Electric supply to garage

[bussy]

Fuse a spare way in the house consumer unit to 30 amp, ensure the cable you run is thick enough for the supply needed in the workshop bearing in mind the distance involved and fit a second consumer unit in the workshop.

aha - this is what I'm interested in. WHen you say "fuse a spare way" do you simply mean finding a spare slot on the house consumer unit and plugging in a 30amp fuse then wiring back to that ?

Yes, that is what he means. But if you don't have one then panic ye not as what you will need are Henley blocks which are inserted between your meter and your existing consumer unit and then a new feed is also taken off from the Henley block(s) to - here I'm not too sure whether it's a fused switch or what but get your sparky involved - that feeds the cable to your workshop. Armoured cable can also be tricky/awkward to terminate and not something easily fitted into a plastic cased consumer unit without a lot of care (but it's been a while and I could be off the mark here).

Roger
How do you insert the blocks between the meter and consumer unit without removing the suppliers seals and pulling the service fuse (which is an offence) or do you advocate working live.

 

[RogerS]

aha - this is what I'm interested in. WHen you say "fuse a spare way" do you simply mean finding a spare slot on the house consumer unit and plugging in a 30amp fuse then wiring back to that ?

Yes, that is what he means. But if you don't have one then panic ye not as what you will need are Henley blocks which are inserted between your meter and your existing consumer unit and then a new feed is also taken off from the Henley block(s) to - here I'm not too sure whether it's a fused switch or what but get your sparky involved - that feeds the cable to your workshop. Armoured cable can also be tricky/awkward to terminate and not something easily fitted into a plastic cased consumer unit without a lot of care (but it's been a while and I could be off the mark here).

Roger
How do you insert the blocks between the meter and consumer unit without removing the suppliers seals and pulling the service fuse (which is an offence) or do you advocate working live.

I'd ask an electrician. If you have no spare ways in your consumer unit then this is the only route available to you. It is standard practice, I believe.

 

[bussy]

Hi Roger
In general electricians don't have authorisation from the distribution company to withdraw the service fuse, if they did they would have the offical pliers and seals. Thats not to say it doesn't happen. As you say your options are limited. Npower will fit a double pole isolator for you but it comes at a cost,

Marty

 

[n0legs]

I've never seen a problem with removing the seals on a cutout, as long as the meter reader can see work has been done that would require the mains to be switched off they are generally happy. Removing the seals on the meter is a different matter.
Working live is okay in my book also, I have done so for nearly 30 years. Rubber gloves are available for anyone to buy and the use of insulated tools is the norm for most involved with electrical work, follow a few simple rules and you are quite safe.

On the subject.
I quite often get on here with safety driven advice which to some may seem like I'm having a go, but today I'm going to give a little advice but in no way is this advice to be used as a "how to do it".
Each and every electrical installation needs proper design and correct installation.

The subject of supply cable and where to get the supply from is often one that comes up and causes many questions and some confusion.

I wouldn't bother looking for spare ways in the house consumer unit.
"I" would ask a qualified electrician to split the meter tails ( obviously after the meter or the electricity police will come knocking, shame though ! ) and terminate into a service block (also known as neutral blocks or Henley blocks).


Then using a suitable size cable, meter tails( pvc/pvc single core )

terminate into a fused main switch.

From this main switch take a suitably sized cable into a conversion box to make the change to a suitably sized armoured cable running to the workshop ( I'm writing this assuming the workshop is away from the house. With the armoured cable I would run a separate earth or use a 3 core cable so there is a proper earth conductor, I don't like or trust the steel wire armouring.
If you have a built in/on, integral garage type workshop then big T&E ( twin and earth ), cable could be used ).
At the workshop end using a metal consumer unit, this makes for an easy termination of the armoured cable.


Why ? Well in short it gives you the best options for capacity.
There is little point in going for a small supply, granted this is my own opinion.
Getting ever so slightly technical, about the biggest cable you can get into a domestic consumer unit is 10mm and that depends how neat the installation inside said consumer unit is, if you have an older consumer unit then 6mm can be a right pain, ( watch some smart a** come along and say they've done a 16mm T&E, yes yes been there got the t shirt, won't be repeating that again )

Let's take the main switch pictured above. In this switch you can fit a 60 amp fuse ( 80a is also available ) when used with the correct sized cables, run in the correct manner ( remember what I said about correct design and installation ) that's approx 13.8 Kw depending upon supply voltage. That's got to be enough for a home workshop ??

