3 phase head in a single phase meter Uk energy networks saying I'm not 3 phase

[kensington]

Hello all I have just purchased a 1970 Bungalow which is directly behind the main area sub station owned by Uk Energy Networks. My property has a 3phase head old brown bakerlite one I called up Uk energy networks who confirm that the property is indeed serviced by a 3 phase supply. I want the head cable moved from the kitchen into the garage about less than ten meters away and I also want 3 phase supply so finding out that the property had a 3 phase supply was a bonus .... however when the Uk Energy technician came and visited the property last week he did not test the head but remakes that its not necessary a 3 phase supply and that it was normal in the 70s to install a 3 phase head really??? he got out out the iPad and said the supply cable is bunched ???? and that a new 40 meter cable and I have to dig the trench would cost 3k.. my electrician has confirmed that all 4 fuses which say 100amp each are all live and 400v are on the head.. Are Uk energy trying to pull a fast one or can someone explain the bunched to me

regards
Mike
I have attached the pic of the mains head

 

[amckay]

I can't really help you on the terminology but couldn't you just put in a 3 phase submain into your garage? Would be a whole lot cheaper.
Then get your meter moved into the new position.
I'd wait to see what another more experienced member comes up with first.

 

[Lucien Nunes]

The characteristics of the supply are given at the consumers terminals downstream of the meter. There might well be three phases at the head but it's immaterial at the moment because they are contracted to supply you with single-phase service. It's up to them whether they are prepared to convert to supply 3-phase, potentially at your cost, or drop the other phases when relocating your meter.

 

[kensington]

Just does not make sense I get the feeling I'm being charged for something i have already got

 

[kensington]

So I have just had it independently tested and its confirmed that it is a 3 phase supply and each wire is pulling 100amp
so don't trust the visit from a uk energy technician. I will be filling a complaint to ofgem and the energy minister Amber Rudd
Having a cable just moved is just £900 not the £2300 quoted to lay a new cable when its already there

 

[snowhead]

They wont want to move and re-terminate a 45 year old cable and then guarantee it's good for another 50 or 100 years.

They can't pull it out the head live and move and re-terminate, it would have to be cut off outside.
Once they've cut it off they wouldn't reconnect an old piece of cable then terminate that into a new head.

You'd be the first to complain if the cable failed after a couple of years and the driveway had to be dug up.

Bunched; page 14, 7.3,

https://library.ukpowernetworks.co....ts/EDS+08-0136+LV+Network+Design+Standard.pdf

 

[Risteard]

How could the other phases possibly be pulling anything let alone 100A if you have no connection to them?

And I presume they have a right to charge for an upgrade to a three-phase service if they weren't contracted to supply one even if it is readily available.

 

[topquark]

Can't see how it can be a bunched supply if your spark got 400V+ between all phases.

 

[kensington]

All I know is that each cable in the head is testing live at 100 amp each including the ones not used the head is a phase head the cable coming into the property is 3 phase so why i am told its not buy that technician,

 

[snowhead]

I will be filling a complaint to ofgem and the energy minister Amber Rudd
Having a cable just moved is just £900 not the £2300 quoted to lay a new cable when its already there

Have you had a written quote or was the price just verbal?

Filing a complaint at this stage seems a bit over the top.
Have you contacted UKPN for an explanation?

 

[Pete999]

Just does not make sense I get the feeling I'm being charged for something i have already got

Looking at the photo, you are supplied with 230v single phase, how are you being charged for something you don't have, can't see the logic in that statement.

 

[Darkwood]

So I have just had it independently tested and its confirmed that it is a 3 phase supply and each wire is pulling 100amp
so don't trust the visit from a uk energy technician. I will be filling a complaint to ofgem and the energy minister Amber Rudd
Having a cable just moved is just £900 not the £2300 quoted to lay a new cable when its already there

How have you had this confirmed and who did it?... it is a criminal offense to open/access the cutout without exclusive permision from the DNO and they don't do that as a rule for obvious safety reasons, to go in full steam saying you have had it confirmed and tested could land you in trouble.
The supply may be 3ph as you suggest but that does not mean the network has the capacity to give you the availability of the other 2 phases, it would depend on the alloted KVA allowance of all the transformer loads so regardless of it been there physically has no bearing on whether it is available for use. You may need a need cable running to an alternative supply.
I have worked with the DNO often and they are well regulated, it is unlikely they are trying to pull a fast one, you can ask for a second opinion but if you feel its been incorrectly assessed but I would be surprised tbh if it had.
I would in your position ask them what they mean when they say the cable is bunched, its possible it might be in a grouped joint in the road and not possible to re-use the existing but I also am not familiar with the terminology they used here, all I can say is if you do go in all bells ringing and steam pooring from your ears they will simply deny your request and you will be stuck with your existing supply.

 

[HappyHippyDad]

They wont want to move and re-terminate a 45 year old cable and then guarantee it's good for another 50 or 100 years.

