Replacing consumer unit in garage

[jamesgjatkin]

Hi all,
I have an old wire-type consumer unit in my garage.
There was some time back an addition of a small RCD+MCB unit for an external power to a pond.
I wish to replace both units with a single modern one with MCBs and an RCD.
I am planning to add the following:
- 1 x 6A for the lighting
- 1 x 16A for the sockets
- 1 x 6A for the pond feed.
- 1 x 40A 30mA RCD
- 1 x 63A Main Switch
There is a freezer powered from the sockets and also has occasional low power usage.
Does this look sufficient?
Any advice would be appreciated.
Regards,
James

 

[jamesgjatkin]

Much love , in the nicest possible way I didn't go to college for 4 years to tell you how to do it yourself

Apologies, I thought this was a discussion forum, not the Yellow Pages.

 

[Octopus]

Apologies, I thought this was a discussion forum, not the Yellow Pages.

Discussion forum for sparkies yes.

Giving step by step directions for DIYers - no.

Discuss.

 

[richy3333]

OK I held off in my last post...
Just because you are an engineer (I guess some sort of Bsc) that doesn't make you an electrician. I'm an engineer and know nothing about the aeronautical industry so I wouldn't try to build a space rocket. Just recently I've had to contend with the electrics in a hotel. The current owners had purchased it from an electrical/electronic engineer. It was a death trap. The guy knew nothing about BS7671 nor had any test equipment to ensure his work was safe. He didn't believe in certification of his own work either.

It would appear from what Murdoch said in an earlier post that you don't understand about the Building Regs, let alone worrying about the Wiring Regs.

Please get a competent sparky in to do the work (competent has special meaning in this instance if you refer to the Wiring Regs).

If your an engineer why not go on to the IET forum and talk to similarly minded engineers, they might give you a step by step reply? ANd don't forget to ask about exporting the earth

 

[dchester]

Thanks for all the answers...
When I moved into the house, it was the show house for the area.
This meant that they had run a direct feed to the garage consumer unit, i.e. not a spur from the house.
The pond feed has no sockets, it is a direct feed to a water proof external switch unit for the pump & UV.
My plan, as there are only 4 sockets and 4 ceiling lights, to do the following:
- Check the existing wiring and replace if necessary - I've never checked the quality of the wiring
- Replace the CU & RCD Unit with a single unit
- Carry out the final testing and get an electrician to certify it.
Does this sound like a sensible option or am I giving myself a world of hurt?
I do have a degree in Electrical & Electronic Engineering so I feel I am competent in the area.
My brother is also a professional electrical installations engineer so he is always a useful reference ;-)
James

I've no idea why those people are being so RUDE to you James. Your question is a perfectly reasonable and intelligent one. I am new to this forum and that kind of reaction from people makes me wonder if I actually want to be here!

It sounds to me like you have the right idea. You know you need to test thoroughly. You know that you need to have the work certified (presumably your brother will do this on his return).

I would say that as it's your garage you can get away without using a main switch as an RCD will do this job if you want to try to save a little money. Please correct me if I'm wrong someone, but provided it meets BS EN61008 it is certified for isolation and I'm pretty certain that would be OK.

I'd also recommend ensuring you use a CU with a spare slot for any unforseen future expansion.

As someone pointed out, don't forget to check the building regs.

Good luck!

David

 

[jamesgjatkin]

Hi David,

Firstly, thanks a lot for you reply. This is the sort of response I was hoping for yesterday. Much appreciated...
I have been pretty amazed, and at times insulted, by the responses I have had to what I considered a fairly straight forward question :-O

As far as comments from others regarding "Engineers" is concerned, that did make me laugh! Both myself and my brother have IEE accredited (at the time) degrees in Electrical & Electronic Engineering. During this process I opted to specialise more in the field of Electronics & Computing, and he continued on down the Electrician route. This does not mean that I did not spend several years accumulating a firm grasp of the fundamentals & principles, and have someone close by to clarify rules & regulations. As he is not around at the moment, I thought I'd throw out my ideas for others to comment on - I clearly won't be doing that again!

Thanks again David, and it is good to see that there is someone approachable that reads these forums.

Now, time for me to search how to delete this account...

