60 to 100amp fuse upgrade

[Jibjab]

It's just up to the installer's assessment of the installation and the likely total load. The charge point manufacturer won't know anything about that, as it's up to the installing electrician to assess the existing installation and ensure that anything he installs doesn't take the load current over that which can be safely handled by the installation.

As mentioned above, it's acceptable to put a peak reading clamp meter on the supply, leave it there for a day or two of normal household operation and use that as the basis for establishing whether or not it's safe to install a 32 A charge point. That's not information that any charge point manufacturer would know, as it varies a great deal from one house to another.

For example, as outlined above, a 60 A supply could be fine with a 32 A charge point for a house that doesn't present high normal loads on the supply. On the other hand, the same 60 A supply would definitely not be OK if the house had an electric shower that was in regular use, as that would probably draw over 40 A all the time it was on.

That all sounds really sensible It seems like a pre-requisite via Anderson to have a 100amp fuse though? I’ve decided that Anderson is the charger I would like installed. If the upgrade from the DNO to 100amp is really simple/quick then all will be fine. If not I’ll have to reassess I guess.

 

[Glan gluaisne]

That all sounds really sensible It seems like a pre-requisite via Anderson to have a 100amp fuse though? I’ve decided that Anderson is the charger I would like installed. If the upgrade from the DNO to 100amp is really simple/quick then all will be fine. If not I’ll have to reassess I guess.

The bottom line is that it isn't Anderson who sign the EIC and lodge the Part P chit, so all they can do is offer general guidance. The guidance that a 100 A supply *may* be required is sound, but it is just guidance. There is a general rule that MIs (manufacturers instructions) can overrule the requirements in the regulations in some areas, but only as far as the items that directly relate to their product.

As an example, many MIs state that their charge point needs to be supplied with a 6mm² cable, usually either SWA or NYY-J. Technically, 6mm² is over-sized for a 32 A load, in many cases 4mm² cable would be OK, in terms of both current rating and voltage drop. However, when the MIs state that 6mm² cable must be used, the warranty of the product may depend on this, perhaps because the manufacturer has tested and certified their product with 6mm², and wishes to ensure that all installations follow the method they used when testing.

No manufacturer, of any electrical appliance, can force the use of supplier-side electrical components, though. The most they can do is make it clear that the supply to their product is capable of safely delivering the required current, in this case 32 A. Technically, it would be fine to connect any AC charge point to a 40 A incoming supply, and I know of one installation that is wired like this, bit unusual, it's a converted Victorian school house that has a 3 phase incoming supply, at 40 A per phase, with the charge point on one phase, together with a few outside lights.

 

[Jibjab]

The bottom line is that it isn't Anderson who sign the EIC and lodge the Part P chit, so all they can do is offer general guidance. The guidance that a 100 A supply *may* be required is sound, but it is just guidance. There is a general rule that MIs (manufacturers instructions) can overrule the requirements in the regulations in some areas, but only as far as the items that directly relate to their product.

As an example, many MIs state that their charge point needs to be supplied with a 6mm² cable, usually either SWA or NYY-J. Technically, 6mm² is over-sized for a 32 A load, in many cases 4mm² cable would be OK, in terms of both current rating and voltage drop. However, when the MIs state that 6mm² cable must be used, the warranty of the product may depend on this, perhaps because the manufacturer has tested and certified their product with 6mm², and wishes to ensure that all installations follow the method they used when testing.

No manufacturer, of any electrical appliance, can force the use of supplier-side electrical components, though. The most they can do is make it clear that the supply to their product is capable of safely delivering the required current, in this case 32 A. Technically, it would be fine to connect any AC charge point to a 40 A incoming supply, and I know of one installation that is wired like this, bit unusual, it's a converted Victorian school house that has a 3 phase incoming supply, at 40 A per phase, with the charge point on one phase, together with a few outside lights.

Agreed...but it goes on to say “If you have 60amps, we will not be able to install your charge point. You will have to contact your Distribution Network Operator.”. Probably a non issue as long as it’s a simple upgrade, just wanting to research and arm myself with some information if required. I think I’ll have a chat with Anderson anyway. I think they may use their own installers as well as a newtwork, could be quite limiting if they’re demanding all installs must have a 100amp fuse.

