Electricians - Single to three phase

[john999boy]

1 hour ago, KenONeill said:

And just how much lower does your supply get than "off"?

I think you're missing the point.

As @fabdavrav mentioned (but didn't link to the elusive pages 62 & 63), certain electrical 'appliances' have the capability to demand less power depending upon external factors. 

Removing the power completely isn't really a productive way of load limiting is it?

Edited 4 November, 2021 by john999boy
Typo

[fabdavrav]

2 minutes ago, john999boy said:

I think you're missing the point.

As @fabdavrav mentioned (but didn't link to the elusive pages 62 & 63), certain electrical 'appliances' have the capability to demand less power depending upon external factors. 

Removing the power completely isn't really a productive way of load limiting is it?

 

🤦‍♂️

 

edited & added back to the post

[KenONeill]

23 minutes ago, john999boy said:

Removing the power completely isn't really a productive way of load limiting is it?

It is super effective though.  

[PetrolDave]

2 hours ago, fabdavrav said:

so in the dead of winter on a windless day your ... heat pump may be ramped down...

Great, so when you need warmth most it will be turned down or even off.

 

I suppose that's one way to reduce the state pension bill, give them pneumonia

[cheezemonkhai]

On 03/11/2021 at 21:20, fabdavrav said:

415Volt? in a House & all the industrial plugs & sockets?...won't be allowed...you'd have to go for a split distribution board & phasing down to single core 230v...

 

Your best option is to get additional single cores supplied to the house, one for the car only & one for the heat pump...

 

For example the cable down the street is three core (red, yellow, blue) & neutral. You existing house is supplied with say the red & neutral giving you 230volt, & is limited to 100A. What you need is the yellow core & neutral supplied at 100A for the car & the blue core & neutral supplied at 100A for heat pump....all at 230v single phase.

 

BTW the cables down the street cannot cope with supplying all the 100A to even one third or half of the houses that are on that branch due to the derating of the cables.....This is why the additional loads of electric cars & heat pumps will overload the existing infrastructure & substations....more cables will have to be put in down the streets, or they have to cut/ramp down peoples demands...why do you think they want to fit newer smart meters so they can ramp your demand down??

 

 

No, there's definately no issue and it is allowed, DNO is happy to do it and just awaiting the quote.

They basically supply all three phases to the house, then go to a three phase meter.

 

Any single live to neutral = single phase 230v

Differential on live to live would be reserved for car charger and heat pump.

 

Yes I'd need to deal with 3 fuses in, a three phase meter and a distribution board change, but it's actually faily common these days.

 

 

 

Smart meter wise I think there is some confusion.

 

The incoming smart meter can switch on/off.

Smart controllers for car chargers can apply load capping (eg 22kW might drop to 7 or 3.5 or even pause for example)

Smart heating controllers can run the heat pump at a lower speed.

 

I imagine at some point, the 100A single phase in the UK will become more like an 60 or 80A  three phase delivered to each house.

As for maximum load, of course, but that's why it's in the cost calculations for infrastructure when they provide the quote.

 

Luckily on the building plans for the estate and  can see a pair of dangling phases which are the correct to compliment the one we have, so that at least gives a bit of hope.

Edited 5 November, 2021 by cheezemonkhai

[fabdavrav]

1 hour ago, cheezemonkhai said:

 

No, there's definately no issue and it is allowed, DNO is happy to do it and just awaiting the quote.

 

I said 415Volt in the house is not allowed...you are NOT getting 415Volt in your house & NOT at your sockets...

 

1 hour ago, cheezemonkhai said:

They basically supply all three phases to the house, then go to a three phase meter.

 

Any single live to neutral = single phase 230v

 

As I previously stated:- "you'd have to go for a split distribution board & phasing down to single core 230v..."

 

1 hour ago, cheezemonkhai said:

Differential on live to live would be reserved for car charger and heat pump.

 

As I said:- "You existing house is supplied with say the red & neutral giving you 230volt, & is limited to 100A. What you need is the yellow core & neutral supplied at 100A for the car & the blue core & neutral supplied at 100A for heat pump....all at 230v single phase."

