Distribution upgrade?

[macd2401]

The looped supply issue is one that's coming back to bite DNOs, big time. No doubt it seemed like a good idea at the time, 100A per house would sound ridiculous in the 1940/50/60s. Now we're having to throttle our usage because 100A sometimes isn't enough ?

 

[Alb]

It's only 23kW at unity pf so think car charger+electric shower+hob and oven and you are virtually there.
I can see greater need in the future for 3 phase domestic supplies as this would take you to 40kW at unity pf for a 100A line current. This would cope with the above plus an extra long term large load like a heat pump.
Talking of pf, I can also foresee a day when domestic consumers will be charged for low pf same as industry.

 

[Les burrows]

I'm about a decade behind you Les so I'm describing life in the 1960s.

That’s ok joe by that time most people had hot and cold running water telephones and probably 3 tv channels but the 60s mate they where the best years of my life bar none music, groups,bikes,and girls and then more girls yeh yeh yeh
Les

 

[Dodger]

You were all very lucky, we had no electricity in our cardboard box and sixteen of us lived in it on the side of a tip!

 

[jamesie]

You were all very lucky, we had no electricity in our cardboard box and sixteen of us lived in it on the side of a tip!

Luxury.....

 

[Coulomb]

W'n ahh w're a lud (pardon my fake British accent), we had to get up two hours before we went to bed to lick the road clean!

AND we enjoyed it! ?

 

[RichardC]

For our younger members who may have no idea what you are talking about.

 

[Fishettibean]

I was speaking to Western Power earlier in the year as my fuse carrier were marked as 60amp and asked to be upgraded to 100amp. They said they had a policy of only max 80amp on single phase. To get 100amp or more, a change to three phase is required at cost.
So engineer came out to upgrade the fuse to 80amp, and inside the 60amp fuse carrier, was 80amp fuse... ?
The engineer spend the most time calling HQ to not triggering the anti tamper notification on the smart meter that changing (or not in my case) the fuse.

 

[Spinynorman]

I was speaking to Western Power earlier in the year as my fuse carrier were marked as 60amp and asked to be upgraded to 100amp. They said they had a policy of only max 80amp on single phase. To get 100amp or more, a change to three phase is required at cost.
So engineer came out to upgrade the fuse to 80amp, and inside the 60amp fuse carrier, was 80amp fuse... ?
The engineer spend the most time calling HQ to not triggering the anti tamper notification on the smart meter that changing (or not in my case) the fuse.

Don’t see how that can be. I have a single phase unlooped supply with 100A fuse in it..? Perhaps it’s just different companies…

 

[Lovemyev]

It is my understanding that the DNO will only install a suitable size main protection fuse, that will suit the size ( load carrying capacity ) of the incoming supply cable to the property.
Just upgrading straight to a 100 amp fuse, on a supply cable that is not rated to allow this type of load through it, could be dangerous.
They are never going to upgrade the main fuse any where close to the limits of the carrying capacity of the supply cable.
The older the property, the more likely there is to be a restriction on the size of the fuse rating protecting the property.
Upgrading from a 60 Amp to a 80 Amp on a more modern day type of house, is not likely to be a major issue.
But wanting a 100Amp fuse installing, will require some further investigation work.
Will the meter tails need updating first etc etc.
My house was built in 1982 and is protected by a 60 Amp DNO fuse.
I have never requested a upgrade, you just have to be a little bit more considerate on what demand you place via that 60 Amp fuse.
I have charged my PHEV for almost five years before and now our BEV for the last 18 months, with no issues.
We are using a 7.0 kw wall box for our charging needs.

 

[Kithmo]

With Northern Power, I asked for an upgrade from my old 60A and they said the 80A would be free as it involves very little work and 100A would cost me. When they came, they had to dig up a small area of my drive to isolate the supply as I have no isolation switch, they did this, fitted a new fuse holder to replace the old bakelite one and fitted a new fuse. They then made good on the drive and left. When I checked the new holder it says, 100A on it so I assume they've fitted a 100A one for free. I was a bit puzzled as to why they didn't fit an isolator to make it easier for any future work but I guess that may be the responsibility of the supplier.

