Three phase supply with strange wiring into single phase

[martind]

We bought a house recently and I thought I'd got lucky with a three phase supply that had only one phase connected. I spoke to the DNO (SSEN), who surprised me by saying I should take off the cover of the cut out myself and take a look inside, "but don't touch any wires!".
So that's what I did and don't know what I've found. Clearly I expected one conductor going to each of the fuses, but instead it looks like two of them go into the same fuse and the other is the neutral.
Could this be easily rewired for 3 phase?
It's to accommodate a large solar array and 22kW EV charging.

 

[Fleeting]

I am somewhat surprised they suggested you remove the cover to have a gander. Can this be changed to a three phase supply only they can answer that.

 

[martind]

I suppose what I was looking for is confirmation of what this is. My guess with my (limited) understanding, is that the red and yellow cables are both carrying the same live single phase supply, with the blue cable as neutral. So the incoming cable is potentially one that could be used for a 3 phase supply - likewise with the cutout - but that's all kind of pointless because it's connected to a single phase supply at the substation/transformer.

Is that a possible scenario?

 

[Fleeting]

No way of knowing whether at source there is three phase or single.

 

[Murdoch]

SSEN are happy for competent sparks to remove seals

 

[SPECIAL LOCATION]

In my thickness, (after a few cans of Thatcher's Cider),,,,,

It just looks like a 4 core cable used as 2x Live (Phase), [Red + Yellow]
and 2x Neutral [Blue + Black]..

NO idea how the armour is or isn't connected?
And NO idea how easy or not it is to convert to 3-phase?

I think you will need conversations with other bodies who do not purely exist on internet & social media.

 

[Phoenix]

Either two phases of a three phase system, or both sides of a split phase system, but you'd need to measure the voltage to know, and I would NOT suggest you start sticking test probes into the supply side of a cutout! The DNO should be able to send someone out to establish what is provided

 

[martind]

Thank you for your input. I'll have to get back to the DNO and ask what's going on here. The property was built on a brownfield site in 1986 and they had to get all utilities connected. The double garage where gas / electric comes in was accidentally messed up in 2015 and they had it rebuilt (geriatric driver reversed into it at high speed and pushed the whole thing 500mm backwards, sliding on the DPM), so it could be that they went from 3 phase to single phase / split phase at that point.
In any case, SSEN should be able to find out what's going on.

 

[ProDave]

In my thickness, (after a few cans of Thatcher's Cider),,,,,

It just looks like a 4 core cable used as 2x Live (Phase), [Red + Yellow]
and 2x Neutral [Blue + Black]..

NO idea how the armour is or isn't connected?
And NO idea how easy or not it is to convert to 3-phase?

I think you will need conversations with other bodies who do not purely exist on internet & social media.

I would say that's a 3 core concentric. Red, yellow and blue cores and the black it the wrapped outer core.

to me it looks the be a TNS supply with the outer core as earth, blue as neutral, and red and yellow in parralel as Live. Quite why they fitted a 3 phase head the that is the mystery bit.

The cable probably could be reconfigured at the DNO's discression and assuming 3 phase was available at the other end of this cable, as a 3 phase TNC-S with the outer as the normal TNC-S combined neutral and earth.

If the OP really wants a 3 phase supply to the house, get a quote from your DNO to upgrade to 3 phase, it might be quite cheap if they are happy to repurpose that cable and 3 phase is available close by, or it might be astronomically expensive.