They can't pull it out the head live and move and re-terminate, it would have to be cut off outside.
Once they've cut it off they wouldn't reconnect an old piece of cable then terminate that into a new head.

You'd be the first to complain if the cable failed after a couple of years and the driveway had to be dug up.

Bunched; page 14, 7.3,

https://library.ukpowernetworks.co....ts/EDS+08-0136+LV+Network+Design+Standard.pdf

I have just watched the DNO removing the cable live from the head, then cutting it live. They then tape it up, pull it through the house wall to the outside. Next they cut it to size (live), tape it up again and terminate it into a new head (all done live). This is my first experience of watching this so I cant say whether or not this is the norm, but I'd be surprised if this was the first time they had done it that way!

 

[Clive P]

Hi,

My take on this is, and I could be completely wrong. Bunching may be the cables are joined together to basically provide a single phase supply ( x3 ) at the head. Did the Electrician measure across the incoming phases or just check there was a voltage at each one. Could be all the same phase?

Regards.

 

[kensington]

The sparky tested all cables at the head each measuring 100 amp each none of them are looped reading 400v

 

[kensington]

he measured across and just to be clear again the supply cable is a 3 phase one the main head is a 3 phase head the feeds are all live at 100amp each 400v but for some reason keep being told its a single phase even the quote states to disconnect a single phase to upgrade to a 3 phase supply EVEN I HAVE 3 PHASE HERE... the only single phase thing is the meter

 

[7029 dave]

But it got R Y B on the head, between phase's should get in excess of400v

 

[Pete999]

So I have just had it independently tested and its confirmed that it is a 3 phase supply and each wire is pulling 100amp
so don't trust the visit from a uk energy technician. I will be filling a complaint to ofgem and the energy minister Amber Rudd
Having a cable just moved is just £900 not the £2300 quoted to lay a new cable when its already there

How on earth can each wire be pulling 100 Amps when there is only one fuse in use

 

[Guest77]

Hello all I have just purchased a 1970 Bungalow which is directly behind the main area sub station owned by Uk Energy Networks. My property has a 3phase head old brown bakerlite one I called up Uk energy networks who confirm that the property is indeed serviced by a 3 phase supply. I want the head cable moved from the kitchen into the garage about less than ten meters away and I also want 3 phase supply so finding out that the property had a 3 phase supply was a bonus .... however when the Uk Energy technician came and visited the property last week he did not test the head but remakes that its not necessary a 3 phase supply and that it was normal in the 70s to install a 3 phase head really??? he got out out the iPad and said the supply cable is bunched ???? and that a new 40 meter cable and I have to dig the trench would cost 3k.. my electrician has confirmed that all 4 fuses which say 100amp each are all live and 400v are on the head.. Are Uk energy trying to pull a fast one or can someone explain the bunched to me

regards
Mike
I have attached the pic of the mains head

Looks like a 3 phase cut out but only single phase in supply, the neutral is connected to the yellow phase end rather than the other end which is marked black, this tells me the cut out was altered to single phase some time ago, probably when a new meter was fitted.

 

[HappyHippyDad]

How on earth can each wire be pulling 100 Amps when there is only one fuse in use

I was wondering that pete. I'm thinking the cutouts have been removed and it has been seen that a 100A fuse is in each of them and that perhaps it is just the language that kensington is getting a little confused with. I have no experience with 3 phase but if each phase is testing at 400V (although again this value does seem unlikely, you would expect it to be a little more) does this not mean it is a 3 phase supply?

 

[Lucien Nunes]

This sounds like a storm in a teacup. YOU don't have a 3 phase supply because YOU don't own the head, the DNO does. It's up to the them what they can supply you with, as Darkwood says even if all three phases are present there might be other single-phase consumers using all the available capacity on the ones you aren't.

Your description of the test 'The sparky tested all cables at the head each measuring 100 amp each' does not make sense electrically, so you might have confused the results. In any case that test involves tampering with equipment that is not yours and is possibly an offence to gain access inside.

If your supply is taken from an older network, there are various possibilities as to why what might first appear as a 3-phase service cable is actually not. Hence, possibly, the mismatch between your neutral connection and the phase markers.

 

[Risteard]

How on earth can each wire be pulling 100 Amps when there is only one fuse in use

Exactly what I was asking earlier!

 

[Risteard]

testing at 400V (although again this value does seem unlikely, you would expect it to be a little more)

Nothing unlikely about it at all as throughout CENELEC countries this is known as a 400/230V supply, so 400v is the correct designation of that voltage.