 

1 hour ago, cheezemonkhai said:

 

Smart meter wise I think there is some confusion.

 

The incoming smart meter can switch on/off.

Smart controllers for car chargers can apply load capping (eg 22kW might drop to 7 or 3.5 or even pause for example)

Smart heating controllers can run the heat pump at a lower speed.

 

Why do you think they want everybody to have Smart meters??...the infrastructure cannot cope with the newer additional loads, the cables in the ground & the substations cannot cope with the addition Amperage. They need to be able to turn off your car & heat pump...or at least be able to reduce it to its lowest consumption setting...

 

[fabdavrav]

Here's a little eye opener for you all, as to why the headlong rush to electric everything is stupid, & why everybody must have smart meters:-

 

Dug out a copy of a network drawing I did when I worked at the Hydro Board.

 

Basically, for a normal housing estate of bungalows & two-story houses, each main feeder cable out of the local substation will supply on average 30 houses. Each substation on average around the estate has 4 feeder cables, from it so 4x30 = 120 houses from each substation. This was the normal design for the "average" estate.

 

The feeder cables usually start off as 4 core 185mm CSA, SWA (armoured), XLPE insulation, copper (L1, L1, L3, & neutral, now coloured as Brown, Black, Grey with Blue as the Neutral), & then as they get further away from the substation & after houses have been connected, they go down to 95mm CSA & 70mm CSA.

 

The max rated current capacity for these cables buried in the ground (BS7671) as 3 phase AC is:-

185mm = 460Amp

95mm = 315Amp

70mm = 265Amp

 

For a rough & ready calculation to single phase & current supply:-

400 x 460 = 184,000Watts (184kW) at 400Volts 3 phase

184,000 / 3 = 61,333Watts (61.33kW) per single phase at 230Volts

61,333 / 230 = 266.66Amps per single phase at 230Volts

Therefore, each Line (phase) of the 4 core 185mm cable can supply 266.6Amps at 230Volts = 61.33kW

 

The 30 houses will be distributed evenly across the above cable's 3 Line cores, so that’s 10 houses per phase/core. Evenly split between the 10 houses is 26.6Amps or 6,118Watts (6.1kW) per house. Just because your fuse board has a 100Amp main incomer fuse/breaker, doesn’t mean that you can use ALL 100Amps (23kW). Well, you might be able to & one of your neighbours might, but that only leaves 66.6amps (15.31kW) for the other 8 houses on your Line (phase).

 

Now you want to add the following loads to every home:-

 

Most heat pumps (for single phase 230Volt) are in the range of 4kW to 14kW of electricity consumption.

 

Electric car AC charges being:-

3.7kW (16Amp) 230Volt

7.4kW (32Amp) 230Volt

11kW (32Amp) 400Volt (3 phase)

22kW (64Amp) 400Volt (3 phase)

43kW (120Amp) 400Volt (3 phase)

 

Lets say each of the 10 houses has a 4kW heat pump, or a big one but its just using 4kW, plus a basic 7.4kW car charger, that’s (4kW + 7.4kW) x 10 = 114kW additional load onto a Line (phase) that can only cope with a max of 61.33kW.

 

The electricity supply is designed to be derated as they don’t expect every home to have every appliance on 24/7. However, with the new additional heavy loads such as electric car charging & heat pumps, the existing infrastructure (cables/substations/etc.) cannot supply the demand. This is why they are fitting “smart” meters so that they can control the demand from the big heavy loads e.g. electric car charging & heat pumps, & these WILL be switched off & timed etc..

 

Welcome to the future…power cuts & “brown outs”.

 

 

 

Edited 5 November, 2021 by fabdavrav
clarity

[KenONeill]

36 minutes ago, fabdavrav said:

Welcome to the future…power cuts & “brown outs”.

So if I'm reading this correctly, your shower at, say, #26 could suddenly go from hot to Baltic because #20 and #32 both plugged their EVs in to charge?

