Cunning plan for 'Water feature' lectric ..

Hi All,

A family friend bought a small 'Water feature' they want for the bottom of the garden and intended using the 240V power lead that comes with it and an extension lead and plugging it into a (std) socket in the car port.

I suggested this was all a bit 'naughty' and there were probably better / safer ways to do this?

So, my 'cunning plan' would be to fit a deep metal wall box into the wall just above the double socket (on a ring) in the conservatory (the decoration is easily repairable in there). This is also the nearest 'point' to where they want the water feature.

I was then going to drill from the back of the box, through the block / brick wall to the (silly as mentioned elsewhere on this n/g) 6" void between their and the neigbours extensions and fit (using my 90 deg drill solution ) a suitable waterproof (IP??) junction box and run some 2.5 mm T&E through conduit into the junction box.

I then thought of going from there in 3 core armoured (1.5mm?) down the fence to a waterproof (IP??) socket near the water feature some

10m away?

At the house end I was thinking of running a spur from the existing souble socket (I *might* be able to make it part of the ring but would I need / want to?) up a few inches to my new sunken metal box and through one of those +AKM-23 RCD's with rear outlet?

All my friends would see is the neat RCD, a glimpse of armoured behind the bushes and a working (and safe?) water feature? ;-)

I spotted in B&Q they do most of the above in the form of a pre assembled kit (I'd just need the RCD part), if it's all 'kosher' would this be cheaper than buying the bits separately (I think the kit was also on special at the time?).

All the best and thanks for your time in any case ..

T i m

p.s. Would it be ok to use the RCD as a 'switch' to turn the water feature on / off from the house end or should I also fit some form of (double pole) switch in there somewhere?

Reply to
T i m
Loading thread data ...

What you propose is certainly safer than running an extension lead down the garden. Unquestionably, you need the socket by the water feature to be RCD protected. If the ring in the conservatory is already so protected, you could rely on that when spurring off; it's almost better if it isn't, as in that case the 13A RCD fused spur you'll put in will be specific to the outdoor socket, rather than have the outdoor socket responsible, in the case of a fault (including damp, squirrels, etc.) cutting power to your video, PC, and the rest. (Hence 'best' being a dedicated fuseway in the CU for your outdoor socket - either using an RCBO there or the 13A RCD fused spur at/near the point of exit from the house.

In no way do you want to extend the ring out into the garden: pointless excursion of two cables, low current demand at the end point, overgreat current available, etc. etc.

Armoured cable in a deep trench is the very best way to run. Little worse is to run it, or SuperTuf/HiTuf if it's visible along its whole run (i.e. not going to be dug at) run above ground. IEE guidance says surface-run outdoor cable is OK clipped to a wall, but not a fence (too likely to topple in high winds); use your own judgement about the stability of the fence, and if you do decide to use it as support, leave some deliberate bendy slack at both ends to make it less likely that any fence collapse will leave live, bare wire poking out into the world ;-)

You suggested 1.5mmsq; it's harder to find SWA and HiTuf in such a small guage, and voltage-drop is in any case lower with 2.5mmsq (that's rated for 22A or so, so plenty of headroom). The switched fuse connection unit with built-in RCD I have in mind will allow you to fit a 3A or 13A fuse according to whether you want the socket at the far end to also be usable for mower, 1kW halogen worklamp, etc., or purely for the water pump, and will be a sensible means of isolation too (the switching you mention). Oh, if you use HiTuf, it'll be bendy enough that (especially if you take the route through the wall at a downward sloping angle) you can avoid any external junction box, using a single piece of unjointed cable from the load side of the RCD FCU to the external socket.

Where to buy? Try a 'real' electrical trade counter - even if you can't talk them into a discount the prices are likely to be comparable with B&Q, and they'll do you a cut length of the outdoor cable of just the right length (plus a bit over ;-) instead of you being bound by whatever precut lengths B&Q choose to sell. They'll also have all the glands and clips you need whether for armoured or HiTuf.

The choice of final socket is between pricey but very flexible MK Masterseal (about 15quid single, 25 double, at retail) which allows you to plug in ordinary 13A plugs and still have the connection sealed, or Clipsal "screwdown collar" 13A sockets (about 12 quid for a socket & plug combo). The latter is in fact a better seal for year-after-year use, and still lets you unplug the water feature for occasional use of other appliances. Whatever you choose (and it's harder still if the cheapie waterfeature has a plug-mounted transformer!) do take care to make sure it's reliably waterproofed. (Wrapping a trailing rubber socket in a carrier bag doesn't count...)

HTH - Stefek

Reply to
stefek.zaba

[T] I hoped it would be! ;-)

Unquestionably, you need the socket by the water feature to

[T] Understood .. I believe the CU has an RCD and it's likely the conservatory is hanging off that. I *could* come directly from the back of the CU (it's on an outside wall) but it would make the run to the bottom of the garden very long and akward.
[T] Sorry, I miss guided you here Stefek .. I meant I could pick a feed from the back of an existing socket on a ring as a spur, or I could include the RCD unit *into* the ring as it's only going to be a few inches away from the socket / pickup point?
[T] Interesting info and I thought I remembered similar from a long time back ..

use your own judgement about the stability of the fence,

[T] Understood. I will have to ask to see 1) Whose fence it is and 1) how it is errected (eg, if it's on met posts they will be pretty durable)?
[T] My mate with the Armoured gave me a 6" length this morning and I have it in my hand right now (no, don't go there, I'm not Gay or owt!). I have just trimmed back the sheath and not a couple of things .. 1) It seems to be three phase (rd / bl / ye)? Assuming I mark (sleeve) the cable accordingly can I use it (realistically) on single phase? (Red could be live, blue neutral (with black heatsrink sheath) and yellow earth (with green / yellow sheath?)? 2) From some crude measurements with a plastic vernier (the digital one is down the garage) is 2.5mm sq stuff

The switched fuse connection unit

[T] I think they have a battery mower .. I'll ask them what else they might want ..
[T] Understood, and nice and 'neat' .. if you are happy with 'HiTuf' ?
[T] The local trade counter offered me a double socket sized RCD at a 'special' price of +AKM-27 inc. B&Q do it for +AKM-23 (inc) (same item, not similar).

They'll also have all the glands and

[T] I noticed B&Q have *some* glands but not much in the way of a range .. (and often the bins are empty and mixed up ..)
[T] Again, thanks for the info ...

Whatever you choose (and it's harder still if

[T] Doh! I don't think *they* were even going to bother with the bag! I think there is a std (moulded) plug on the water feature but woth checking before we start anything ..
[T] Thanks very much for all your help and advice on this one mate ... It's all falling into place now ;-)

All the best ..

T i m

Reply to
T i m

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.