Garage Electrics

[HDPete]

Hi all - long time lurker, first time poster.

I have just had a new garage built to replace an old one. The electrics from the old garage were delivered by a spur off of the house upstairs ring main.

I intend to retain that spur, but it will be connected to a new consumber unit (40A RCD with 16A MCD). I want to run 10x Double sockets from that consumer unit.

Whilst this may not adhere to regulations, is it acceptable and safe to do this? Would the configuration be a ring within the garage, or would each double socket simply be a spur of the previous one and so on?

Thanks in advance!
Pete

 

[ban-all-sheds]

I intend to retain that spur, but it will be connected to a new consumber unit (40A RCD with 16A MCD).

Why? Is the house circuit not RCD protected?

I want to run 10x Double sockets from that consumer unit.

No lights?

What will you be plugging into the sockets?

Whilst this may not adhere to regulations

Why would you consider doing something that contravened the regulations? Talking of which, you do know that this is notifiable, don't you...

is it acceptable and safe to do this?

What sort of cable goes to the garage?
What size is it?
How does it get there?
How long is it?
Does it come from an FCU on the house circuit, or just a junction box or socket?

Would the configuration be a ring within the garage,

Not much point.

or would each double socket simply be a spur of the previous one and so on?

That's a radial circuit.

 

[HDPete]

Thanks for the very prompt response!!

The house is RCD protected already, but the CU comes with a 40A RCD and 2xMCD's. 1x is for lighting at 6A and 1x for sockets at 16A. I've got the lighting covered.

Is there a problem with having another RCD?

The garage is fed (~3m) from the house via steel conduit at roof level with 4mm cable. This is connected to the Ring via a juntion box in the loft. I don't believe that it is an FCU. The radial circuit would be wired with 2.5mm Twin & Earth (new colours).

The sockets will not all have a load connected - it is to provide scalability if I add more equipment. The garage is to be used as an office and will have a couple of PCs connected; possibly a UPS.

Cheers,
Pete.

 

[Adam_151]

Two identical RCDs in series is rather pointless, you may as well toss a 50p piece to decide which one will operate!

branching an unfused 4mm² off a ring final carries the risk of unbalenceing the ring final, and definatly isn't a standard arrangement, this feed to the garage would be better moved off the rfc and made into a proper submain from the main DB

devils advocate now... if the garage is to be used as an office and no one really knows how much IT kit is going to end up in there eventually... perhaps we should also be considering section 607....

 

[ColJack]

BAS.. you sure it's notifiable?

Adam, while I agree that it's better run back to the CU on it's own breaker, I'd rather see a spur taken off a ring in 4mm than 2.5mm..

it becomes a fused spur due to the fact that it goes through a new CU.. albeit a 22A one ( 16A + 6A.. )..

a ring would be better given that it's going to be used for lots of IT equipment and you must use dual earth sockets, one earth in each terminal, and put the earths in different screws in the mini CU..

 

[ban-all-sheds]

BAS.. you sure it's notifiable?

Read Schedule 2B and tell me how it qualifies as non-notifiable..

 

[ban-all-sheds]

The garage is fed (~3m) from the house via steel conduit

Is it heavy gauge conduit, at least 20mm dia, with no joints, and is it earthed?

at roof level

Is "roof level" at least 3m from the ground, or 5.2m if vehicles can drive under it?

 

[ColJack]

i wasn't thinking of it in terms of a new CU since it's a sub board..

I was thinking that it's not in a special location..
it's adding extra sockets to an existing circuit...

if he misses out the CU and puts the sockets into the existing ring with 2x2.5mm and uses a fused spur to feed the lights then it doesn't need notifying does it?

I do enjoy these little debates with you BAS.. it's most informative most of the time..

I thought that you'd left the forums though.. only came back to ask a few questions..?

 

[Deluks]

I thought that you'd left the forums though.. only came back to ask a few questions..?

He's always been here, under an assumed name

 

[Steve69torpedo]

You dont even have to notify any works. Who's gonna find out??????

Sorry, better watch as you may be imprisoned for life cause you added a couple of sockets!!!

 

[ban-all-sheds]

if he misses out the CU and puts the sockets into the existing ring with 2x2.5mm and uses a fused spur to feed the lights then it doesn't need notifying does it?

Probably not - certainly doubtful enough for it to be a reasonable interpretation.

I thought that you'd left the forums though.. only came back to ask a few questions..?

Yup, and I though that as I was doing that I'd contribute. My questions are about done for now, so I keep thinking I should disengage, and not start contributing to anything new. I'm subscribed to everything I've touched, so if anybody follows up I'll be notified.

 

[ban-all-sheds]

I thought that you'd left the forums though.. only came back to ask a few questions..?

He's always been here, under an assumed name

Not true.

 

[ban-all-sheds]

You dont even have to notify any works. Who's gonna find out??????

Nothing wrong with giving an opinion on how likely that is, and giving people informaton so that they themselves can make an informed decision about what to do, but I'm not sure you should actually advise people to break the law...

 

[mdbalson]

You dont even have to notify any works. Who's gonna find out??????

Nothing wrong with giving an opinion on how likely that is, and giving people informaton so that they themselves can make an informed decision about what to do, but I'm not sure you should actually advise people to break the law...

Any way "Steve69torpedo" electrical topics have got to be wind ups (i.e. "Moving my service head" & his "earth rod" topic)


And that last post of his on this topic is very poor advice, advising people to break the law