Smart meters, electric vehicle charging points and Economy 7

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you have a switched supply and a permanent supply, see the switch at lower right, left side is permanent and right side of switch is switched via the black box above, with both cu neutrals joined together in the left henley block
 
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Does this help at all with explaining how E7 works. This is a fairly standard installation but there are variations
Blue is neutral
Red is the live wire which is powered 24 hour a day and is expensive during the day, cheap at night. It ends up in your large CU
Orange is the cheap rate live wire controlled power and ends up in your small CU ie is only energised by a contact in the teleswitch
Pale blue is the signal from a contact in the teleswitch to change to the cheap rate part of the meter
The teleswitch includes a radio receiver for a time signal to do the changeover.
1656579597514.png
 
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This is the worrying bit. Because it is PME if the PEN is lost and car parked outside unless some thing is done to auto disconnect the earth some one touching the car can get a shock.

There are a number of ways the EV charging point can get around the problem, a small earth rod to detect loss of PEN, a large earth rod and turn supply into TT, and monitor the voltage and auto disconnect if not in the 207 to 253 volt range. There may be other ways, but it means some thing needs to be done if charged outside, could even be an earthed mat under where the car is parked.

One would assume if the company is paying for the car, they also pay for the fuel, but it seems the main reason for the EV is the tax breaks that come with it. So may be the company will not pay for the charge point. But they are reasonable for the health and safety of their employees, so not sure what is down to them to do?

I remember an electrician being sent home as it was claimed he was drunk, so next day there was an interview, and the question was raised if drunk then the manager could not have sent him home in his own car, so it was claimed he was send home as he felt unwell. Not sure if that would have satisfied HSE, but he did not get sack, as the company is responsible while the employee goes to and from work.

So not sure how they have to deal with EV's? I know some one I work with was given a courtesy car which was an EV, without any charging lead, one way to ensure limited miles put on the clock. But was it because of safety, and not knowing if his supply was safe for use outside?

It is an on going thing EV charging, I tend not to take my charger with me on my EV e-bike, I could I am sure go into Morrisons cafe and plug the battery in while eating my meal, but the battery easy removes from the bike, so taking the battery in doors, and the charger is class II.

I saw the results of an earth mat connected to a PME supply, and the melted 4 mm earth cable, so I don't know what the result will be with EV charging points, and how to make them safe.
 
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.... One interesting thing that I can't get my head round, though. The storage heaters will only warm up at night (if we use them). So if the whole house switches to E7 at night, what prevents the storage heaters from drawing power during the day as well? Their consumer unit must be on some feed that only goes live at night?
It would seem that your 'Radio Teleswith' not only switches the meter between day and night registers at the appropriate times but also contains a 'switch' (relay/contactor) which switches the storage heaters on only during the cheap/night periods. I presume that the isolator (white thing below the teleswitch) contrails (i.e. allows you to switch off) the storage heaters?

Kind Regards, John
 
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As to the lead I showed, if being charged in a garage no problem using the lead in a 32 amp socket, the problem is charging outside, be it a hot tub or an electric car inside no problem with TN-C-S but outside there is.
I'm not sure that it is necessarily as simple as that. For those concerned about lost TN-C-S PENs, I'm not convinced that the inside of my garage would be appreciably 'safer' ('less of a potential problem') than 'outside'

Kind Regards, John
 
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Just posted to my eMail 'box' from the IET.

Government fails to rule out EV tax as new regulations come into force
The government has described claims that new regulations on smart charging for electric vehicles (EVs) lay the groundwork for a new tax on EV charging as “ludicrous”.


However, the government failed to rule out introducing a new tax as a way of replacing almost £30bn of revenue it stands to lose in fossil fuel taxes as petrol and diesel cars are replaced by electric models.
Under The Electric Vehicles (Smart Charge Points) Regulations 2021, that come into force today, all newly fitted EV charge points must have smart functionality.
This will allow for the potential of ‘electricity rationing’ by deciding when EVs can be charged, helping to avoid overloading the National Grid at peak times.
It will also enable EV charger usage to be billed at higher electricity prices than domestic electricity by operating with a dedicated smart meter.
Currently, petrol and diesel drivers pay fuel duty at 52.95 pence per litre, which brought in £28bn for the government last year. Petrol and diesel are also subject to 20 per cent VAT. By contrast, electric car users pay no fuel duty, and VAT on domestic electricity is only charged at 5 per cent.
Motor financing firm MotoNovo said the potential for higher cost EV home-charging tariffs is “sure to be another concern for consumers reeling under record utility price hikes”.
“In the short term, the government may consider that the timing for dedicated EV charging is uncomfortable, having cut fuel duty by five pence per litre recently in a bid to ease the impacts of the increasing cost of living,” said Mark Coles, head of marketing at MotoNovo.