 

[whitestu]

If you are reasonably intelligent and capable of reading you should be able to do the work in accordance with the current regs. Wiring a garage CU isn't exactly complicated. However the two key issues for me are:

1. Is it worth your time to buy and read the relevant books so you do the job according to 17th edition
2. The work is notifiable so do a) Ignore this at your risk or b) Pay for building control to inspect and approve.

If you are going to do 1 and 2b then you would have to ask yourself if might not cheaper to just pay an electrician to do the work for you?

I can see the point of some of the guys on here who are probably struggling to find work so feel a bit sour about telling you how to do stuff yourself.


Stu

 

[somersetsparks]

This forum sometimes reminds me of walking into a grub hut full of grumpy Scaffolders playing cards on your first day on site! lol.

Seriously though the chap seemed to be asking reasonably intelligent questions, and certainly didnt sound like a diy bodge it and scarperer did he?
I get the point about 'sparks have to pay for part p' etc. But at the end of the day its his garage he can do what he likes I think.
I think maybe we need to be a little more friendly

 

[marc_v33]

I've no idea why those people are being so RUDE to you James. Your question is a perfectly reasonable and intelligent one. I am new to this forum and that kind of reaction from people makes me wonder if I actually want to be here!


when i joined this forum years ago that was my first thought and rarely used it more recently i was stuck with a problem and logged back in. For me the knowlege from the guys on here is priceless but when they continually get diyer's etc etc looking to be told HOW to do a job for free thats whens its becomes a problem and folk get p@!?ed off at the same time i now know that if i do enconuter a problem and i prove in the information that i provide to the guys on here that i know what im talking i will be given an answer to my question! i guess you dont provided engineering information for free so why should we?.....

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[sparks1973]

just quickly scrolled through this....
1) no mention of earthing arrangements
2)no mention/enquiry of the C/U upstream feeding this (house C/U)
3)no mention of the supply cable to this garage (MICC, SWA) etc...
4)any extranious in the garage?
are there any spare ways at the upstream end?..if so, how many...

 

[Octopus]

People aren't being "so rude" they are just fed up with DIYer's coming here to sap knowledge and ignore the regs that we hard pressed sparks have to adhere to.

Shame this forum has so many rude DIYer's posting on it - whereas there is another one where sparkies help sparkies.

 

[D80]

Once did work for a retired engineer, most decent DIY'ers would do a lot better:banghead:

 

[marc_v33]

I was quoting from a previous post but didnt " quote " i agree with you murdoch

 

[not clever]

James you don't have to put up with rudeness. As Dan pointed out in other posts not long ago there are plenty of other electrician talk forums for you to visit for advice.

I hope I can go some way to helping with your DIY adventure.
As stated above the house supply earthing type is required as this will have a bearing on the possible requirement to RCD the supply to the garage.
The type of supply cable to the garage again will have possible implications on the requirement of an rcd at the supply end.

In the garage I would go with 30mA rcbo's for each circuit, might seem a little more expensive but will save the potential issue of a main switch rcd tripping, leaving you having a freezer full of food defrosting all because the pond pump gave up the ghost underwater.
Personally I would also go for utilizing a TT system on the garage consumer unit (if you don't know what or how to do this do a search on this or other UK electrician forums)
I would consider putting the freezer on it's own 16amp circuit.
Maybe move the pond pump circuit to the socket circuit via a switched fuse spur.

I have to add there is a fair bit involved with a cu swap (more than I have outlined above), including testing & certification. But lets face it your going to do the job anyway so try to do it right and safe & if that means asking on forums then crack on

 

[dchester]

when i joined this forum years ago that was my first thought and rarely used it more recently i was stuck with a problem and logged back in. For me the knowlege from the guys on here is priceless but when they continually get diyer's etc etc looking to be told HOW to do a job for free thats whens its becomes a problem and folk get p@!?ed off at the same time i now know that if i do enconuter a problem and i prove in the information that i provide to the guys on here that i know what im talking i will be given an answer to my question! i guess you dont provided engineering information for free so why should we?.....

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Does it actually hurt us to give DIYers some tips? This chap isn't taking away our business. He probably lives in a totally different part of the country. It's not like one of the sparks in here is likely to lose this bloke's business on account of being given some friendly advice. Why can't we just "be nice"?

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[steve_morrison]

Sorry if I've upset the grumpy gits & good bye as i may get booted for stating there are other forums out there that Talk about Electrics For all abilities even dare I say the diyers...

Maybe you need to get into Club 3000?