling is protected, I would go for the maximum fuse to match the main incomer. Let's face it, how often does the 100A or 60A main fuse actually blow? Why should we restrict the customer's supply potential for the chance at providing the possibility of genuine discrimination on the rare occasion that a fault would take the mains out anyway?

 

[GaryM]

Personally, provided the cabling is protected, I would go for the maximum fuse to match the main incomer.

So would I.

 

[ChevyKevv]

So would I.

It turns out the main fuse is only 60A anyway, this on a house built in the 1990's so i'm going for a 60A in the fused switch.

 

[GaryM]

Sounds good to me.

 

[shocking_eg]

so if the DNO fuse blows - change the bugger and no one would know - saying that, had one blow in a ryefield board before, customer phones DNO, they came out within an hour and changed it for free !

not sure if its usually a freebie ?

 

[Darkwood]

so if the DNO fuse blows - change the bugger and no one would know - saying that, had one blow in a ryefield board before, customer phones DNO, they came out within an hour and changed it for free !

not sure if its usually a freebie ?

Not the wisest post, in that you are suggesting the OP commit an illegal act, might give the wrong impression to any member of the public about what we stand for,.... yes agree! it happens but could have been worded as a play on words.....( If only you were allowed to replace the service head fuse yourself )