However, he added that the “stark reality is that the revenue generated from fossil-fuel vehicles ... has to be replaced somehow as EV popularity increases”.
In response, a government spokesperson said smart charging would “actually lower costs for most electric vehicle owners” as it would enable vehicle owners to access cheaper vehicle charging during periods when electricity prices are low – for example overnight.
“This is not a tax and the new regulations will actually save people money,” they added.
At the same time, the government said it was committed to striking a difficult balance between ensuring that “motoring tax revenues keep pace with the changes brought about by the switch to electric vehicles, whilst keeping the transition affordable for consumers”.
A day before the new regulations came into force, the government’s independent advisors, the Climate Change Committee (CCC), argued that some form of “road pricing” is needed under which drivers are charged for how much they drive if the government is to cover the “significant hole” in the public finances left by the loss of fuel duty and other taxes when petrol and diesel cars are replaced by electric models.
In its progress report to parliament, published yesterday, the CCC said a “sensible and fair” approach would see the costs covered by drivers, rather than general taxation. Potential approaches, it added, range from “a simple charge per mile driven, which could be levied based on annual odometer checks, to more sophisticated schemes that vary the charge based on the time of day or the location/type of road being used, based on vehicle-tracking technologies.”
The sale of new petrol and diesel cars is set to be banned in 2030 but the CCC said the government needed to explore the policy now so it is ready to be implemented this decade. Introducing a new tax system at an “early stage” will help avoid a situation where drivers “begin to assume that EV driving will always be tax free”, they said.
 
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Just posted to my eMail 'box' from the IET.
It has surely always been inevitable that, sooner or later, the government will have to find a way of 'charging' for EV usage (whether by a 'tax' on EV charging or something like a 'mileage tax'), to compensate for the progressive loss of income from fuel excise duty?

Kind Regards, John
 
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It would seem that your 'Radio Teleswith' not only switches the meter between day and night registers at the appropriate times but also contains a 'switch' (relay/contactor) which switches the storage heaters on only during the cheap/night periods. I presume that the isolator (white thing below the teleswitch) contrails (i.e. allows you to switch off) the storage heaters?

Kind Regards, John
That white thing is a 2 pole isolator which isolates both the 24 hour power and the cheap rate line but not the neutral. Personally I'd have put it between the meter and henley
 
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That white thing is a 2 pole isolator which isolates both the 24 hour power and the cheap rate line but not the neutral. Personally I'd have put it between the meter and henley
Yes, you're right, and it does seem an odd way to have done it - as you say, upstream of the Henley (and DP) would seem more logical. I suspect that the way it's ended up may be a consequence of the order in which things were done (over the years) and what was 'most convenient' at the time!

Kind Regards, John
 
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So if the whole house switches to E7 at night, what prevents the storage heaters from drawing power during the day as well? Their consumer unit must be on some feed that only goes live at night?
That's how ours works. There are two separate consumer units - the normal one and a smaller one that only becomes live during the night. That used to run the storage heaters, but now is useful for running washing machine, dishwasher, dehumidifier, or anything else that can with advantage be run at night on cheaper electricity.
Switching on automatically avoids the need for separate timers, and the master timer in the E7 supply to the consumer unit runs on clockwork which is wound electricly, so has about a week's worth of normal operation so it can weather all normal power cuts. Ordinary plug in timers have to be reset after every power cut, which are frequent in west Wales.

Everything plugged into a socket on the ordinary consumer unit is cheaper at night, only the separate E7 consumer unit switches off during the day.
There are two meters inside the same box - I read them by flicking a button which displays each in turn. There are several other displays too, heaven knows what they mean.