 

[Glan gluaisne]

Agreed...but it goes on to say “If you have 60amps, we will not be able to install your charge point. You will have to contact your Distribution Network Operator.”. Probably a non issue as long as it’s a simple upgrade, just wanting to research and arm myself with some information if required. I think I’ll have a chat with Anderson anyway. I think they may use their own installers as well as a newtwork, could be quite limiting if they’re demanding all installs must have a 100amp fuse.

But it won't be Anderson that install it, it will be an electrician, perhaps sub-contracted to Anderson, who will do this. Anderson don't hold the required certification to install charge points, as they aren't listed as being a member of any of the Part P accreditation bodies.

The bottom line is that it's the installing electrician who carries all the responsibility for the installation safety, and compliance with all the applicable regulations, not the manufacturer of the product. Anderson have worded their guidance as if it were some sort of regulatory requirement, which is not something they have the authority to do.

If something goes awry on the supply side of the charge point, then it will not be Anderson that carry the can, it will be the installing electrician, and, perhaps, his/her insurer.

 

[Jason71]

Agreed...but it goes on to say “If you have 60amps, we will not be able to install your charge point. You will have to contact your Distribution Network Operator.”. Probably a non issue as long as it’s a simple upgrade, just wanting to research and arm myself with some information if required. I think I’ll have a chat with Anderson anyway. I think they may use their own installers as well as a newtwork, could be quite limiting if they’re demanding all installs must have a 100amp fuse.

I hope your DNO is not Western power then they completely refused to speak to me about a fuse upgrade. said they would only speak to the installer/electrician and only then via application of specific paperwork. Would not even come and do a survey to see what size fuse I had.

 

[MOBB]

Mine was UK Power and they couldn't have been more helpful.

 

[Glan gluaisne]

I hope your DNO is not Western power then they completely refused to speak to me about a fuse upgrade. said they would only speak to the installer/electrician and only then via application of specific paperwork. Would not even come and do a survey to see what size fuse I had.

If you want some fun, try self-build. Trying to deal with the utilities as a self-builder was a painful, as they just get deeply confused when the person doing the work and the end user are the same person.

 

[Jibjab]

I hope your DNO is not Western power then they completely refused to speak to me about a fuse upgrade. said they would only speak to the installer/electrician and only then via application of specific paperwork. Would not even come and do a survey to see what size fuse I had.

It’s northern power grid. So far it had been really simple. Called them, explained I required an upgrade, answered a few questions and sent me a site plan to confirm my boundary and meter location, just sent it back. Fingers crossed. The lowribeck engineer who fitted the SMETS 2 meter did mention that the power networks are/will be having pressure put on them to upgrade the ageing network in the push for solar/wind/power walls/EV chargers apparently. Double fingers crossed

 

[AndyS3]

I'm building a new house, the local DNO said I could only have 80A supply. Fortunately the fella who installed the meter put 100A fuse in.

 

[MrBadger]

I'm building a new house, the local DNO said I could only have 80A supply. Fortunately the fella who installed the meter put 100A fuse in.

Did he say/document that or you read if from the fuse holder?

Its common for the fuse holders to say 100A even if there is a lesser fuse installed. So fuse holder markings are not a guarantee of the true capabilities. It is however normally stated on the certificate that is given as part of the works compliance.

 

[Glan gluaisne]

Pretty much every reasonably new fuse holder I've seen in the past couple of decades has been marked 100 A, although many have fuses that are rated at 80 A, or sometimes 60 A. The only way to be sure is to pull the fuse, as more often than not the paperwork (if there is any) won't record the true fuse rating. The snag is that, by law only the DNO, or someone directly authorised by them, such as a suppliers meter installation company, is allowed to cut the seals and pull the fuse. Electricians are not permitted to pull the main fuse, unless they obtain permission from the DNO for that particular property. However, the law is wholly impractical to comply with in practice, so pretty much every electrician will have pulled a main fuse, not just to check the rating during an EICR, as that wouldn't be a valid reason, but usually when the supplier side of the installation needs to be isolated, for example when replacing a CU, fitting new tails, etc.

There are some very significant risks involved in pulling a main fuse, especially older ones, that may well have fragile fuse carriers. If there's a substantial current flowing though it there will probably be a hefty arc as it's pulled, plus there is always the risk of electric shock. Those who are authorised to pull a main fuse must wear the stipulated PPE, long rubber gauntlets plus a face shield, again a requirement that's often ignored in practice.