 

[Lovemyev]

With Northern Power, I asked for an upgrade from my old 60A and they said the 80A would be free as it involves very little work and 100A would cost me. When they came, they had to dig up a small area of my drive to isolate the supply as I have no isolation switch, they did this, fitted a new fuse holder to replace the old bakelite one and fitted a new fuse. They then made good on the drive and left. When I checked the new holder it says, 100A on it so I assume they've fitted a 100A one for free. I was a bit puzzled as to why they didn't fit an isolator to make it easier for any future work but I guess that may be the responsibility of the supplier.

They would need to dig up your drive, because they needed to replace the main fuse carrier head.
It’s the only way to isolate / interrupt the incoming feed to your house.
That main fuse head is constantly live on one side, even when the fuse is pulled !.
A typical set up goes a little like this.
You will have a heavy red or brown line ( live ) cable and a black / blue neutral cable leaving the DNO fuse head.
These are the meter tail cables.
These two separate meter tails, are then terminated at your electric meter.
Then another two meter tails, will go into the unswitched side of your optional 100 Amp isolation switch.
Then another two meter tails will leave the 100 Amp switch and be router to your consumer unit ( fuse box to many ).
When throwing this this double pole switch, it will isolate everything in the property, but more importantly, it will kill the supply to the consumer unit itself !.
Making working on the consumer unit safe without pulling the main DNO fuse ( which is the property of the DNO anyway, and should not be interfered with !.
After installing a 100 Amp DP switch, it should be sealed by either your electrical installer or the DNO - because one side of this switch is live all of the time !.

 

[Alb]

A standard fuseholder is rated at 100A but that doesn't necessarily mean a 100A fuse is fitted.
In my case I was told by Western Power that if they found a 60A fuse it would be uprated to 80A free of charge, but if I requested an uprate to 100A there would be a charge.
In the event they found a 100A already fitted and were happy to leave it. They were obviously content that the cable was adequately protected by 100A.

 

[SteveP]

I’m 63 and I remember every Sunday as a child when we sat down for our dinner my dad would put on our stereogram and we would listen to The Goon Show and The Clithero Kid those were the days hahaha

 

[Lovemyev]

A standard fuseholder is rated at 100A but that doesn't necessarily mean a 100A fuse is fitted.
In my case I was told by Western Power that if they found a 60A fuse it would be uprated to 80A free of charge, but if I requested an uprate to 100A there would be a charge.
In the event they found a 100A already fitted and were happy to leave it. They were obviously content that the cable was adequately protected by 100A.

For houses of a certain age, the meter tails where a little on the small size because it was not though that we would be charging cars on a 7.0kw wall box back then !.
A 60 Amp fuse was more than enough carrying capacity.
Upgrading from a 60 to a 80 Amp fuse and you COULD get away with your current meter tails.
When you ask for a 100 Amp upgrade, they need to check IF the incoming supply is capable of carrying that demand firstly and then check if the meter tails need upgrading.
And I feel they certainly would, unless your house is fairly new, in which case it would tend to be a 100 Amp carrier anyway.
A DNO fuse ratted at 100 Amps will in my opinion carry a higher load than 100 Amps for a short time due to safety margins.
But being totally honest, if I was pulling anything close to the fail condition of a 100 Amp fuse, then I would be more concerned about my next electricity bill !.
I am running on a 60 Amp DNO fuse BUT all of my meter tails have been upgraded by the EV installer.
He also installed a 100 Amp D/P isolation switch while the main fuse cartridge was pulled.
You just have to use a bit of common sense when using a lower ratted main fuse.
If you want to charge your car, at the same time as taking a wash in your electric shower, while cooking in your induction hob and having the washing machine and the tumble drier going !.
Then YES you are going to need a 100 Amp fuse and a large bank balance to pay the bill !.

 

[Lovemyev]

I’m 63 and I remember every Sunday as a child when we sat down for our dinner my dad would put on our stereogram and we would listen to The Goon Show and The Clithero Kid those were the days hahaha

The Goon Show !.
Prince Charles is a massive fan.
No comment !.