The network of cabling for the previous storage heaters terminates in a separate socket outlet in each room - marked with dymo tape to avoid confusion.
 
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Kia seem to work with two charger installers - PodPoint and BP.
Charge points are not specific to a particular car, you can have one installed from anyone.

Your consumer units are obsolete, and the main one is completely full anyway.
 
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Does this help at all with explaining how E7 works. This is a fairly standard installation but there are variations
Blue is neutral
Red is the live wire which is powered 24 hour a day and is expensive during the day, cheap at night. It ends up in your large CU
Orange is the cheap rate live wire controlled power and ends up in your small CU ie is only energised by a contact in the teleswitch
Pale blue is the signal from a contact in the teleswitch to change to the cheap rate part of the meter
The teleswitch includes a radio receiver for a time signal to do the changeover.
View attachment 273414
Thanks, that's brilliant! Presumably the incoming supply is the heavy black wire at the bottom, left, and then it goes through that big black box with "PME Earth" written on it - which I guess is some kind of master fuse? Then it goes into the small, oblong black box above that (not sure what that is?) and then the oblong white one, before going through the meter, after which, your marked-up drawing takes over?
 
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View attachment 273415 This is the worrying bit. Because it is PME if the PEN is lost and car parked outside unless some thing is done to auto disconnect the earth some one touching the car can get a shock.

There are a number of ways the EV charging point can get around the problem, a small earth rod to detect loss of PEN, a large earth rod and turn supply into TT, and monitor the voltage and auto disconnect if not in the 207 to 253 volt range. There may be other ways, but it means some thing needs to be done if charged outside, could even be an earthed mat under where the car is parked.

One would assume if the company is paying for the car, they also pay for the fuel, but it seems the main reason for the EV is the tax breaks that come with it. So may be the company will not pay for the charge point. But they are reasonable for the health and safety of their employees, so not sure what is down to them to do?

I remember an electrician being sent home as it was claimed he was drunk, so next day there was an interview, and the question was raised if drunk then the manager could not have sent him home in his own car, so it was claimed he was send home as he felt unwell. Not sure if that would have satisfied HSE, but he did not get sack, as the company is responsible while the employee goes to and from work.

So not sure how they have to deal with EV's? I know some one I work with was given a courtesy car which was an EV, without any charging lead, one way to ensure limited miles put on the clock. But was it because of safety, and not knowing if his supply was safe for use outside?

It is an on going thing EV charging, I tend not to take my charger with me on my EV e-bike, I could I am sure go into Morrisons cafe and plug the battery in while eating my meal, but the battery easy removes from the bike, so taking the battery in doors, and the charger is class II.

I saw the results of an earth mat connected to a PME supply, and the melted 4 mm earth cable, so I don't know what the result will be with EV charging points, and how to make them safe.
I must admit to being an electrical numpty, so I don't know what PME and PEN mean! However, there are pretty tough type approval rules for electrical isolation of electric cars. I don't think there's a big problem with electrocutions, though? You can read them here, if you're interested:


Except they don't call a battery a battery. They call it a REESS (Rechargeable Electrical Energy Storage System) so it can include batteries but also supercapacitors and any other future way of storing electricity!
No, the company doesn't pay for the fuel, except for the business miles - and that's something we're going to have to "come to an arrangement" on, if this is to go ahead! I'm also (cal me cynical!) not sure they're that bothered about my safety at home, but they'll be very bothered about their investment in a car, and my home insurers might get a bit snotty about paying-out, unless everything about the charger installation is to their satisfaction, if it were to torch itself and my house with it!
 
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It would seem that your 'Radio Teleswith' not only switches the meter between day and night registers at the appropriate times but also contains a 'switch' (relay/contactor) which switches the storage heaters on only during the cheap/night periods. I presume that the isolator (white thing below the teleswitch) contrails (i.e. allows you to switch off) the storage heaters?

Kind Regards, John
Thanks. I've never actually tried turning that switch off, but yes, I think it probably would!
 
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Thanks. I've never actually tried turning that switch off, but yes, I think it probably would!
As Sunray pointed out (I had not looked closely enough) that switch/isolator actually turns off everything in your electrical installation, not just the storage heaters.

Kind Regards, John
 

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