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I’m surprised they didn’t fit a smart meter. I thought all suppliers were pushing for them.
I take it that’s because of rural setting and maybe bad mobile signal for the smart communications.
A couple of recent customers have told me they have been contacted by their suppler to book in fitting a smart meter only to be told they can't have one as they have off peak which isn't supported. The whole system is a joke.
 
A couple of recent customers have told me they have been contacted by their suppler to book in fitting a smart meter only to be told they can't have one as they have off peak which isn't supported. The whole system is a joke.
We've also seen more than one example of this forum of smart meter installers not understanding off peak metering and having a go anyway, resulting in RCD's tripping every night...
It might not be such a bad thing if smart meter installers avoid these installations!
 
The better EV charges have a current transformer for the main supply and will adapt the charging to keep your total below 60A (assuming the house is below 60 of course!)

So if charging and you put on an electric shower it just throttles the car charge for 10 minutes or whatever you are using it for.

Bigger issue is if you plan lots of electric heating or a massive range-style cooker, though I think some of the fancy induction ones also have total demand throttling (or am I imagining that?)
Thanks pc1966
Interesting what you said on EV chargers with transformers.
Yes - the other thing I'd looked at is air source heat pump. My research suggests system design is a more constant background heating - less cyclic than your 20Kw typical gas boiler system. For larger older houses you'd need probably a min 4Kw system but run all the time in cold weather.
A lot of rural houses have no gas, so rely on oil / LPG. If this is phased out that leaves night storage / heat pumps.
Add EV to the equation and frankly I don't see how long term the grid will handle it all.
 
A couple of recent customers have told me they have been contacted by their suppler to book in fitting a smart meter only to be told they can't have one as they have off peak which isn't supported. The whole system is a joke.
Yes - the installer said that as it's economy 7.
Frankly I think I need to review the benefits now. Economy 7 used to be around half price. Now it's 22p day and 16p night, not a big difference any more.
 
Thanks again for replies.
I've just looked up looped supply and now understand the concept.
Do SSE have accurate records of whether I am on a looped supply, and the supply cable size(s) ? 35 years ago !!
We are very rural, in one of a pair of cottages fed from overhead. The overhead runs about 400 yards to a more substantial set of overheads. I remember 35 years ago the linesman who installed our supply saying there is a 400 amp switch box there for isolating our overhead.
I think this might be expensive - or I just abandon it all and forget the EV charging 'future proofing'. Keep to petrol !!
I'll contact them tomorrow - maybe they will do a survey.
I'd have preferred my electrician to do this but he's ill at the mo.
Thanks all for your support and replies. Though I'm not an electrician I can understand all your replies and what the fundemental issues are.
When you apply for an EV charge point, you have to request permission from your supplier, it's a standard form which is available here https://www.energynetworks.org/assets/images/Resource library/Single-Electric-Vehicle-Charge-Point-and-Heat-Pump-Installation-Application-Form.doc

They then check their network diagrams, loadings etc before you can connect an EV charge point.

You can submit one yourself any time so consider putting one through and you will get your answer without any commitment on your part.

Note it's the same form if you want to install heat pumps as well.


Note, the fuse carrier states 100A as this is the maximum, just like a standard plug says 13A - you could have a 3A, 5A.... etc fuse installed.

One point is to look at the meter, it usually has a maximum of 80A, so that's a clear indication you wouldn't have a 100A fuse!
 
That’s the funny thing;
Our test certificates asks us to fill in a box what size the main fuse is…. But we are not allowed to pull it to find out

we have to go by the sticker on the fuse carrier… which in experience … is either “100A” or “60/80” which still doesn’t help… which is it? 60 or 80?
The carrier is moulded with 100A printed into the plastic, as others have said, that’s the rating of the carrier- the biggest fuse that can go in.

I’m surprised they didn’t fit a smart meter. I thought all suppliers were pushing for them.
I take it that’s because of rural setting and maybe bad mobile signal for the smart communications.
With all the regs changes covering even what sparks can have for lunch, I'm surprised that correct labelling of the main fuse isn't mandetory within regs. At work if we supplied any equipment everything HAD to be correctly labelled. Seems a bit odd to me that the DNO can have a blasé approach just because it's their fuse.
My main fuse was labelled 100amps, not moulded. The meter fitting guy scratched up the label so now you can't really read it at all.
 
When you apply for an EV charge point, you have to request permission from your supplier, it's a standard form which is available here https://www.energynetworks.org/assets/images/Resource library/Single-Electric-Vehicle-Charge-Point-and-Heat-Pump-Installation-Application-Form.doc

They then check their network diagrams, loadings etc before you can connect an EV charge point.

You can submit one yourself any time so consider putting one through and you will get your answer without any commitment on your part.

Note it's the same form if you want to install heat pumps as well.


Note, the fuse carrier states 100A as this is the maximum, just like a standard plug says 13A - you could have a 3A, 5A.... etc fuse installed.