 

[Darkwood]

he measured across and just to be clear again the supply cable is a 3 phase one the main head is a 3 phase head the feeds are all live at 100amp each 400v but for some reason keep being told its a single phase even the quote states to disconnect a single phase to upgrade to a 3 phase supply EVEN I HAVE 3 PHASE HERE... the only single phase thing is the meter

The link Snowhead kindly provided explains what a bunched cable is, it clearly states that it has to be replaced because it is a bunched cable, basically the spare cores have been used to double up the cores in use to possible reduce the overall resistance.
Quoted from the link:-

Any alterations to networks including bunched conductor installations shall make provision for the restoration of a conventional network solution.

Their own regulation means it has to be replaced

I too don't understand what you say your electrician is confirming, like has been said it is very confusing from an electrical point of view, your pic shows the cutout is sealed so he has no way of testing with meters what you have in there, regardless of it been a 3ph head, I don't think you are in anyway been over charged or having work done that isn't neccessary and going at them with little subject knowledge is only going to create waves and cause you delays and problems, that's if they don't just turn around and say forget it then.

 

[snowhead]

A potential cost saving idea might be to ask your energy supplier, not UKPN for a 3 phase meter, which you'll have to have anyway and Customer side 3 phase isolator.

Before they install it they'll have to confirm with UKPN that the supply is 3 phase and can be used.

Once the meter is in, assuming it can be, apply to UKPN to have the supply relocated.

 

[HappyHippyDad]

Nothing unlikely about it at all as throughout CENELEC countries this is known as a 400/230V supply, so 400v is the correct designation of that voltage.

I realise its the 'correct' voltage, but how often do you measure a single phase supply and it is 230? It is usually more as we seem to be a 230V country on paper only, so i am assuming most 3 phase supplies are still 415V.

 

[Risteard]

I realise its the 'correct' voltage, but how often do you measure a single phase supply and it is 230?

Actually here, frequently. It has always been 230V here as the south was traditionally 220V and Britain traditionally 240V.

Regardless, 400V and 230V are the only correct way to describe those voltages. It is a nominal voltage - voltage fluctuates all the time. So as long as it is within the range of +10%/-6% then that is what it is.

 

[davesparks]

Nothing unlikely about it at all as throughout CENELEC countries this is known as a 400/230V supply, so 400v is the correct designation of that voltage.

Be has stated that the voltage was measured as being 400V, also that he is within a few metres of the substation. The voltage should be a lot nearer 433 as all uk distribution transformers output 250/433 regardless of what the nominal is.

If it was measured at 400 then it suggests the substation is running at its max capacity already

 

[Risteard]

Be has stated that the voltage was measured as being 400V

But that is how the voltage measured would be described.

I wouldn't say I had measured 233V at a terminal - I would say I had measured 230V. Likewise, I wouldn't say I had measured 408V - I would say 400V.

 

[davesparks]

But that is how the voltage measured would be described.

I wouldn't say I had measured 233V at a terminal - I would say I had measured 230V. Likewise, I wouldn't say I had measured 408V - I would say 400V.

Then that would be untruthful and incorrect. A measured value is exactly that, the value which has been measured. It is different to the nominal value which is the theoretical or named value.

 

[davesparks]

I realise its the 'correct' voltage, but how often do you measure a single phase supply and it is 230? It is usually more as we seem to be a 230V country on paper only, so i am assuming most 3 phase supplies are still 415V.

It is not correct, it is nominal, that is to say it is the voltage which has been named as the theoretical value.
The actual voltage which all public network distribution transformers in the UK output is 250/433V, this is a material fact which will not change.

 

[Risteard]

Then that would be untruthful and incorrect. A measured value is exactly that, the value which has been measured. It is different to the nominal value which is the theoretical or named value.

No, because the voltage must be recorded as the nominal value. So by measuring 400V that is anywhere between +10% to -6%. It is still 400V and should be described as such.

The measurement is merely to confirm that there is 400V there, and not to see whereabouts it is within the accepted tolerance for that nominal voltage.

Meters have an accuracy within a certain percentage too so who is to say how accurate your reading is?

 

[davesparks]

No, because the voltage must be recorded as the nominal value. So by measuring 400V that is anywhere between +10% to -6%. It is still 400V and should be described as such.

The measurement is merely to confirm that there is 400V there, and not to see whereabouts it is within the accepted tolerance for that nominal voltage.

Meters have an accuracy within a certain percentage too so who is to say how accurate your reading is?

That is a ridiculously blinkered approach.
This is supposed to be a technical trade and electricians should be able to understand the basic scientific principles behind it.
If you are reporting a measured value then it must be the value which was measured, if you are reporting a nominal value then it should be the nominal value.

 

[Risteard]

That is a ridiculously blinkered approach.
This is supposed to be a technical trade and electricians should be able to understand the basic scientific principles behind it.
If you are reporting a measured value then it must be the value which was measured, if you are reporting a nominal value then it should be the nominal value.

All he asked for someone to check was whether he had a three-phase supply, i.e. 400V between phases.

Why on earth would it be relevant what the precise meter reading is (and notwithstanding the fact that a meter reading has an inherent inaccuracy anyway)?