When it comes to system design, build in some redundancy or extra potential capacity. Why would you want to pay to have work done twice when you find you've hit the maximum load your installation can manage, when this happens people start taking chances ( trust me after nearly 30 years dealing with elastictrickery I've seen loads of risk takers and I bet there's a few on here ).
Short of having a full on separate supply to the workshop go as big as you can.

Like I said this isn't a "how to guide", it's just an indication of what you could have done and what you could ask a qualified person to install for you.

 

[bussy]

Hi n0legs
You may well be right about turning a blind eye with regards to missing cutout seals, I couldn't possibly confirm or deny, but at the end of the day it is an offence, my problem would be the fact that an unsealed cutout makes it easier for children to get in to it with potential fatal consequences, alright unlikely but possible, would you like to be the person responsible if that happened.
When we withdraw or replace services fuses in addition to insulated gloves it is mandatory to wear a full face visor, I've seen the damage an exploding service set can do to eyes and human flesh. paper insulated lead covered service cables can and do fail.
Just one point about the main switch you mention, being fused at 60A won't give you any discrimination from the service fuse, granted you would expect an rcd in the DB to trip before the main switch !!
Like you I'm not having a go just trying to give advice.

 

[n0legs]

Hi n0legs
You may well be right about turning a blind eye with regards to missing cutout seals, I couldn't possibly confirm or deny, but at the end of the day it is an offence, my problem would be the fact that an unsealed cutout makes it easier for children to get in to it with potential fatal consequences, alright unlikely but possible, would you like to be the person responsible if that happened.
When we withdraw or replace services fuses in addition to insulated gloves it is mandatory to wear a full face visor, I've seen the damage an exploding service set can do to eyes and human flesh. paper insulated lead covered service cables can and do fail.
Just one point about the main switch you mention, being fused at 60A won't give you any discrimination from the service fuse, granted you would expect an rcd in the DB to trip before the main switch !!
Like you I'm not having a go just trying to give advice.

Hi Bussy
I draw your attention to :-https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&cad=rja&uact=8&ved=0CFwQFjAF&url=https%3A%2F%2Fwww.ssepd.co.uk%2FWorkArea%2FDownloadAsset.aspx%3Fid%3D937&ei=D2tVVPngOoOs7Ab2poDICg&usg=AFQjCNGbhOfHrgSIBCKdXSympHXIV9Dzkg

I'm sorry the link is a bit long but I can't be bothered to scan my original.

I believe most DNO and suppliers have such guidelines and/or agreements, being the assumption that only qualified and or competent persons would be carrying out the works. This provision whether in writing or not has been one that has been afforded to contractors since as long as I was an apprentice cable jointer with South Wales Electricity Board in the '80s and have never heard of any professional being prosecuted for such action ( may be different in other area boards though and I stand to be corrected ). Besides, any decent electrician should/would re-seal the cutout as the availability of temporary seals and meter seals for private landlord meters has been around for a long long time.
I know all to well about cutouts, pilc cables etc and have been on the receiving end of a few flashovers and explosions myself. The wearing of the visor was a very good idea for cutout changes and metering work, but I believe the reason was due to a meter fixer trying to pull the fuse with a pair of pump grips, I'm sure you have been told as well as I was that if doesn't come out by hand then it was to be left for the mains staff to deal with either by shutdown or temporary isolation of the service cable.

You may have a point with the 60 amp fuse issue but I can't honestly remember the last time I installed one in a cutout or for that matter saw one. Our company got p***** off with callouts for no supplies due to fuse failure and instructed all to install 80 amp minimum.
Any way if the electrician is pulling the fuse to do as I suggested in my last post he could check the cutout fuse and then fuse his new gear to compensate as such. It's a matter of what is right at the time and as I said system design should be thorough.

Don't worry about having a go, I don't often see peoples comments as such, a discussion such as this is a good place for us to get some safe and proper advice down for others to read and follow, BUT NOT TO USE AS A HOW TO GUIDE.

Are you a meter fixer or on the mains ?

 

[bussy]

Good morning n0legs
Interesting document, in the Northern and Yorkshire areas (previously NEEB and YELB) there is no such arrangement I know contractors have in the past requested authority the withdraw fuse and have been turned down flat. We do install double pole isolators between the meter and customers DB (at a price), where this is not possible we will de-energise in the morning and re-energise in the afternoon again at a price. There was a meter that had an intergral isolator and split terminal cover to allow contractors to renew tails or work on the installation although this was never made available as the isolator was only single pole.

