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Bmw i3s 120ah 2019
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I don't think its right.
If I would put oven on or heating(underfloor heating) or neighbour will turn on electric shower it will be blowing fuses.
Any idea what can I do about it?
 

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If you are concerned might be worth calling Ryan (number on the top right of the letter) and having a quick chat about your setup. Explain that you understand what he’s saying about don’t exceed it, but there will be times it’s unavoidable and ask what options there are. Worst case he reassures you everything is fine and correct, there’s nothing to loose from asking the question? (Unless he says “oh, you’ll need unlooping at your own cost… 😬)
 

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If I would put oven on or heating(underfloor heating) or neighbour will turn on electric shower it will be blowing fuses.
The 60A supply is only you, they have a 60A supply also.
Look at how you will charge, many use Octopus Go from 00.30 to 04.30 and so little chance of ovens or showers then.
 

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Worth remembering that a 60 A main fuse won't blow at 60 A. In fact even at 80 A it would need that current to flow for around 3 hours to blow. In reality, diversity means that most high loads, like a cooker, shower etc will only be running at full power for a short time, and not long enough to blow the main fuse.
 

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You can also get a charge point that automatically drops the charge rate to stay within a defined threshold. A lot of them can do this with the appropriate current sensing clamp.
 

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Did i not read that there has been/will be legal changes so that the DNO has to unloop if customer requests it at the DNOs cost ?
 

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Did i not read that there has been/will be legal changes so that the DNO has to unloop if customer requests it at the DNOs cost ?
I believe those rules are already in place.

I suspect Northern Power grid are hoping the OP will not be aware of this rule.

That said unlooping may cause some disruption (ie digging up the drive / garden) and may be a challenge if the unlooping requires work on the neighbour's property which the neighbour refuses.

Unlooping and DNO fuse upgrade will give the best future proofed solution - a load sensing charger may be the solution with least effort / disruption.
 

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Whilst @Jeremy Harris is correct about the fuse only blowing well above the rated value, diversity etc. it's a good idea to take advantage of the current rules requiring the DNO to do the unlooping for free. Power usage is only likely to increase in the future with the switch to heat pumps and the low cost overnight tariffs or the time of your usage may change meaning that you want to charge at a time when you have other significant loads. Kicking the can down the road is for politicians and others who move on before the problems come home to roost, so unless you plan to move soon get it done.
 

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I agree, push the DNO to unloop, but they can decide to dig their heels in and refuse, if the existing supply is deemed adequate. The current rule doesn't mandate that a DNO has to unloop a supply, all it mandates is that they must ensure a supply of sufficient capacity to allow car charging, in addition to the house normal load, is available

Some DNOs will just unloop supplies without hassle, some need persuading, and some may just say there is no need to do it, and if they can show that the supply is adequate to deliver the existing house load plus a 32 A charge point then they cannot be forced to increase it further.

At the moment, they are stating that the supply is adequate, as long as the house load doesn't exceed 45 A (with a diversity allowance). They could prove this easily by fitting a load monitor on the supply for a week to see what the actual house demand is. If they find it's less than the 45 A they've allowed, then they can just do as they have said, and leave it at 60 A.
 

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At the moment, they are stating that the supply is adequate, as long as the house load doesn't exceed 45 A (with a diversity allowance). They could prove this easily by fitting a load monitor on the supply for a week to see what the actual house demand is. If they find it's less than the 45 A they've allowed, then they can just do as they have said, and leave it at 60 A.
I believe the "in practice" is irrelevant, it is the theorectical which counts. Might sell the house next week and the new occupant will behave differently. If the DNO plays up threaten to and then do complain to Ofgem, they dont like that as there is a cost to them and blotting the copy book.

An electric shower 45A (no diversity), a car charger 32A and the rest is way over 60A . 60A is useless in this day never mind about tomorrow.
 

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I believe the "in practice" is irrelevant, it is the theorectical which counts. Might sell the house next week and the new occupant will behave differently. If the DNO plays up threaten to and then do complain to Ofgem, they dont like that as there is a cost to them and blotting the copy book.

An electric shower 45A (no diversity), a car charger 32A and the rest is way over 60A . 60A is useless in this day never mind about tomorrow.

I'm not disagreeing, just stating facts. The facts are that the DNO only HAVE to unloop a supply if it cannot meet the requirements of the existing installation plus 32 A for a charge point. If they want to get arsey, and decide to fit a monitor to the supply to see what the existing load is, they could. If it turns out that the existing demand is low enough to allow a charge point to be fitted, then legally there is not a damned thing anyone can do to force them to upgrade the supply FOC.

I agree, 60 A may not be adequate for some installations, but then again it's absolutely fine for others. For example, we could very easily have coped with a 60 A supply when we were only using one charge point, as even with an all-electric house, with electric heating and electric water heating, with no other form of energy used at all (no gas, oil, solid fuel, or whatever) our maximum load, excluding charging the car, was only ever about 5 kW, so around 22 A. With a 32 A charge point as well we were still only topping out at about 54 A, although I never actually saw our demand get that high in reality. Now we have two EVs and two charge points we have had a couple of nights when we've hit around 75 A, so although we have a 100 A supply we could probably run two charge points and the house from an 80 A supply with no issues at all.
 