If anyone does pull the fuse for any reason, it's a lot of help for anyone doing an EICR in future if a label is put on the fuse holder giving the fuse rating. This is supposed to go on both the initial EIC and on subsequent 10 yearly, or when a the property changes hands, (for all domestic property) EICRs. Again, it seems that few people actually do comply with the regs and have their electrical installation inspected and tested every 10 years, one reason I do them for free for people. I've never yet done an EICR and found a perfect installation, either. I'd guess that few people do the required RCD/RCBO tests every 6 months, either, despite the prominent labels on CUs that are there as reminders. RCDs/RCBOs can, and regularly do, fail, hence the need to regularly check that they still work.

 

[Sean.]

However, the law is wholly impractical to comply with in practice, so pretty much every electrician will have pulled a main fuse, not just to check the rating during an EICR, as that wouldn't be a valid reason, but usually when the supplier side of the installation needs to be isolated, for example when replacing a CU, fitting new tails, etc.

Funily enough the sparkies on my reno project are doing just that tomorrow, as they’re fitting new tails to the isolator.

Makes a bit of a mockery of the utter faff when we first had the new supply energised when UKPN placed the cutout, their subby Siemens attached the tails at the cutout end that our sparks had provided and terminated at the isolator. Then UKPN super on the morning decided he didn’t like the look of our isolator....quick run to the wholesaler to get another isolator, before UKPN walk off in a huff.. after all that the meter supplier missed their appointment and we had no power anyway, until the strolled up the next day.

Felt like a scene with the vogons from hitchhikers guide to the galaxy

 

[interbear]

Thanks for the response. So is it an actual requirement to have 100 amp for a charging point? I was looking at the Anderson and it mentions 100amp, but wasn’t sure if that was just for the Anderson or a preference rather than requirement. The lady I spoke to at the power grid asked if I wanted 80 or 100, I believed I needed 100, but 80 would, potentially, be an easier easier install?

Western Power came to look at mine and based on the fact I don’t have a hot tub, electric shower or heated swimming pool advised me that 80amp would be more than sufficient. They changed it free of charge. If I’d insisted, or Western had advised that I should get a 100amp that would have incurred a fee as the fuse housing would have had to be changed apparently. £300 ish. Glad I didn’t have to that.

My charger is also an Andersen A2 by the way, they were also happy with it being a 80amp fuse.

 

[Glan gluaisne]

Funily enough the sparkies on my reno project are doing just that tomorrow, as they’re fitting new tails to the isolator.

Makes a bit of a mockery of the utter faff when we first had the new supply energised when UKPN placed the cutout, their subby Siemens attached the tails at the cutout end that our sparks had provided and terminated at the isolator. Then UKPN super on the morning decided he didn’t like the look of our isolator....quick run to the wholesaler to get another isolator, before UKPN walk off in a huff.. after all that the meter supplier missed their appointment and we had no power anyway, until the strolled up the next day.

Felt like a scene with the vogons from hitchhikers guide to the galaxy

When we were building this place some overhead and underground cables needed to be relocated away from the house, and I wanted them all to go underground. DNO agreed, costed the work, and I accepted that I'd pay them for the non-contestable work and we'd do all the contestable work (trenches, ducts, road crossings, making good, etc). They got shirty about this, and gave me a lengthy written spec for all the contestable work, down to specifying the exact manufacturer of cable duct (that didn't supply that particular type to anyone but that DNO).

We started digging the trenches and the local DNO guys rocked up, complete with a cable trailer with a roll of Wavecon 95 on the back. Said blokes asked if we could save them some hassle and just drop the cable directly in the trench, so they wouldn't need to pull it through the specified 150mm Rigiduct. When I told them we'd been told to put in the duct, and it formed part of the required spec from them, they laughed and said they never took any notice of what came from their head office, and they always directly buried Wavecon (which is fine). It all seemed to be fine, and when the jointing team turned up they actually said that they've have had to cut the duct off at the ends, had it been there, in order for them to place the intermediate earths from each joint in direct contact with the soil.

