House fuse

[JonathanP]

May not be the correct place to post the question, so please move if it's in the wrong forum.

My house only has a 60amp fuse and an electrician today said that an 80amp fuse would be better.

I found a website that said they upgrade at no cost for EV, but they don't cover the midlands. It used to be western power around us, but I can't find anything and end up just at the national grid website but then it asks me about a new supply?

Am I better off trying to call someone?

[ernieb]

Check this out:

https://media.umbraco.io/uk-power-networks/zclm22n2/fuse-upgrade-guide-march-2021.pdf

I looked at this some time ago as I have a 65A incoming fuse. I seemed to get to the part when they suggest you look at the cut out box, if it's plastic then you're probably going to be OK if like mine it's pitch covered them it's no go.

[philip42h]

As I understand, the supply cables up to and including the fuse are owned by UK Power Networks - so you need to go through them directly or indirectly to upgrade the fuse. https://www.ukpowernetworks.co.uk/i-already-have-electricity-domestic/adding-more-power/fuse-upgrade

If, as Ernie's link suggests, you have an older style supply wiring and cutout, you would need a new/replacement supply. There's information on how to get that done on the UK Power Networks site. https://www.ukpowernetworks.co.uk/i-already-have-electricity-domestic/adding-more-power/what-do-you-need-to-upgrade

In practice I went through this process a few years ago - building works required the we moved a supply pole which, obviously, necessitated replacing the supply wiring from the new pole to the meter. It took a while to get it all organised but I don't recall it being excessively traumatic ... 😉

[ChrisON]

Mine is 60 amp - one in the plastic housing. The Zappi 2 operates with no issues. We had the house rewired about 18 months ago and the solar/Zappi installed in March and there was no mention of a need for a higher rated fuse.

Chris

 

[JonathanP]

28 minutes ago, ChrisON said:

Mine is 60 amp - one in the plastic housing. The Zappi 2 operates with no issues. We had the house rewired about 18 months ago and the solar/Zappi installed in March and there was no mention of a need for a higher rated fuse.

Chris

 

He did say that the Zappi can be set to know the house fuse, because we already have an electric cooker, hob, shower etc he said that a 80amp fuse would give more wiggle room.
If it's set at 60amp it will still work fine, but the amount of electricity that Zappi can use will be reduced if other things are in use.
I don't suppose it's a massive issue, as if we are wanting to charge the car mainly from solar we are likely to be out enjoying a walk in the local area. 🙂

Still waiting on a quote as he said our consumer unit is a little old and he's going to do a quote for replacing that or simply putting an extra one on for the Zappi itself.
Anyone any idea how much a new consumer unit is likely to set me back? The comsumer unit I have must be a good 18 years old as the house was rewired before we moved in.
At least we don't have old fashioned fuses 🙂

[ChrisON]

 

 You are looking at about £100-£150 depending on how many RCDs you need - a populated 8 way from Screwfix is just over £100. I'd guess if your sparky supplies one it will probably be more.

I probably micro-manage the car charging a bit and always wait for surplus solar (as much as l can in this country - this last week has not been great for solar)  so never really exceed the Zappi's 7kW max. On rare occasion i do need a bigger charge i do it overnight so it doesn't conflict with the house demand. Winter may be different...we'll see.

 

Chris

 

[Mooly]

A 60 amp fuse is good for almost 14kW loading. You need the advice of a qualified electrician in the first instance as to what is possible and legal. It all depends on the rating of your consumer unit and the size of the cables feeding the incoming supply to the meter.

A 7.4kW home charger takes close to 33 amps.

Curiously this is or could be a big issue for me as we are 'all electric' on E7 and although I have a 100A supply it would be insufficient for overnight charging of an EV when the other electrical consumers are taken into account. Worst case and I reach 20kw loading or just over during the night period. That would only leave around 3kW headroom available.  

[flash22]

Contact your DNO your incoming main may need to be upgraded or the Head and/or meter replaced

https://www.energynetworks.org/customers/find-my-network-operator

[Mister Mike]

We had a 60A mains supply to our (very old) house. With a charger consuming 32A for hours on end, you can be dangerously close to blowing the 60A house fuse if you have a number of other appliances such as a washing machine, drier, cooker all working at the same time. You definitely don't want that to happen, as it's not something you or a regular electrician can address.

Our DNO, UK Power Networks, came to see us and said they could put in an 80A fuse, since that would involve no external wiring change (our house supply comes from atop a wooden pole). However, I said I'd prefer a 100A capability, as that's the standard for most new builds, and give us oodles of capacity. UK Power Networks said no problem and arranged to come back a few weeks later. They replaced the incoming house cable with a thicker higher rated cable and fitted a 100A fuse. None of this cost us a penny.