Homeowners who have discovered they have a 'looped' electricity supply and had to have it 'delooped'

A similar system which may have similar results is when house mains are fed, usually from an overhead pole, to one of a group of houses and then the supply is daisy chained from junction boxes near the eaves to one or more further houses. This still means that two or more houses are fed from a standard overhead supply cable at low voltage. Although you cannot detect this from either house's supply cabinet.

I checked my daughter's yesterday, first on the loop and a 100 amp fuse after the loop out.

Incoming at (6 inch below) ground level to the cellar, split / meter on the front wall, about 4 feet down and 5 feet from wall to the neighbour. So the outgoing cable is roughly the same length as the distance from the footway, but does not have a massive metal sheath.

Unfortunately the fuse holder are often labelled with the maximum rated fuse rather than what is actually in it so it may not actually be a 100 amp fuse.

Tim

I think nowadays the practice is to put a sticky label on top with the rating of the actual fuse inside. If the rating is embossed or printed on the fuse carrier, that's the maximum rating of the carrier not the rating of the fuse.

Theo

In our case a sticky label on top, torn where the carrier would be opened.

Is this not the principle used in tenement flats? Eight flats. Three phase supply enters at ground floor level. Phase A goes to three flats, phase B goes to three flats and phase C goes to two flats. Next door A goes to two flats, B to three flats and C to three flats and on it goes, to balance the load. This could lead to the curiosity of three flats having a power cut and five remaining on supply.

Splitting up three phase to three successive properties each receiving a single phase is standard. The difference between normal and looped is that normally you run a 3 phase 'trunk' down the street, and each property is an an individual 'branch' off the trunk. In looped, a branch serves two properties.

The important difference is that the 'branch' is a smaller gauge cable than the 'trunk' which means each property is allowed roughly half the current of a normal branch with a single property.

In your flats example, the three phase riser might be sized to be a 'trunk' in which case there's no problem with individual branches to each flat. If the three phase riser then has branches that feed multiple flats, that's potentially more of a problem. However in flats you often don't have such high electricity demands as houses so perhaps a lower supply might be sufficient.

Theo

I think you are on to something. Before I moved, Scottish Power Energy Networks (using contractors) replaced all the cabling because it did not meet (excuse the pun) current standards.