[Ootohere]

We need to expect that as new developments are developed and built that they are fit for this day and age and into the future.

Properly insulated, and with the systems needed for peoples needs for utilities and transport.

 

It is not like the Energy Providers, Planners & Developers are unaware of the requirements and timeline.

 

https://www.insider.co.uk/news/500-million-perth-west-development-24231488

 

 

https://www.scotsman.com/business/aviva-opens-solar-power-carport-in-perth-that-can-power-500-homes-3036604

 

 

Edited 5 November, 2021 by roottoot

[fabdavrav]

28 minutes ago, KenONeill said:

So if I'm reading this correctly, your shower at, say, #26 could suddenly go from hot to Baltic because #20 and #32 both plugged their EVs in to charge?

 

That's if they are on the same Line/phase as you are.

 

Simply put the existing cables in the ground cope with a max of 266.6Amps at 230Volts = 61.33kW on each Line/phase. This to be shared between 10 houses.

 

With the ADDITIONAL loads of a 4kW heat pump, & a basic 7.4kW car charger, to every house...that's an  additional load of 114kW onto each Line (phase)!

 

So they have to "derate" somehow....smart meters to ramp down your demands from the car & heat pump...should be fun in winter when we get high pressure weather (no wind)...

 

Even with LED lighting & "A" rated appliances you still cannot get away from the facts the infrastructure isn't designed for the new high kW loads. Expect to see electricity costs go through the roof as a means for the companies to be able to afford to double up the cables in the ground & increase the capacity of the substations.

Edited 5 November, 2021 by fabdavrav

[KenONeill]

17 minutes ago, fabdavrav said:

.smart meters to ramp down your demands from the car & heat pump...should be fun in winter when we get high pressure weather (no wind)

Yeah, got all this and I picked 20, 26 and 32 as being every third house on the same side of the road.

 

Also, FWIW I've been arguing about the uselessness of wind power in a calm or a storm, and solar in a Scottish Winter for years.

Edited 5 November, 2021 by KenONeill

[Ootohere]

@KenONeill

You have been very much arguing how useless and you are still.

Those that are spending the money are not paying attention to you and just doing their own thing.  Go figure!

 

The Wind Turbines are going higher and further offshore so as less becalming.

The Solar is going in and the Hydro is still there.

The South of the UK is still needing more Nuclear and they will share that when Scotland needs it as they are getting renewables when surplus to Scotland which it is very often.

 

https://www.pressandjournal.co.uk/fp/business/local/1401755/housebuilder-plugs-in-new-electric-car-chargers/

 

The time is now for all the new employment of skilled people doing skilled jobs and sorting out the kind of crappy infrastucture that can be updated.

 

The roads get dug up all the time anyway Time they get all dug up again. .   

Houses get demolished and others renovated and modernised over time.   The stuff about insulating homes has been going for over 50 years and some houses have been done time after time and are still in need of being properly modernised.  

 

 

 

 

 

 

 

 

Edited 5 November, 2021 by roottoot

[fabdavrav]

25 minutes ago, KenONeill said:

Yeah, got all this and I picked 20, 26 and 32 as being every third house on the same side of the road.

 

Also, FWIW I've been arguing about the uselessness of wind power in a calm or a storm, and solar in a Scottish Winter for years.

 

The reason (joke in my mind) that they keep plugging wind power up here is that the companies get paid more to stop the turbines in very windy conditions as the grid CANNOT distribute the surplus down south when the demand up here has already been met.

 

£76million has already been paid out this year:-

 

Electricity customers paid windfarms £1bn to switch off turbines - STV News

 

There was a local paper which had the BOWL wind farm (Moray Firth) being paid a six figure sum in the space of a few days to shut off.

 

 

Total clusterfeck.....

Edited 5 November, 2021 by fabdavrav

[Ootohere]

So when the electricity that can be produced as easily as it is and stored it will be a very different matter.

At present the National Grid has the contracts to get what they get from across the English Channel and say that the wind was not blowing or blowing too hard and turbines were off.

The Kidology is unbelievable. 

