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Wardie

Hi guys, I've just been given a date for EDF to come and connect 3-phase supply to my garage at home (I'm starting my own business and unfortunately the control cabinet I'm designing needs 415v 3p, so to hold off renting a unit I thought I'd power-up and test the machine at home).

I've sourced a distribution board etc. but obviously need it wired, I would do this myself but don't want to break any laws!! In order to keep costs down I thought I'd fit all sockets/cables etc. then get a qualified person to do all the connecting and testing. (Do sparks hate it when people try to 'get involved' like that?)

What's the best wiring practices? Is it best to wire the 3p runs in swa...god I hate working with that stuff!, or can I use something else run in metal/plastic conduit/trunking?
As my garage wasn't wired at all when the house was built I'll put a couple of 240v ring mains in too, is it best to put that in the same conduit/trunking?

Sorry if these questions are a bit stupid, I'm just trying to do the right thing but by spending the smallest amount of money possible!

Thanks, oh great forum by the way!
 
Hello there and welcome to the forum.

(Do sparks hate it when people try to 'get involved' like that?)
What sparks do not like is people hiding dodgy work and trying to get the spark to sign it of. If the spark can see all of your cable routing and check all terminations and joints, i cant see a problem.

As this work is in a domestic dwelling and involves in affect a complete new power distribution system, it would be notifiable to the local council.

My advise would be to contact a 3 local electricians, explain to them what you want to do and the work you are willing to undertake and see how much they want. They will advise on the correct type of cable/trunking ect,ect,ect.
 
An interesting one this.

If the garage is integral to the house realistically it can be classed as requiring Part P certification, however if the garage is seperate from the house and it is being registered for business use it would not be classed as a dwelling. If it is registered for business use then it will have seperate rates applied to it and may require planning permission for change of useage. Also if it is registered for business use the existing final rings circuits should be removed as they are (I assume) being fed from the domestic consumer unit.

What certification is required is dependant upon what you have done regarding the official useage of the garage.

Think how you want to play things and once that is decided upon it can be taken from there.

Not meaning to be offensive but you may find difficulty in getting an electrician to do the the mains connections and then certify the entire installation as several of the electrical organisations advise their members not to issue installation certificates where they have not done the installation.

Good luck with your business.
 
Thanks for your input guys.

spark-doctor: I phoned the local council planning dept. who put me through to building control. They said if it gets signed off by someone with part P then they don't need to know, if I don't then they'll need to come and test.

tony: The garage isn't attached to the house and there's no power in there at all. Regarding registering it as a business I was unsure what to do there, I'm looking at it as a private/home installation. I didn't want to get into change of use and all that, my view on it is that I won't actually be manufacturing or running the business from there, it's just somewhere I can power-up and fault-find the wiring to the plc, servos and drives etc.
I'm looking at registering the business in the new year, I should have a unit sorted by then.

EDF are installing upto and including the fuse (by the sound of it) in a couple of weeks time, then they're coming out the next day to put the meter in. They said that the distribution board will have to be installed by then so they can connect the tails.
If I can't get the garage wired by then, do I need part P to screw the db to the wall and leave tails hanging?
 
Changing or fitting a new distribution board in a domestic property is notifiable work so you would need to either get a registered spark to fit it or notify building control.

If you get a spark who is a member of a competent person scheme they will test everything after it is all fitted and will notify building control through there scheme provider and then the LABC will issue you with a certificate.

You can have the DB fitted and then wired at a later date but check that the spark that you use is happy with the route you take or you could ask EDF to install the tails into Henley blocks so your spark can connect at a later date.
 
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Can we bounce this one round a bit.

I was under the impression that Part P applied to "Electrical Safety - Dwellings" in which case would the installation of a three phase supply into a detached garage require Part P as the garage is not a dwelling.

If the supply were to be installed in the house, to feed the garage then I can see that it would be required, but in this case?

What do the rest of you think, this is one I would like to know the answer to for my own information as much as anything. :confused:
 
I'm glad it's not just me who wondered about the part P side of things, I too went through the whole dilemma of whether this falls within part P or not, but not being 'in the know' I just thought it's better to be safe than sorry!
I did ask the lady from building control but she admitted that she didn't have a clue what I was talking about, she just said get the work carried out by someone with part P or get a building control inspection done when complete.
 
I did ask the lady from building control but she admitted that she didn't have a clue what I was talking about, she just said get the work carried out by someone with part P or get a building control inspection done when complete.

Hi Wardie

First off, no need to apologise, this is what the forum is all about discussing topics and helping where we can.
The last bit of your thread (quoted above) leads me to think that you really need to get Part P because this is what your building control have told you.

Spark Doctor

I agree, it does not matter whether it is three phase or single phase in a house it will need Part P. The thing that has got me thinking is does a detached garage, being on the land of a residential property, require Part P approval for its own electrical supply. Part P actually applies to individual "dwellings", so would a garage constitute a dwelling when the house is on the same land. If you think of a farm the farmhouse will require Part P, as it is the "dwelling" whereas the outbuildings will not.
Could a garage, in this type of circumstance, fall under the same categorisation as the outbuildings?

