Looped Supplies

[m4tty]

Hi,

Just wondered how often you lot came across looped supplies. With the incomming cable coming into one property (semi/terraced) being looped through the wall to next doors property.

How is the cable fed through to next door. Does the incomming cable go into one property into henly block then both properties fed through mainfuse from this. I ask this question as years ago I was told that someone on a looped supply blew their neighbours mainfuse leaving theirs intact. So they must be in series? as if the first fuse didnt blow but the one further down the line blew as two 60A BS88/BS1361s wont discriminate between eachother? correct?

Thanks in advance for any input. Any information on looped supplies would be appreciated as im trying to learn and understand this.

Cheersut the kettle on

 

[Nicky Tesla]

it wont be in series.

you are best to make your property tt or make a visit next door to check it out and then make a judgment.

 

[Andy™]

its usually looped at the service head - it has terminals for in & out (unfused), along with fuse for property. but i have seen service heads with 2 fuses, one for the next property. in this case, the loop is sometimes terminated internal to the head, or external (connected like tails)

 

[m4tty]

Thanks for the replies andy/nicky . Ive been next door and had a look and think my only option is to tt it. Anyone had any experience of putting a rod in under the floor in a terraced house where it's clay as the run to get outside ain't gonna happen. Thanks

 

[m4tty]

Lol I tried banging a rod in under the floorboards under the stairs but the oversight is far too hard. Tried drilling it with no joy so I've banged a rod in out in the garden next to the soakaway and managed to get a loop Reading of 29.4 ohms. Is that called Ra? Is that Reading good ? Well under 200 ohms so I believe it's ok. If I run earth cable from new db to rod is it ok to run it in conduit with the garage supply cables and will it need mechanical protection where I run it under garden to where rod is?

Thanks

 

[M107]

Lol I tried banging a rod in under the floorboards under the stairs but the oversight is far too hard. Tried drilling it with no joy so I've banged a rod in out in the garden next to the soakaway and managed to get a loop Reading of 29.4 ohms. Is that called Ra? Is that Reading good ? Well under 200 ohms so I believe it's ok. If I run earth cable from new db to rod is it ok to run it in conduit with the garage supply cables and will it need mechanical protection where I run it under garden to where rod is?Thanks

You'll probably find the houses are built on concrete rafts, most of the terraces my way are like that.

29ohms is spot on for Ze (Ra). I take it you have disconnected from MEB's before undertaking the test .

It's fine to run MEC to the rod in conduit along with circuit conductors.

Use 10 or 16mm & no protection is needed if buried, but looks better if buried & using the enclosure I've linked to in your other post you can tube right to the rod.

 

[Apache]

Lol I tried banging a rod in under the floorboards under the stairs but the oversight is far too hard. Tried drilling it with no joy so I've banged a rod in out in the garden next to the soakaway and managed to get a loop Reading of 29.4 ohms. Is that called Ra? Is that Reading good ? Well under 200 ohms so I believe it's ok. If I run earth cable from new db to rod is it ok to run it in conduit with the garage supply cables and will it need mechanical protection where I run it under garden to where rod is?Thanks

You've hit the water main Matty!

 

[m4tty]

:^O

 

[springcrocus]

[quote name='Andy

 

[SLIPSHOD & SLAPDASH]

Luckily i dont have to do many TT jobs. Today we had a large Temporary genny install and i sunk 2 rods in 4m deep and the best i could get was 1350 ohms. Have to look at getting it better tommorow.

 

[sparkytim]

30 m A RCD ?

Not ideal but still complies.

BRB

pG 50

 

[Andy™]

Luckily i dont have to do many TT jobs. Today we had a large Temporary genny install and i sunk 2 rods in 4m deep and the best i could get was 1350 ohms. Have to look at getting it better tommorow.

still not a TT supply, but either way, thats one high reading! whats the ground made of?