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

I'd never heard of this before but it is a real thing; it strikes me as a sloppy practice.

Me neither. Hence posting for peoples views :)

I'm in a detached house and have a looped supply, only a 50A fuse. I don't know where the loop goes to, or its routing. I blame teh cheapskate builder wit ha green helicopter. I hate PME and would like to convert to TT but don't know where it is safe to drive an earth electrode in.

It’s not that uncommon by any means. If you follow any EV charger groups it’s a subject that comes up very regularly. Usually de-looping is done at no cost to the homeowner by the DNO on request.

Tim

I am looped with a neighbour (main supply comes up the unadopted lane, along my driveway, into my garage, and there's a loop off to the neighbour's adjoining garage). I only discovered this when I was looking at getting a home charging point (got a plug in hybrid car). It was going to be very costly anyway (I live up an unadopted lane and the lane was going to have to be dug up with all the issues connected to that, e.g. whose cost and what permissions etc), it would have required alterations in the house (primarily the electric shower pulling too much), getting permission from the grid, and all sorts of other things. Also quite a lot of digging of lane and driveway etc ("they'll make good....": Yeah right). I did some sums and some headscratching and didn't pursue it. The car is a PHEV, needs 10kw at most, which I can get in 5 hours cheap overnight on Octopus) on a granny charger occassionally, so I left it at that. I think in a few years, it'll all need redoing if me or the neighbour want solar or groundsource or something else, so I'll bite the bullet then, and hopefully it'll be easier to do, or I may not even be in the property. So I basically kicked the problem down the road.

Looped supplies are very common... where I used to live the supply was overhead and they typically took one aerial supply to the eves of one property, and then looped it (at eves level) to the adjacent but not semi detached property. (which also meant that two halves of each semi were probably on different phases)

Not usually a problem unless you need significant extra capacity in one property (either for consumption or for export) - the looping connection itself is not a factor - just the shared supply cable capacity.

EDF had to dig a trench across the road on the estate near me to provide a new dedicated supply to a looped house.

Original builders (and SEEboard) only ran the main cable down one side of the curved road, on the longer side, and only fitted street lamps on the longer side. Not sure if the position of the street lamps dictated the run of the main cable but further along where the road is straighter, street lamps are on both sides, and so are the main electric cables.

Each pair of houses on the shorter side shared one cable coming under the road. This was fine for the early 70's, all houses had had gas central heating, so no need for heavy duty supply.

According to my DNO, 3 consecutive neighbours share a "3 phase looped supply"

apparently a 3 phase & neutral cable goes to the next door neighbour's meter cupboard.

The 2nd phase plus neutral then goes from her meter cupboard to my house across our two driveways and front gardens.

the 3rd phase + Neutral then goes to her neighbour on the other side to her across their two driveways and front gardens.

We all have 60A supplies each.

This was all done in 1985.

Apparently we can all upgrade to 80A cut outs but if we wish to have a

I also seem to recall that its bad practice to leave de-energised cables underground so I would imagine that if we were de-looped, they would need to remove the 2 looping cables and dig three new trenches for us all to have independent 100A supplies from the main street cable.

If you are all maxing out to 100A then the neutral current will be zero. More likely the combined heating effect of 100A on all three phases.

The developer would have put the street lamps where the local authority said.

Nearly, the neutral is carrying the maximum current when one or two phases are fully loaded and the other(s) drawing little power. If the other phase increases its load, the neutral current is reduced. If all three phases are drawing the same power ('balanced'), the neutral carries nothing.

Permanently balanced three-phase machinery, such as individual motors, may not have a neutral conductor. Without neutral, the connection can be a delta type, the alternative star configuration can be used with or without neutral.

One assumes in this case, the neutral could handle the current for one or two phases of 80A but not of 100A.

Leaving aside cases with reactive loads, can the neutral current ever be greater than one of the phase currents?

Eg if all on one phase, neutral = that phase. If on just 2 phases, currents add vectorwise at 120 degrees, so always less or equal to any one of them. If on all 3 phases, then net current can be as low as zero.

??

nib

Wouldn't the developer draw up the plans with what they wanted to do, and the LA could then negotiate if they were not happy?

Looking at recent developments near me, they seem to have the bare minimum of street lights, with large areas of essentially "private" access, provided with only little lighting bollards - upkeep and maintenance down to the occupiers.

I wouldn't be happy living there.

Chris

I don't believe there is a streetlamp anywhere within 5 miles of me. I am very happy living here.

Non-linear loads can cause problems because the third harmonic adds up in phase in the neutral conductor. John

SEEboard installed the main power cables, not the developer though.

Same developer also agreed a tree-planting schedule along all the verges and on the green spaces, but didn't bother. Also got rid of all the subsoil dug out of foundations to level all the front and rear gardens and just turfed right on top of it, and in one case left an 8*4 sheet of plywood on the top of the 'leveled' ground and just unrolled turf right over it.

The GPO did some odd things with ducting runs such that houses on one side can have FTTP (being close to the duct *) while on the other side FTTP is "not available just yet".

• Trooli have just dug a trench from the middle of the pavement where the duct is, across the front lawn and into the porch of an adjacent house across the road. They ran a purple conduit about 20mm in diameter from ?pavement to porch and rodded in a pull-cable back to the nearest Openreach chamber about 20 metres away. Not sure how they join the thinner purple conduit to the 1970's GPO conduit, unless they pulled the purple conduit inside the Openreach conduit all the way back to the chamber.

If your supply is underground, then how do you tell if it is looped? Or is it only overhead supplies that this applies to?

Cheers

Dave R

It was normal practice on new housing developments for the Supply Board /company to install looped services between adjacent properties from the

Now with Heatpumps and EV's the Network Operators are having to upgrade for the increased requirments sometime to 3 phase supplies.

Looped services apply to underground supplies as well as overheads.

One way to indicate if you have a looped service is to look at your supply point ( usually in a meter box) If the are 2 incoming cables (one in one out) then you don't have a looped service. However this method is not foolproof but only a quick indicator. The only sure way to know is to call your network operator who should be able to tell you.