 

[Alb]

For houses of a certain age, the meter tails where a little on the small size because it was not though that we would be charging cars on a 7.0kw wall box back then !.
A 60 Amp fuse was more than enough carrying capacity.
Upgrading from a 60 to a 80 Amp fuse and you COULD get away with your current meter tails.
When you ask for a 100 Amp upgrade, they need to check IF the incoming supply is capable of carrying that demand firstly and then check if the meter tails need upgrading.
And I feel they certainly would, unless your house is fairly new, in which case it would tend to be a 100 Amp carrier anyway.
A DNO fuse ratted at 100 Amps will in my opinion carry a higher load than 100 Amps for a short time due to safety margins.
But being totally honest, if I was pulling anything close to the fail condition of a 100 Amp fuse, then I would be more concerned about my next electricity bill !.
I am running on a 60 Amp DNO fuse BUT all of my meter tails have been upgraded by the EV installer.
He also installed a 100 Amp D/P isolation switch while the main fuse cartridge was pulled.
You just have to use a bit of common sense when using a lower ratted main fuse.
If you want to charge your car, at the same time as taking a wash in your electric shower, while cooking in your induction hob and having the washing machine and the tumble drier going !.
Then YES you are going to need a 100 Amp fuse and a large bank balance to pay the bill !.

I should have added that my meter tails were uprated to 25mmSq when my smart meter was installed (I also had an isolator fitted at the same time).
The problem with a lower rated fuse (60A) is that you might easily find a transient condition where the rating was exceeded. As I had mentioned previously, think of car charger plus electric shower plus hob/oven simultaneously in use. That's not beyond the realms of possibility and the reason why some of the smarter chargers have fuse protection enabling them to back off on the charge rate when other domestic load is too high built into their functionality.

 

[Lovemyev]

I should have added that my meter tails were uprated to 25mmSq when my smart meter was installed (I also had an isolator fitted at the same time).
The problem with a lower rated fuse (60A) is that you might easily find a transient condition where the rating was exceeded. As I had mentioned previously, think of car charger plus electric shower plus hob/oven simultaneously in use. That's not beyond the realms of possibility and the reason why some of the smarter chargers have fuse protection enabling them to back off on the charge rate when other domestic load is too high built into their functionality.

Of course @Joe this is absolutely spot on information.
We have a 11.00 kw electric shower, but it is only there as a "Back Up" unit, because our main and regular shower unit is a power shower feed by our domestic hot water cylinder.
The internal pump is feed from switched spur carrying a small 5 Amp rated fuse.
We have a gas boiler and a duel fuel range cooker.
An automatic washing machine & drier ( No dish washer ).
Therefore, our biggest electrical demand is the EV wall box and nearly all of our charging is conducted over night on cheaper off rate rates, so then the demand on the supply is equally low.
Our EV installer just happened to be the owner of his own electrical business, with a vast knowledge and experience of both domestic and commercial electrical installations.
EV's is his new passion and he owned a Tesla model S at the time.
He did a personal appraisal of our property and our electrical usage case, and he offered some good sound advice regarding the load carrying capacity of our DNO fuse capacity.
He accompanied his EV installer and supervised the whole install and testing before leaving.
Of course, not everybody is lucky enough to get this type of personal help and advice.
Everybody's electrical system is going to totally different, no two cases are ever going to be the same.
What is okay for one property, is NOT going to be okay for the next !.
I am comfortable in the knowledge that I am not over stretching the load carrying capability of the 60 Amp DNO fuse in our usage case.

 

[Lovemyev]

Two of my neighbours with electric cars (one Tesla, one Mercedes) tell me they have to get their distribution upgraded (cabling from meter to street) to support their EV wallboxes. All our houses were built in the 1930s but I'm guessing the wiring that was replaced doesn't date back to then. Should I expect to do the same?

Here is good video on "Un-looping" a supply.
Worth a watch !.

 

[Archev]

We’ve been all electric for the last 20 odd years so we’ve scraped by on the original overhead supply cable for some time.
when we had problems with the line and ordered the MG at about the same time, it was decided to change to an underground supply. Our meter, fuses and tails were all upgraded. The driveway was dug up at the side of the house, the pavements and street were open for over a week to reach the power cable under the far side pavement. As it’s an busy A road with a fire station and frequent ambulances it was an interesting time. To add to the drama our gas supply was cancelled all those years ago and I had asked for it to be removed entirely. By chance the digger driver took extreme care and exposed the gas pipe at the side of the house. To be safe I asked the gas board to double check- yep - you guessed - the gas supply was still live - phew !! The Rolec charger was then installed.
What a lot of work - but we ended up with a very acceptable overall bill of £0.00
Just our perfect price ?