 

[Jibjab]

Western Power came to look at mine and based on the fact I don’t have a hot tub, electric shower or heated swimming pool advised me that 80amp would be more than sufficient. They changed it free of charge. If I’d insisted, or Western had advised that I should get a 100amp that would have incurred a fee as the fuse housing would have had to be changed apparently. £300 ish. Glad I didn’t have to that.

My charger is also an Andersen A2 by the way, they were also happy with it being a 80amp fuse.

Good to know about Anderson. I did have a brief chat with them and whilst 100amp is their preference it does depend on current load etc. Will see what the DNO says on their site visit. We do plan a hot tub at some point, and potentially a sauna, that’s in addition to the current air conditioning and usual cooking/utilities. If it’s £300 for an upgrade to 100amp that’s not as bad as I’d expected...knowing my luck we’d need to dig the whole drive up though!

 

[AndyS3]

Did he say/document that or you read if from the fuse holder?

Its common for the fuse holders to say 100A even if there is a lesser fuse installed. So fuse holder markings are not a guarantee of the true capabilities. It is however normally stated on the certificate that is given as part of the works compliance.

The application from Western power said 80A. The fuse is 100A They left the 80A spare inside the cabinet. The meter installer snaffled it.

 

[AndyS3]

Ive pulled several Fuses in the past, either when the old fuse wire type failed or needed to do some work on the CU.

 

[Glan gluaisne]

Ive pulled several Fuses in the past, either when the old fuse wire type failed or needed to do some work on the CU.

I doubt there's an electrician in the country that's never broken the law by pulling a main fuse, TBH.

Can't be many BS3036 main fuses still around, though, I've not seen one in decades, now, only HRC cartridge main fuses. Only place where I've regularly seen BS3036 fuses around are on older CUs, often the solidly built Wylex ones, that seem to last for ever.

I used to teach electrical engineering science, as a part time job, to SWEB apprentices 40 odd years ago, and even in the rural south west back then BS88 type cartridge main fuses were standard. I seem to remember there was a mandatory replacement scheme for all the old BS3036 main fuses, as many of the fuse holders contained asbestos, must have been around the time everyone was panicking about removing asbestos from everything.

 

[WarwickPete]

Thanks for the response. So is it an actual requirement to have 100 amp for a charging point? I was looking at the Anderson and it mentions 100amp, but wasn’t sure if that was just for the Anderson or a preference rather than requirement. The lady I spoke to at the power grid asked if I wanted 80 or 100, I believed I needed 100, but 80 would, potentially, be an easier easier install?

I had an Andersen installed 4 weeks ago and they wanted me to show that I had an 80amp fuse before the installation, which I couldn’t do as the fuse was sealed and the label had been scratched off. I contacted Western Power and they were happy to arrange a free inspection and if necessary a free upgrade to 80amps. They told me that a 100amp fuse would be unusual and was more commonly used for commercial premises
.
This fuse inspection/upgrade was cancelled twice by them - staff shortage and then local storm damage - but only took about 15 minutes when they did come, a month later than initially planned.

The clever bit, I thought, was that the Andersen installation was allowed to go ahead but with it set to 16amp charging, then when I could prove I had the 80amp fuse with a photo, they switched the charger to 32amps remotely in a matter of minutes.

As an aside, the Andersen installer was a direct employee (I asked) and he did a very neat job with no visible cables.

 

[Sean.]

I doubt there's an electrician in the country that's never broken the law by pulling a main fuse, TBH.

Can't be many BS3036 main fuses still around, though, I've not seen one in decades, now, only HRC cartridge main fuses. Only place where I've regularly seen BS3036 fuses around are on older CUs, often the solidly built Wylex ones, that seem to last for ever.

I used to teach electrical engineering science, as a part time job, to SWEB apprentices 40 odd years ago, and even in the rural south west back then BS88 type cartridge main fuses were standard. I seem to remember there was a mandatory replacement scheme for all the old BS3036 main fuses, as many of the fuse holders contained asbestos, must have been around the time everyone was panicking about removing asbestos from everything.

Had a quite a big reconfig going on today. The lads had to yank our 200 amp 3-phase main fuses today so they could pull new tails to a new splitter box. This splitter feeds an ABB isolator (the previous Eaton is still in the pic) for the house, as well as a separate ABB isolator for the charger.

Go big or go home!