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2022 Tesla Model 3LR
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Discussion Starter · #1 ·
Had my charger fitted yesterday. Installer checked and I have an 80A main fuse which I thought was good - he’s set the charger to grid limit at 80 just in case but we don’t have electric showers or heating so I doubt we’ll ever get near that.

Should I still inform the DNO? I’m fine if they do a free upgrade to 100A but I don’t want to pay for one if I don’t need it. (meter etc all ready for 100A so should just be a fuse swap)
 

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I'm doing it the other way around - getting my fuse upgraded and an isolator switch installed BEFORE the charger is installed. We have quite old electrics. The DNO has just upgraded my main fuse from 63A to 100A. Their main concern was whether the cable into my house was so old it would need an upgrade in itself. But it was OK and so it was simply a fuse upgrade (I wasnt expecting to end up at 100A, I thought it would be 80A). It was all quite efficient with the DNO (Northern PowerGrid), about 2 weeks from request through to site survey and then install. No charge.

If you've got no other heavy draws on your electricuity, I would guess that 80A would be sufficient. But I'm not an electrician!

Waiting for Octopus to install an isolator switch between the consumer unuit and the meter (and also upgrade the meter to SMETS2) feels much slower.
 

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Kia e-Niro 4 MY20, Zoe Z.E.50 GT Line
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It depends on the dno and the local supply setup. In my case Northern Powergrid upped the fuse from 60 to 80 amp. If I wanted 100A that would have been chargeable. Our supply cables are all overhead, quite old and supply a lot of homes. I can see lots of requests for 100A causing some concern. Worth noting that an 80A fuse is in a 100A carrier, it doesn’t say what the actual fuse rating is.

Given we will all, mostly, change cars over night this isn’t really any problem but it’s surprising how high draw can potentially be. In the unlikely event we ran all our white goods, kettle, oven and car, could top 80A. Of course that doesn’t actually happen which is why electricians talk about diversity calculations. That gets a bit more interesting as we start thinking about replacing gas boilers with heat pumps and gas hobs with induction.

The clamp on the charge point works as a precaution so it’s worth having in place.
 

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2020 VW ID3
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Had my charger fitted yesterday. Installer checked and I have an 80A main fuse which I thought was good - he’s set the charger to grid limit at 80 just in case but we don’t have electric showers or heating so I doubt we’ll ever get near that.

Should I still inform the DNO? I’m fine if they do a free upgrade to 100A but I don’t want to pay for one if I don’t need it. (meter etc all ready for 100A so should just be a fuse swap)
My understanding is that the charge point installer has to do the calculation on what fuse is needed then you have to apply for that change by the DNO. If no change is needed, you just have to notify them about the installation of the charge point.
 

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Had my charger fitted yesterday. Installer checked and I have an 80A main fuse which I thought was good - he’s set the charger to grid limit at 80 just in case but we don’t have electric showers or heating so I doubt we’ll ever get near that.

Should I still inform the DNO? I’m fine if they do a free upgrade to 100A but I don’t want to pay for one if I don’t need it. (meter etc all ready for 100A so should just be a fuse swap)
The installer had to inform the DNO that an EVSE has been installed regardless of the Fuse Rating.
 

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My understanding is that the charge point installer has to do the calculation on what fuse is needed then you have to apply for that change by the DNO. If no change is needed, you just have to notify them about the installation of the charge point.
No, the installer does not dictate to the DNO re the fuse size, it doesn't work like that.
 

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2022 Tesla Model 3LR
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Discussion Starter · #10 ·
We have no idea. Ask your DNO. Their answer will be correct, unlike speculation here.
well sure. I just wanted some input whether 80 was likely enough. I don’t want to be forced to pay more if 80 is fine. When I was reading up it talked about 60A maybe needing to be upgraded to 80/100 so maybe it’s ok.
 

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well sure. I just wanted some input whether 80 was likely enough. I don’t want to be forced to pay more if 80 is fine. When I was reading up it talked about 60A maybe needing to be upgraded to 80/100 so maybe it’s ok.
I'm sure it'll be fine too. Like most owners, you'll probably charge mostly at night.
For your info, an 80 amp fuse will take lots more for some time before it goes pop.
 

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I have 80amp main fuse with 32amp charger. Installer (Pod Point) didn't suggest I upgrade main fuse.
 

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80amp should be well enough, the DNO can't just upgrade everybody's fuse to 100amp, there are reasons for certain cutouts to be graded at 60, 80, or 100.
Most fuse carriers will say 100 amp on the side, this only refers to max amp for that carrier, not what's inside although, if you've had any work done in last 10 years on your meter, the correct fuse inside the carrier should be additionally labelled on the carrier.
 
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