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The requirement isn't just to support EV charging but also A/GSHP. There's also no requirement to complete the work, so you could be disingenuous and say that you plan to fit 2 x charge points and a 7kW heat pump meaning that you'd be pushing 100A on those alone. Just beware that they might insist that you install 3 phase which they can charge you an arm and a leg for.
 

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The requirement isn't just to support EV charging but also A/GSHP. There's also no requirement to complete the work, so you could be disingenuous and say that you plan to fit 2 x charge points and a 7kW heat pump meaning that you'd be pushing 100A on those alone. Just beware that they might insist that you install 3 phase which they can charge you an arm and a leg for.
Our heat pump is 7 kW. Uses less power than a kettle to run. You'd need a really big heat pump to require any supply upgrading, now that pretty much all of them are inverter controlled. The reality is that our 7 kW heat pump tops out at a bit under 2 kW input for the first minute or so after firing up, then settles down to run at about 800 W input. Something like a 25 kW heat pump would draw about the same as a charge point, and very few homes are ever going to need anything like that much heating.

As far as free supply upgrading is concerned, the DNO aren't under any obligation to do this for two charge point installations, only the first one. They don't like doing this if the local LV distribution network is already running at capacity, either, as if they need to do a PMT change, for example, the cost to them will be around £12k to £15k or so. They will try hard to find a way to wriggle out of doing anything for free that involves them in doing this sort of work, and I've heard a few horror stories of the prices they've tried to squeeze out of customers for just a modest upgrade. It's not unusual for this to be a sore point with self-builders, as often the DNOs (and the utility companies) view self-builders as way to get upgrades done to their local network on the cheap (Wessex Water tried exactly this trick with me).
 

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So who contacts the DNO about unlooping , it the user beforehand or the installer of the charger.
 

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So who contacts the DNO about unlooping , it the user beforehand or the installer of the charger.
Depends. Should be the installer, but there have been cases reported here of installation companies getting customers to do it, probably just them cutting corners, as the bottom line is that the installer is the one putting his/her signature on the chit to say a total load assessment has been undertaken and that the load will not exceed the supply capacity.


Can the DNO grant permission on the condition that the charge point has total-house load limiting ?
Generally the DNO don't grant permission. The process is that they need to be informed after the installation is completed, if it's just for a single charge point of up to 32 A. The onus is on the installer (i.e. the person physically carrying out the work) to do the total load assessment, and the installer can take the load limiting capability of a charge point that has it into account, in much the same way as they will take diversity into account for some other loads within the installation.
 

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I have a 60A main fuse on a looped supply (well it looks looped - two wires going into the cutout)
Installer was more than happy to install a Zappi with load balancing.
We don’t have electric heating or shower - only large load appliances are Oven, Dishwasher and Washer/Dryer.
I’ve not heard anything from DNO since the installer did all the paperwork for the grant etc. This was back in November 2020.
 

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It's not unusual for this to be a sore point with self-builders, as often the DNOs (and the utility companies) view self-builders as way to get upgrades done to their local network on the cheap (Wessex Water tried exactly this trick with me).
Likewise after a lengthy disconnection (~3 months) initially for safety whilst rebuilding a house Western Power tried to claim ours was a new connection rather than a reconnection and that our house alone would exceed the capacity of the existing transformer that served three houses. Eventually they backed down and 15 years later and the addition of 2 x 32A charge points they still haven't replaced the transformer.
 

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Generally the DNO don't grant permission. The process is that they need to be informed after the installation is completed, if it's just for a single charge point of up to 32 A. The onus is on the installer (i.e. the person physically carrying out the work) to do the total load assessment, and the installer can take the load limiting capability of a charge point that has it into account, in much the same way as they will take diversity into account for some other loads within the installation.
According to this flowchart, there are some circumstances where you need to apply to connect - I was wondering if they have the option to stipulate that load-limiting is implemented in cases where they might otherwise refuse.
 

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According to this flowchart, there are some circumstances where you need to apply to connect - I was wondering if they have the option to stipulate that load-limiting is implemented in cases where they might otherwise refuse.

As far as I know, the DNO cannot stipulate a load limiting charge point under normal circumstances, although an installer can, and should if he/she concludes that the supply limit might be exceeded without it.

There may still be consultation going on regarding the DNOs being allowed to control smart meters for load limiting (this was one original motivation for them). That's been on hold for ages, but the original plan was that smart meters would allow better load shedding and staged reconnection in the event of a major grid problem, hence the reason they have a remote supply disconnect contactor inside. This was an extension of the automatic load shedding agreements some industrial customers agree to, in return for lower tariffs from suppliers. If there's a grid problem, the DNOs can turn off supplies, based on the priority level assigned to each user. The plan was that making domestic consumers first tier load shedding targets would be less disruptive than shutting down businesses.

I think that for the majority of charge point installations the DNO would be obliged to ensure that a supply capable of meeting the existing demand, plus that of a single 32 A charge point, would be an "install and notify" except for a few cases where there were other considerations. From the experience of a few here, it seems that some DNOs are quite cooperative when it comes to uprating supplies, including unlooping. I have a feeling there may be something written into ESQCR about this, if I get time tomorrow I might have a read through it and see if there is anything in there. If so, then it places a legal obligation on the DNOs, so could be useful if they start getting a bit awkward.
 
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