I'm still thinking (and it hurts)

Tony
 
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Local councils, you got to love them.

Ha ha, I'm learning to love them!

I have to admit that the line in page 5 seems pretty clear to me now: "Part P applies also to parts of...electrical installations; in outbuildings such as sheds, detached garages and greenhouses."

Is 415v classed as "...low or extra-low voltage..."?

Tony, I did just get the impression that she was saying the Part P thing as that's all she knows to say, she didn't seem very well informed...no disrespect to her.
 
I believe (please correct me if i am wrong) that this comes under "The construction and use regulations".

In a domestic dwelling, any thing that is within the footprint of the property is within the regulations but in a farm the house would be under part P but if the out building were to be part of the farm then they would be commercial and not under the scope of part P.

Similarly if you have a pub with a flat above and they share a power supply then both come under part P but if they have separate supplies then the pub would not and the flat would.

Please note that this is not a excuse to put 5 chickens and a pig in your garage and claim that it is for commercial use.
 
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So it goes back to my first entry, that if a change of use were applied for and the garage registered for business use then Part P would not be applicable.

One day someone will just say to us electricians, "This is what you MUST do" and it will make sense and not contradict something else and we will all collapse with shock (non electrical type)

---Note to self (in best Bane manner) Must stop thinking!!!
 
Low voltage is below 1000v and above 50v AC

Extra low voltage is below 50v AC

So it goes back to my first entry, that if a change of use were applied for and the garage registered for business use then Part P would not be applicable.

One day someone will just say to us electricians, "This is what you MUST do" and it will make sense and not contradict something else and we will all collapse with shock (non electrical type)

---Note to self (in best Bane manner) Must stop thinking!!!

That about sums it up.

Note. Never stop thinking. If you stop thinking, you stop learning:D
 
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Ha ha, I'm learning to love them!
...I did just get the impression that she was saying the Part P thing as that's all she knows to say, she didn't seem very well informed...no disrespect to her.

http://www.electriciansforums.net/business-related/1793-local-grant-funding-post13384.html#post13384


How y' doin' Wardie, as you can see I don't have much admiration for the wonks who dream these schemes and assume we all need to have our hands held. I'll say no more.

I had 3ph installed to run my scuba cylinder compressor adjacent to the shop and it cost me a packet for them to run all of 6 yards from the street service cable and a week later a series of almighty thumps under the paving outside were felt through the floor accompanied by the vaporous smell of boiling soil coming up through the floorboards as the new cable faulted between phases. 'kin apes! but how's this for a poss lateral solution?
What's the actual 3ph capacity required? Your building control cabs yes? you don't need to apply full loads to them just confirm operation of plc's and control gear. How about generating a local 3ph source from a single phase supply of sufficient capacity for you satisfactorily to test the units using an invertor/drive of suitable rating? Would that be easier or do you really need that 4c x 25mm or whatever?
 
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One day someone will just say to us electricians, "This is what you MUST do" and it will make sense and not contradict something else and we will all collapse with shock (non electrical type)

Doubt they'll tell you what you MUST do as they'll then be accountable, better for them to state 'grey' regulations and let you lot interperate it anyway you can. They then earn the money and are never held accountable! Oh what a glorious position!

Low voltage is below 1000v and above 50v AC

Extra low voltage is below 50v AC

Oh I see, forgive me, I'm used to working with mV, so that's what I call extra low voltage and 24v is low! :D

What's the actual 3ph capacity required? Your building control cabs yes? you don't need to apply full loads to them just confirm operation of plc's and control gear. How about generating a local 3ph source from a single phase supply of sufficient capacity for you satisfactorily to test the units using an invertor/drive of suitable rating? Would that be easier or do you really need that 4c x 25mm or whatever?

Hi Carter, Yeah I'm only building the 1 cabinet, for my prototype machine. I'm setting up a manufacturing company but I just want to get the first machine built and sequencing (which may take at least a couple of months) before I move into a unit. I'm just trying to stem the flow of outlay a bit at the moment!
I did think about generating local 3ph from a single phase supply but as I didn't have a single phase supply to the garage anyway the costs and hassle of doing all the work to get single phase in there, then getting the necessary equipment would've ended up about the same if not more. EDF are charging just under £1200 to make the connection under the pavement at the bottom of my garden, I dug the 4m long trench and laid the ducting etc. and even screwed the board to the wall in the garage ready for the meter...at their request (I think I'm in the wrong job!).

I'd like to be able to fit the single phase rings and 3ph runs round the garage then get a spark to make the connections and issue the cert. I just wasn't sure what to do it all in, swa or conduit/trunking. I'm not trying to cut corners or anything like that I just thought it would save a lot of the sparks time and therefore my money!
 
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Yeah Carter I'm liking the look of the genny!
Really should've given something like that a bit of thought, I got so caught up with getting any sort of supply into the garage I didn't even stop to think about a generator :(

I've spent too much already to go back now :eek:

Still, I may be able to justify one somehow...
 

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