In general we fit 60A fuses on existing installations or 80A on new supplies, in fact a lot of existing fuse carriers in our area are limited to 60A (half cups). The DNO will put larger fuses in when called out for a no supply(excluding half cups). If working out of area we do follow the relevant DNO's fusing policy.

I am a meter installer (electric and gas) although started working life refurbishing calibrating and testing meters, then a few years on instrument repair. A spell in admin (sharp got tired of that) and now back on the tools.
Was hoping to get redundancy but smart meters have put paid to that, 6 million to install (not all by me) in our area.

 

[RogerS]

....... but smart meters have put paid to that, 6 million to install (not all by me) in our area.

Thank God, they're not a legal or mandatory requirement ! I, and many others, remain unconvinced about the security vulnerabilities, let alone the ability of the electricity supplier to switch you off (think computer ****-ups).

 

[n0legs]

Hi Bussy,
Interesting about lack of agreement up your way, but then there's a good earner involved for the electricity supplier. What's the cost for a DP isolator installation ?
I've seen the meters with the built in isolator, ( weren't they made by Sangamo ? ) and I agree with you the SP isolator was a waste of time. We went with a "meter pack" idea for new build with cutout, meters and a DP isolator already mounted. Brilliant idea to be honest although a lot of the boys didn't like fitting them as " they're too heavy ", wimps.
Oh !! fusing policies, that for us turned into a right issue ( pounds, pounds, ££££, callout, callout, callout ) you get my drift.
Smart meters, don't know about them and not sure if I need or want to know more. Rogers comments are something I heard a few times already, but what I do know it's bad for jobs and without the meter men you could be losing a valuable asset with regards to safety and security of the system.

 

[bussy]

Roger
They may not be legal or mandatory but will the suppliers charge a premium for people not having them fitted because of the increased cost of having to read your meter manually. As far as security is concerned I don't really know, we are still in the trial mode at present and only a few of our installers have been trained, as far as I'm aware they are sim card based, and as we all know mobiles can be hacked, I don't know. Remote disconnection would be very problematic for suppliers as they wouldn't know if there were vunerable people on site ie young children or elderly people with medical equipment ect, and they certainly couldn't re-energise remotely.

N0legs
They were Samsung meters. An isolator is around the £100 mark for one offs there is a discount for block orders ie councils, housing associations etc.
The meter pack seems like a good idea, never heard of them. Wouldn't it be a good idea if all the suppliers and DNO's got together and shared good ideas and bests practices, personally I think we would all be better of if the utility sectors were returned to the people who paid for the infrastructure in the first place, when it was owned by the people it may have been over staffed and not as efficient as it could have been, but it worked.

 

[n0legs]

N0legs
personally I think we would all be better of if the utility sectors were returned to the people who paid for the infrastructure in the first place, when it was owned by the people it may have been over staffed and not as efficient as it could have been, but it worked.

Now you're talking.
I'll be honest I did very well with the free shares and the share save scheme we had, but I wish it could go back to way old ways. No one has won anything from privatisation of water, gas, electricity except for the "fat cats".
The savings to customers due to the deregulation have never truly appeared, too many people with to much input have been allowed in, bean counters having the final say on investment and reinforcement of the system,,,,, in short it's gone to hell in a hand cart.
What are we 20 odd years in and I still get confused customers not knowing who to call when there's power cuts. To be honest when you've met an old lady who's sat in the dark, freezing cold because no one she has spoke too can help her out, or has confused her even more, you soon learn the idea was a bad one.

 

[RogerS]

I think it depends on who your supplier is. We used to be with MEB and they weren't that good. After several changes of owner, we are now with Western Power and they are brilliant. At least that is who we ring up when there is an outage.

This is an interesting study on smart meters http://www.cl.cam.ac.uk/~rja14/Papers/JSAC-draft.pdf

and here http://www.cl.cam.ac.uk/~rja14/Papers/m ... switch.pdf

 

[topchippyles]

easy to sort-run workshop on its own ring main with a four way consumer unit with a 40amp supply from house to workshop,get electrician to put feed from house into workshop and install new consumer unit and sign off with part p,then run your own lighting ring and socket ring,will take 2no trips leaving 2 more to hard wire mashines direct,my joinery shop is run that way and 40amp will run a 25hp 3 phase inverter which i run my shop on with 3 phase mashines if you ever upgraded to hope this helps cheers les