  But the electricity will go to make hydrogen and the Oil & Gas companies are now part of the future of using the renewables.

 

Plenty are doing OK from Wind Farms but eventually Baron Nichol Stephen and Sam Cams family and other land owners will just have memories of the money they made early on and obviously they will still have the money.They might even get scrappage payments as their turbines are decommissioned.

 

There are more Farmers now that are Energy Companies than there are actual working only as farmers for food or growing renewables.

[fabdavrav]

39 minutes ago, KenONeill said:

Yeah, got all this and I picked 20, 26 and 32 as being every third house on the same side of the road.

 

 

Doesn't work like that....

 

In theory if a straight street has the numbers 1-30 on it (evens one side, odds the other side) the 4core 3phase cable will be split as follows:-

 

Line/core 1:- 1, 4, 7, 10, 13, 16, 19, 22, 25, 28

Line/core 2:- 2, 5, 8, 11, 14, 17, 20, 23, 26, 29

Line/core 3:- 3, 6, 9, 12, 15, 18, 21, 24, 27, 30

 

However it can be common to have neighbouring properties on the same phase/core...so long as the total load on each core is similar, & fairly well distributed down the length of the cable.

Edited 5 November, 2021 by fabdavrav

[cheezemonkhai]

16 hours ago, fabdavrav said:

 

Doesn't work like that....

 

In theory if a straight street has the numbers 1-30 on it (evens one side, odds the other side) the 4core 3phase cable will be split as follows:-

 

Line/core 1:- 1, 4, 7, 10, 13, 16, 19, 22, 25, 28

Line/core 2:- 2, 5, 8, 11, 14, 17, 20, 23, 26, 29

Line/core 3:- 3, 6, 9, 12, 15, 18, 21, 24, 27, 30

 

However it can be common to have neighbouring properties on the same phase/core...so long as the total load on each core is similar, & fairly well distributed down the length of the cable.

I understand what you’re saying, but no the working include a 3 phase meter, a 3 phase distribution board and probably a commando.

 

Of course the sockets will still be on one phase, because a plus/light does have 3 lives! Doesn’t mean it’s not a three phase supply though does it?

[fabdavrav]

2 hours ago, cheezemonkhai said:

I understand what you’re saying, but no the working include a 3 phase meter, a 3 phase distribution board and probably a commando.

 

Of course the sockets will still be on one phase, because a plus/light does have 3 lives! Doesn’t mean it’s not a three phase supply though does it?

 

You originally said "Has anyone changed from single to three phase at home?"

 

I questioned this with "415Volt in the house with industrial sockets etc."..& stated it wouldn't be allowed...

 

 

For clarity, the mains cables in the road have 3 line cores & one neutral. Take one Line core & the Neutral = 230Volt single phase. Take two Line cores & one Neutral = 400Volt single phase. Take all three Line cores & Neutral = 400Volt three phase.

 

 

You are being supplied with additional cores (lines). Each core/Line is 230Volt single phase & can be arranged so that they have their own separate single phase meters in their cabinet & then split out one to your existing house fuse board, one to the car charger & one to the heat pump.

 

Or they could do as per common practice in commercial/industrial buildings & that is terminate the same cable that's in the ground in the street in their 3 phase 400Volt cabinet with all the relevant meter, fuses etc. Then split off the three cores/lines, & in your case one line/core to your existing house fuse board, one to the car charger & one to the heat pump all as single phase 230Volt

 

 

Using the later industrial setup means only one meter, instead of three....& still means that everything is single phase 230volt that comes out of their cabinet, NOT 400Volt & NOT 3phase!

 

 

However they could take one line/core for the house at 230Volt single phase & then you could take a 400Volt 3 phase for a 43kW 400Volt 3 phase car charger.

 

 

 

Edited 6 November, 2021 by fabdavrav

[cheezemonkhai]

It’s a single meter and a three phase distribution board.  Therefore it’s a 3 phase supply.

 

The 230v item will come from one of l1/2/3 to neutral.

The car charger and heat pump will run on 415v 3 phase.