One point is to look at the meter, it usually has a maximum of 80A, so that's a clear indication you wouldn't have a 100A fuse!
Thanks for the detail and esp the form link.
I have looked at my photo of the original meter - and yes it says 80 amps. Must admit I hadn't thought to look at it.
 
Can the op not use the off-peak for the car charging then?

I asked this ? I presume the economy 7 is the same as our day/night metering

Is there not enough spare capacity at night with the throttling u can do or is it because you specifically can't get permission on the 15kva supply here ?
 
In fairness to your Spark assuming that it was a 100 amp fuse installed is not the same as not knowing that it might not be.
Everyone makes incorrect assumptions at some point or another.
As previously stated some suppliers frown on pulling the main fuse.
Admittedly there were indications that it wouldn't be 100A but again it could have been a genuine mistake / brain fart / poor assumption rather than a lack of knowledge.

There is a thread on here somewhere about the daft things we have done as electricians that shows even talented knowledgeable tradesmen get it wrong sometimes. :)
 
When you apply for an EV charge point, you have to request permission from your supplier, it's a standard form which is available here https://www.energynetworks.org/assets/images/Resource library/Single-Electric-Vehicle-Charge-Point-and-Heat-Pump-Installation-Application-Form.doc

They then check their network diagrams, loadings etc before you can connect an EV charge point.

You can submit one yourself any time so consider putting one through and you will get your answer without any commitment on your part.

Note it's the same form if you want to install heat pumps as well.


Note, the fuse carrier states 100A as this is the maximum, just like a standard plug says 13A - you could have a 3A, 5A.... etc fuse installed.

One point is to look at the meter, it usually has a maximum of 80A, so that's a clear indication you wouldn't have a 100A fuse!
Hello Andy.

Don't panic! The advantage of remaining at 60 amps if you can is that there is less fault energy present (therefore less damage) if something nasty goes wrong at the meter head or consumer unit. With LED lighting, improved insulation and improved technologies, domestic loads are reducing and you may be surprised to find your load current is significantly lower than the original circuit capacities. As posted above, many EV chargers can phase back when required to. I'd be surprised if a domestic cottage today got anywhere near to blowing a 60 amp fuse. Regards, Colin Jenkins.
 
Thanks everyone for the past inputs - it's been very helpful.
Updates:
I finally got through to SSEN and after much waiting got through to a 'connections' dept. They couldn't find any relevant data on my house, but asked for an email with detailed request, plus photos of meter / fuse and outside shots. The guy on the phone said he had no access to records such as fuse fitted or whether we were on a loop supply from next door.
Had chat with next door - we are both convinced there are two separate supplies from the gable end point. A new run would be required along the front of both houses as the back is now covered by various extensions making running here impractical.
So photos taken and Thursday got round to putting it all in email.
Blow me - Friday morning had a reply that they will put together a quote - and I might have to pay towards the quote. ??
Staggering - this afternoon I got a quote - £65 to change the main fuse to 100 amps
No mention that the existing cabling is adequate - but presume it is ?
 

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Firstly, snap their hand off!
With caveat that I'm never great at telling cable sizes from photos, so my impression is:
From the DNO's point of view the tail sizes (25 sq mm) are adequate for 100A as far as the isolator switch (and a bit further to where they split and change to old colours).
It's virtually certain that the loading on each board is within the capacity of the red/black 16 sq mm tails, and I think you said the garage supply will be fused at 60A so the future use with EV should be ok.

Two things bothering me a bit:
Looks like no grommet/tails gland on the Switched Fuse (presumably for garage on right) where tails enter.
As it's PME I'm particularly interested (and having difficulty) deciding what size those earthing conductors are....are they all 16mm? Looking more like 10mm to me.
 
Firstly, snap their hand off!
With caveat that I'm never great at telling cable sizes from photos, so my impression is:
From the DNO's point of view the tail sizes (25 sq mm) are adequate for 100A as far as the isolator switch (and a bit further to where they split and change to old colours).
It's virtually certain that the loading on each board is within the capacity of the red/black 16 sq mm tails, and I think you said the garage supply will be fused at 60A so the future use with EV should be ok.

