Supplier fuse query/DNO

[diditrain]

Went to replace a consumer unit today and removed the service fuse. Lady from next door said her electric had gone off and sure enough, when fuse is removed it cuts off both properties. Rang the DNO and they said that it is not a problem. Surely this is unacceptable?

 

[Pat H]

Presumably (hopefully) its split before the meter. So effectively a multi occupancy supply?

 

[The Ghost]

It is very common to have a TN-S supply looping to next door just make sure next doors earth is not on your house calls earth bar. I would be careful about saying you pulled the DNO fuse you never know who is reading!

 

[Taylortwocities]

It is very common to have a TN-S supply looping to next door

Yes, but I haven't seen it done after the fuse? Maybe I need to get out more.

 

[Pat H]

I think the OP meant the DNO fuse wasn't seated right and he wanted to ensure no damage had been caused and to reseat it correctly

 

[sparksburnout]

It is very common to have a TN-S supply looping to next door just make sure next doors earth is not on your house calls earth bar. I would be careful about saying you pulled the DNO fuse you never know who is reading!

If they were not bothered when he rang them up they won't be bothered on here will they!

 

[The Ghost]

he didnt tell them he pulled the fuse

 

[diditrain]

There was an earthing conductor running into next door aswell as the tails. I have never seen two houses protected by the same service fuse before though, hence my post.

 

[The Ghost]

I have in 1940's houses usually, it does seem bad that two house are on one fuse. But DNO march to their own drum beat.

 

[Wilko]

As I understand it, the suppliers fuse is primarily to protect the suppliers cable so they can do this. Hopefully services split before the meter and main protective conductors are from the TNS cable cut out and not upstream at the CU. If I may ask - what was the service fuse size and how long are the neighbours tails do you reckon?

 

[diditrain]

Tails are no more than 1 metre, 16mm csa. next doors is back to back, where they go into another service head/fuse. They are split before the meter. I think the fuse was 100amp, but will have to double check when I return. Job was postponed for the time being.

 

[7029 dave]

Yes the cut out can be loop in to other property, but only on supply side.If you withdraw the fuse it should only prove dead to that property in question. eg 100amp feeding both that is wrong.

 

[Stu1312]

Lots of old supplies have one fuse feeding two meters/supplies. Most common in houses split into two houses with a rising or later main to the second meter. Meter operators won't install a new supply on a shared fuse but will exchange the meters as the dno's are not obligated to change them to seperate fusing.

 

[7029 dave]

Lots of old supplies have one fuse feeding two meters/supplies. Most common in houses split into two houses with a rising or later main to the second meter. Meter operators won't install a new supply on a shared fuse but will exchange the meters as the dno's are not obligated to change them to seperate fusing.

Yes classic with maisonettes, shared fuse. But next door?

 

[diditrain]

What if the first fuse ruptures, whilst your neighbours are on holiday? maximum demand assessment etc.

 

[Stu1312]

Yes classic with maisonettes, shared fuse. But next door?

Not usual but have seen it a few times. Most we've had was 9 flats/offices off a 200amp three phase head fed direct to all properties with no sub fusing just straight out of the MI pot at each meter. Only one office had access as it was in there basement.