There will probably be a 3 phase commando type socket hidden out the way.

 

I’m sure there’s some fine detail that means you don’t think that the above is a three phase supply, but I am struggling to see this detail from your post.

[fabdavrav]

6 hours ago, cheezemonkhai said:

It’s a single meter and a three phase distribution board.  Therefore it’s a 3 phase supply.

 

The 230v item will come from one of l1/2/3 to neutral.

The car charger and heat pump will run on 415v 3 phase.

There will probably be a 3 phase commando type socket hidden out the way.

 

I’m sure there’s some fine detail that means you don’t think that the above is a three phase supply, but I am struggling to see this detail from your post.

 

 

Your original statement of "Has anyone changed from single to three phase at home?".....implied you were having 3 phase in the house at the sockets & lights switches....which of course you cannot have as all your existing lights, sockets etc are all 230volt single phase & the appliances require this to run.

 

The rest of what you say is what I was previously stating as one of several possible ways for the electricity lot to split the cable in their box, depending on your car charger requirements...i.e your existing fuse board for all your lights, cooker, sockets etc in the house will remain as 230Volt single phase on one core/line.....the other new cores/lines brought into the suppliers box will be for the heat pump & car charger whether they be single phase or 3 phase as required.

 

I did used to work for the local electric company who also ran the network & knew what they call "Low Volt" (everything from the substations to the home/business) distribution layout requirements very well. 

Edited 6 November, 2021 by fabdavrav

[J.R.]

I have 3 phase into my property and I did all the wiring and distribution, ERDF ran 3 phases and a neutral down from the cable bundle running under my roof to my installation which consists of an external CCCP (coffret collectif de coupure and protection) this has the huge fuses in that ERDF can pull to isolate the building, mine has a second set of fuses for réemergence meaning that if another property were fire damaged or perhaps a digger cut through the supply cable they could spur off my cabinet to feed that building, I say "my cabinet" - I paid for it and installed it but the fuses are ERDF and once they closed the door and added their seal it becomes their domain.

 

From there I ran a 4*95mm2 aluminium cable to the colonne collectif within the building hallway, this is a 3 phase distribution board that carries the ERDF fuses for the 8 electrical meters beside it for my 6 flats, the general building services (lighting & heating of the common areas) and one spare for the final flat which is currently my workshop.

 

Each of the individual meters has a seperate disjoncteur d'abonnement which is a 650ma RCD and current limiting circuit breaker set the supply current for the standing charge paid by each consumer, the more you pay the more current you can have, they are all set to 6kva except my appartment which has storage heaters and is at 9kva the maximum allowable for the cable sizes I ran to each appartment and for the 95mm2 supply cables. I think the limit is 320amps which could be exceeded if all the appartments drew the maximum but it is derated by a foisonnement factor, I think the term in English was "diversity" meaning not every consumer will be drawing the maximum at the same time.

 

All of this and the complete electrical installations in each appartment I was allowed to do as an unqualified individual, I did in fact have the IEE 16th edition certification in the UK but it counted for nothing in France, any individual can do their own electrics but to get a mains connection to the grid it has to be inspected by a government body called CONSUEL and costs about €100 for the very in depth on site inspection, I had to have 7 Consuel inspections as and when the appartments were finished.

Edited 6 November, 2021 by J.R.

[fabdavrav]

18 hours ago, J.R. said:

I have 3 phase into my property and I did all the wiring and distribution, ERDF ran 3 phases and a neutral down from the cable bundle running under my roof to my installation which consists of an external CCCP (coffret collectif de coupure and protection) this has the huge fuses in that ERDF can pull to isolate the building, mine has a second set of fuses for réemergence meaning that if another property were fire damaged or perhaps a digger cut through the supply cable they could spur off my cabinet to feed that building, I say "my cabinet" - I paid for it and installed it but the fuses are ERDF and once they closed the door and added their seal it becomes their domain.

 

From there I ran a 4*95mm2 aluminium cable to the colonne collectif within the building hallway, this is a 3 phase distribution board that carries the ERDF fuses for the 8 electrical meters beside it for my 6 flats, the general building services (lighting & heating of the common areas) and one spare for the final flat which is currently my workshop.

