Quick question can you have an Rcd at both ends ie all garage or shed consumer units have a built in Rcd.
Not best practice as you will not achieve discrimination as to which will trip first in the event of a fault
now from off my head i don't have any Rcd on my house consumer unit.
If you have a TT supply you may want to rectify this as a mater of urgency.
So once i take feed from the back of an interior 2 gang switched socket then hole to outside of house once that's sealed up i can run straight up the garden or first run into a weather proof outside box then run up garden. Weather proof unit with or without built in Rcd.
You'll need an RCD as it isn't a distribution circuit (definitely if it's a TT supply, unless you can satisfy some other regs)
[SIZE=12pt]Choice 1. This is what i will be doing. Permanent power[/SIZE]
A. Take feed from rear of interior 2g sw. Skt with 2.5 mm 2 core armoured cable on a 32 m run up the garden to shed.
Hmm as it is coming off the socket circuit, can it be classed as a distribution circuit? I'd say no, so that them leads into you'll be spurring off a spur once you get into the shed so far better to put a fused spur (rcd fuse spur if no rcd at house cu on socket circuit) to the socket then swa from the spur to the shed.
Also I assume you'll be using the supply (socket) earth to gland the armour as the circuit extension cpc?
B. connect to gland then connect live/ neutral to RCD 2 way consumer unit with 6amp/ 16 amp mcb's
Ok, check the upstream rcd/no rcd, you may be able to bin the shed rcd.
C. Connect earth wire to earth rod/ clamp buried in garden - connect other end to brass tag on wire by consumer unit.
Rod enclosure?
Dependent on the house supply type will you be isolating the circuit extension swa armour from the TT system at the shed end?
D. Run 2.5 mm TWE to 2g sw skts x 3 daisy chained.
Called a radial circuit.
E. run 1.5 mm TWE to light switch then to light fittings that are daisy chained.
Ok
Am fully aware about Part p.
Spot on so you'll be aware that it needs testing & certificating the notifying
The reason why I'm going from the back of a socket in my back room is because I can't go straight from my house consumer unit as its under the stairs. Get a sparks in he may be able to offer a route that will enable you to use a larger csa swa, such as splitting the meter tails rather than going to the consumer unit.Hence coming off the back of a none used socket. is this ok.It doesn't matter if we say it's ok or not ok, your the one planning to do the design/installation/testing/certification & notificating ..... history tells us here if we say dont do it, most diyers bimble on regardless then post back when it's gone wrong or the rcd's keep tripping.
Firstly see my red above.
Let me tell you of my day on Sunday.
It starts last Wednesday I get a call
"I need a water heater putting in the garage/office, I put the electric in some months ago so that needs signing off as well" I agree to take a look.
I go there & yes it's a nice 2.5mm swa socket circuit extension from the back of a kitchen socket to the garage where it terminates into a 3036 board.
3036 board serves a 30amp ringmain with spurs off spurs & a lighting circuit consisting 6x 50w halogen & 2x 100w gls lamp posts.........the new water heater is a 9Kw unit.
I explain the swa is not suitable for the job & the installation method leads a lot to be desires & customer goes into panic as the consumer unit is under the stairs central of the house.
No problem I shall do it properly & split the meter tails in the external box.
"It's urgent & needs doing asap so the wife can start her beauty salon, she has customers pre booked for next week"
So sunday I:
Split meter tails.
put in a 100mA S type (TT system) & 50A mcb.
16mm 2 core swa down the drive to the garage.
new SBS cu with 20A ring / 6A lighting / 40A water heater.
new rod & enclosure.
Changed halogens for 9watt LED's
Nw 10mm circuit for water heater + switch for local isolation.
What I'm trying to say is there is a diy get by way & then there is the correct way, but for some reason diyers tend not to like being told.