Two things bothering me a bit:
Looks like no grommet/tails gland on the Switched Fuse (presumably for garage on right) where tails enter.
As it's PME I'm particularly interested (and having difficulty) deciding what size those earthing conductors are....are they all 16mm? Looking more like 10mm to me.
Hi Tim
Thanks for your reply and keen observations.
You are correct on all counts.
As the original meter economy 7 clock was faulty my electrician (Dan) suggested getting the meter changed and ask for an isolator. It was £60 charge to me for the isolator, but Dan said it will make life much easier on bringing the rest up to spec. The meter guy also fitted new blocks to take 25mm which helps further.
Yes - the earths are undersize - so they are now due to be changed to 16mm throughout, plus upping the tails elsewhere as appropriate.
Yes - I'm frankly astounded that DNO can just change the fuse, I was expecting a couple of grand quote for upgrading their supply cable from next door's gable. I presume they have historic record of their cables. FYI the supply in is only 13.5 mm OD (just measured with vernier). Seems small for 100A ?
We are planning a new 16mm SWA to the outbuilding, plus retain the existing 10mm SWA and use that only for shed and garage (and EV point one day). So we'll have 60A capable for outbuilding, plus 40A for shed / garage.
We are assuming 40 amps for shed garage should cover a typical EV charge point.
Both SWA's will have new boxes with I think Dan said RCBOs ?
Currently I have one of those 'self fit' garden supplies that plugs in a house socket with an RCD and flex to a box outside. It used to be fine but the pond pumps throw out half of the house consumer unit when faulty (already replaced 1 pump)
So all that will get reorganized and garden stuff come off the shed supply.
Need new consumer unit in outbuilding plus new smaller units for shed and garage.
Plus change the house consumer unit for metal as it's near the stairs.
So a lot to do !

BUT - with the recent hike in electricity prices I will be looking carefully at our energy - we are using too much generally. So insulation projects plus things like change hob from ceramic to induction. Hoping long term that 100A fuse will have little to do most of the time !

Dan will be busy - hoping insulation tests on the existing house wiring goes ok.
 
I'm not an expert in EV chargers, but I'm given to understand that if you have a looped supply, and a 60 amp supply, then unfortunately both of these are hurdles that will need overcoming.
I've heard of instances where DNO (SSE) will unloop without charging. Others know more about this area of electrickery than me.
Some dnos will allow you to fit an ev charger on a 60a loop supply subject to load balancing with use of wired ct clamps or harvis such as the zappi stuff.
Most will get a bit jittery about it. In my experience ssen are a nightmare to deal with and try to charge for everything. On a positive they do allow fuses to be pulled.
Wpd are brilliant will unloop and upgrade to 80/100 amps at same time free of charge.
If customer doesnt want the groundworks they usually say fit charger subject to complying with g100 and ena guidance which brings us back to ct clamps either from the chsrger or third party.unit such as the matt:e..
A 40amp supply to an outbuilding would work for a charger subject to volt drop etc as the Myenergi zappi cam work off submains and load balance this and the house.
Just need yo understand the ct settings and groups etc within the menus. Its demonstrated in the Myenergi wiki and tech support.
I did.one recently. The garage/office had a 40 amp feed, by setting up the kit correctly power lights and an electric shower in there are all working.alongside a charger due to load balancing.
Its all in the planning
 
Yes - I'm frankly astounded that DNO can just change the fuse, I was expecting a couple of grand quote for upgrading their supply cable from next door's gable. I presume they have historic record of their cables. FYI the supply in is only 13.5 mm OD (just measured with vernier). Seems small for 100A ?
It's not uncommon to be scratching our heads about the lengths we are obliged to go to running big enough cables within the installation when the incoming supply is a fairly small cable.
But the DNO has different rules, the BS7671 rules we sparks work to start at the end of the meter tails or isolator and are a lot more conservative.
I'd accept the quote and see what the person tasked with doing it says they turn up.
 
Some dnos will allow you to fit an ev charger on a 60a loop supply subject to load balancing with use of wired ct clamps or harvis such as the zappi stuff.
Most will get a bit jittery about it. In my experience ssen are a nightmare to deal with and try to charge for everything. On a positive they do allow fuses to be pulled.
Wpd are brilliant will unloop and upgrade to 80/100 amps at same time free of charge.
If customer doesnt want the groundworks they usually say fit charger subject to complying with g100 and ena guidance which brings us back to ct clamps either from the chsrger or third party.unit such as the matt:e..
A 40amp supply to an outbuilding would work for a charger subject to volt drop etc as the Myenergi zappi cam work off submains and load balance this and the house.
Just need yo understand the ct settings and groups etc within the menus. Its demonstrated in the Myenergi wiki and tech support.
I did.one recently. The garage/office had a 40 amp feed, by setting up the kit correctly power lights and an electric shower in there are all working.alongside a charger due to load balancing.
Its all in the planning
Many thanks for reply.
I'm convinced now we are not on a loop supply. Looks like two feeds come off the gable, so one for nearest half (No1) and one for us (longer run to No2).
Next door at No1 there is only one supply cable terminating at their main fuse.
All good stuff there Gavin for me to learn ref the EV charging - appreciated !
 
It's not uncommon to be scratching our heads about the lengths we are obliged to go to running big enough cables within the installation when the incoming supply is a fairly small cable.
But the DNO has different rules, the BS7671 rules we sparks work to start at the end of the meter tails or isolator and are a lot more conservative.
I'd accept the quote and see what the person tasked with doing it says they turn up.
Yep - I'll accept and post an update. Though they have said up to 8 weeks !!
I meant to say, I could see no evidence of a looped supply in the photos.
Do report back as this job unfolds, it's an interesting one!
Will do Tim. Many thanks
 

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