 

Each of the individual meters has a seperate disjoncteur d'abonnement which is a 650ma RCD and current limiting circuit breaker set the supply current for the standing charge paid by each consumer, the more you pay the more current you can have, they are all set to 6kva except my appartment which has storage heaters and is at 9kva the maximum allowable for the cable sizes I ran to each appartment and for the 95mm2 supply cables. I think the limit is 320amps which could be exceeded if all the appartments drew the maximum but it is derated by a foisonnement factor, I think the term in English was "diversity" meaning not every consumer will be drawing the maximum at the same time.

 

All of this and the complete electrical installations in each appartment I was allowed to do as an unqualified individual, I did in fact have the IEE 16th edition certification in the UK but it counted for nothing in France, any individual can do their own electrics but to get a mains connection to the grid it has to be inspected by a government body called CONSUEL and costs about €100 for the very in depth on site inspection, I had to have 7 Consuel inspections as and when the appartments were finished.

 

 

The majority of what you say re the layout is simple distribution & the same practice is carried out here for a building with multiple flats etc...i.e. have a 4 core (incomer) into the main distribution board & then tail out with numerous single phase 230volt cores to individual meters. 

 

Again over here everything upto & including the meter & including the fuses beforehand & the cabinet that encloses everything is "owned" by the electric company (network supplier).

 

 

Having a 4 core incomer to the meter in a single "domestic" home is more common than people think..I've dealt with many examples:-

 

Many older mansions, hunting lodges, in fact homes with more than 8 bedrooms, properties with swimming pools, properties with numerous garages & car collections & the owners have a few Bendpak lifts, properties which operate as a  B&B' in the summer. Owners that are into metalworking/pottery & have a workshop, with ovens, or furnaces, or welding machines.

 

In these cases either extra single cores at 230Volt are taken from the street for the dedicated appliances/workshops/etc. or a 4 core incomer to the meter will be installed. Then a single core 230Volt will be taken to the existing main house fuse board for all the basic lighting, sockets, etc.. Then a dedicated single core 230Volt taken to the workshop, swimming pool pump room, kitchen etc. In some cases there may also be a 400volt 3 phase taken to certain fixed appliances in the same kitchen or pump room , workshop, e.g. ovens, lifts, welders, etc..

 

In big houses without any "industrial" type appliances, the property will be split up floor by floor or wing by wing for each of the 100A single 230Volt cores. 

Edited 7 November, 2021 by fabdavrav
clarity

[Ootohere]

EDIT.

Doh, sorry,

thought i was posting in the 'Wind Power' thread.   Went wrong somehow.

http://briskoda.net/forums/topic/221445-wind-power-to-the-rescue

 

So clever.

2021

 

 

2011

 

 

 

 

Edited 10 November, 2021 by roottoot

[cheezemonkhai]

On 05/11/2021 at 15:08, fabdavrav said:

 

Electric car AC charges being:-

3.7kW (16Amp) 230Volt

7.4kW (32Amp) 230Volt

11kW (32Amp) 400Volt (3 phase)

22kW (64Amp) 400Volt (3 phase)

43kW (120Amp) 400Volt (3 phase)

 

Just on this, when you look at the manufacturers they state:

 

- 11kW = 16A 3 phase

- 22kW=32A 3 phase

 

Your numbers however make sense at 415V I = P/V

 

I'm assuming the chargers are taking multiple single phases in to give the higher charging rate, such as:

- 11kW = 3 * 3.7kW charging (3x16A)

- 22kW = 3 * 7.4kW charging (3x32A).

 

 

Regarding the rest of it, yes I think there are plenty of problems supplying the amount of electric we will all required, although I'm not sure the smart meter itself gives the fine grained control over different appliances suggested. The smart appliances/chargers however certainly could.

 

I imagine (but you definely know more than me) that areas designed for night storage heaters are probably helped by more capacity, although I doubt that'll be anywhere near enough to mean there are not big problems.

 

TBH I expect hydrogen fuel cells to appear in larger vehicles or longer range vehicles given time... but only time will tell how this getting away from fossile fuels will be solved.

 

Edited 22 November, 2021 by cheezemonkhai

[cheezemonkhai]

dbl post

Edited 22 November, 2021 by cheezemonkhai

[fabdavrav]

21 hours ago, cheezemonkhai said:

Just on this, when you look at the manufacturers they state:

 

- 11kW = 16A 3 phase

- 22kW=32A 3 phase

 

Your numbers however make sense at 415V I = P/V

 

I'm assuming the chargers are taking multiple single phases in to give the higher charging rate, such as:

- 11kW = 3 * 3.7kW charging (3x16A)

- 22kW = 3 * 7.4kW charging (3x32A).

 

 

Regarding the rest of it, yes I think there are plenty of problems supplying the amount of electric we will all required, although I'm not sure the smart meter itself gives the fine grained control over different appliances suggested. The smart appliances/chargers however certainly could.

 

I imagine (but you definely know more than me) that areas designed for night storage heaters are probably helped by more capacity, although I doubt that'll be anywhere near enough to mean there are not big problems.

 

TBH I expect hydrogen fuel cells to appear in larger vehicles or longer range vehicles given time... but only time will tell how this getting away from fossile fuels will be solved.
 

 

 

415V is "old"..its 400V.....just like 240V is now 230V..

 

I left out various other complications in the calculations such as power factors etc...basically to keep it simple..

 

As I said before the 4 core incomer has 3 "line" cores & one neutral core..Take one Line core & the Neutral = 230Volt single phase. Take two Line cores & one Neutral = 400Volt single phase. Take all three Line cores & Neutral = 400Volt three phase.

 

Smart meters cannot control your washing machine etc. but they may (doubt it) restrict the kW you are drawing...but they will be used for controlling & restricting car chargers & heat pumps, i.e big loads..so your car may not be fully charged in the morning when you get up in the morning (worst case scenario).

 

 

The old white meter heating is usually just your existing  230v single core incomer split two ways before the meter....much like in flats etc....& will NOT give you what you need for 3phase 400V. 

 

 

Example:- I attach a (bad) photo of a property I own. Single core (red from street) into a two main 100A fuse block. One tail out the downstairs property meter & then into the downstairs fuse board. Another tail out to the meter in the flat (separate address) above. This set up is common in these older buildings, in fact this install was done by the Hydro board in 1999. The white meter heating was split like this in many properties, in fact the downstairs property in this case had white meter heating which is why I ripped it out & had what you see installed in 1999. (fuseboard was later uprated to 17th ed regs) (P.S my incomer is a single core live, the insulated steel wire armour is used as both the neutral & earth as its PME type system actualy called TN-C-S)..

 

On a side note:- In many cases if you were building a new house or renovating, & fitted an electric shower above a certain kW rating you had to get permission from the Hydroboard. I know one of my mates when his parents built a new home in the middle of nowhere (like a lot of places up here), he stated he wanted the pole transformer to be "X" rating, the HB said nope, & gave him a lower rated one...so he basically "ran it hot" so it kept tripping the internal thermal fuses etc....They soon swapped it for the higher rating that he originally asked for. This was for a detached 6 bed house with 3 electric showers & was in 1994. So now try to go back & add electric car charging & heat pumps....basically double the demand!!

 

AS I said before its the whole network which cannot cope, & that for each substation there are usually four main 185mmCSA cables each supplying 30 houses across 3 lines. Each Line (phase) of the 4 core 185mm cable can supply 266.6Amps at 230Volts = 61.33kW...& now you want to add a 4kW heat pump, or a big one but its just using 4kW, plus a basic 7.4kW car charger, that’s (4kW + 7.4kW) x 10 = 114kW additional load onto each Line (phase) that can only cope with a max of 61.33kW.!!

 

You now need to install DOUBLE the capacity in ALL the cables & substations!

 

 

Edited 23 November, 2021 by fabdavrav
clarity