Outdoor Wiring for Pond

[MIH]

Having put in a pond over a year ago and with the oxygenating plant and other planting now well established, I wish to install an air pump initially so that I can get a few fish. This maybe be extended to UV device but not essential at the moment but I'd like to put a system in now that can be easily added to later.

Now I've read many topics on here already about the same subject and I'm aware of an outdoor kit that includes everything needed without requiring an electrician, etc. Having checked a few prices, it's apparent that I can easily reproduce the components of this kit by buying the individual items directly from TLC or similar.

This is list I have as follows:-


18m of 1.5mm 6943X 3 core SWA Steel Armoured Cable
2 x 2-Way Orange Above Ground Box Size 0
1 to 2m of 2.5mm 3 Core Rubber Flex Black
30 Amp Connector Strip
Weathersafe 4 Way Outdoor Power Box - IP65
SWA Gland to Compression Conversion Kit 0L
Pratley reducing shrouds
13 Amp MK Safety Plug - Charcoal
5 Amp Plug Fuse - BS1362

The connection at the house end is via the plug in an already installed waterproof socket which is on an RCD protected circuit.

Any comments, feedback or changes welcomed.

Many thanks.

 

[securespark]

This does away with the need for an electrician because?

 

[MIH]

As I will be doing the work myself.

 

[securespark]

You say you want to buy the equivalent of an outdoor kit because that would mean you would not need an electrician.

What I can't understand is why the list of materials you have posted means you would not need an electrician more than any other list of materials...

 

[ban-all-sheds]

Now I've read many topics on here already about the same subject and I'm aware of an outdoor kit that includes everything needed without requiring an electrician, etc. Having checked a few prices, it's apparent that I can easily reproduce the components of this kit by buying the individual items directly from TLC or similar.

This is list I have as follows:-


18m of 1.5mm 6943X 3 core SWA Steel Armoured Cable
2 x 2-Way Orange Above Ground Box Size 0
1 to 2m of 2.5mm 3 Core Rubber Flex Black
30 Amp Connector Strip
Weathersafe 4 Way Outdoor Power Box - IP65
SWA Gland to Compression Conversion Kit 0L
Pratley reducing shrouds
13 Amp MK Safety Plug - Charcoal
5 Amp Plug Fuse - BS1362

OK - fine.

Buy that lot and install it.

Not sure what your problem is/what you're asking.

 

[securespark]

How are you going to assemble the components?

 

[ericmark]

I think you may have read some old posts when in England (Still valid for Wales) unless you used a kit you needed to notify the LABC. Blagdon pumps made these kits to get around the Part P rules of the time as to notifying the LABC.

Although there is no change to the rules of what you have to do there is a change in notifying and the garden no longer is in the list of items requiring notification.

The main problem in the garden is water. Any enclosure which will naturally heat and cool will likely draw in water even when it should be water proof due to the air inside expanding and contracting. Replace that air with petroleum jelly and often there are no problems or mount boxes on fence posts, sheds etc so they can have a very small drain hole at bottom is another method. Much depends on your garden.

SWA cable needs a gland and there are different grades of gland right up to the Hawk gas tight but in the main it's where the gland enters the box where water gets in or the strain of the cable warps the box. It takes experience and skill to install a trouble free system.

I did all my joints in the shed or green house nothing was joined outside.

The outside electrics are the same as inside electrics in that protection is required both over current and earth leakage I see you are using a RCD plug with 5A fuse which should be ample however you should of course still calculate I think the ELI permitted for 5A BS1361 cartridge fuse for 0.4 seconds disconnection time is 8.36 ohms. I found this on internet as BS7671 only gives values for 3 and 13 amp.

Before you can calculate you need the ELI for socket used. Normally this would be less than 1.44 ohms but you really should measure it. 1.5mm² cable is around 0.029 ohms per meter to ensure the fuse will rupture under fault conditions you need to test or calculate. Electricians will normally test we have impedance meters which allow us to do it with ease but these are expensive around £75 to hire. The RCD also needs checking the test button only tests the mechanics you need a proper tester to find out how many milliseconds it takes. You are allowed 40 milliseconds at 5 times rated tripping current clearly not something one can do with a stop watch.

Although the Blagdon kit just plugged in with water resistance plugs and sockets this has been criticised as this also had not instructions as to limits of length and number of branches using a 5 meter extension lead or even a number of them plugged into each other is unlikely to cause danger but with 18 meters one really does have to follow the rules to ensure automatic disconnection in the event of a fault.

Clearly many DIY people cross their fingers and hope there is never a fault. But I would not want my grand children playing in garden unless I was certain if something goes wrong it will fail safe. I do not use RCD plugs as whole house is RCD protected and once a year I test the RCD's with a proper tester.

The problem with a RCD plug is power failures will cause them to trip so if you need the pumps running to protect the fish you have to manually reset an active RCD. You can as a socket get both active and passive RCD's but to use a passive you have to work out volt drop under fault conditions to ensure they will work. However getting a passive RCD socket fitted by some one with know how and test equipment may be a better option so pump will auto restart after a power cut.

 

[MIH]

Yes, ericmark, it's the Blagdon kits that I've seen and are still available but for the length of cable I'd need, the price seems to be close to £200.

Securespark, maybe it was my wording but it was these Blagdon kits that are marketed at home owners so that they can be installed by the homeowner without the need for an electrician. This is the kit I am trying to reproduce and fit myself.

Ban-all-sheds, I was hoping for some feedback on whether my research was right, acceptable or whatever. I've done some electrical work before and I'm no expert but I'm happy to try anything, the most recent being a fused spur into my conservatory that I also came to this site for advice, which you also kindly contributed to at the time.

 

[MIH]

Unfortunately I don't have the luxury of a shed etc. being close to the pond, in fact the shed is closer to the house than the pond so I'd have to make at least one connection externally.

The boxes I've been looking at are from Pratley and have built in glands for SWA cables, in fact the kit comes with everything you need to work with this type of cable including the shrouds. I can then get a conversion kit and reducers to fit rubber cable.

Just to clarify, the outdoor socket is on RCD protected circuit, the socket itself isn't an RCD socket.

Ericmark, I appreciate all the feedback, this is the kind of detail I was after so that I could make an informed decision as to whether I should continue with this myself or get an electrician involved.

I can see why a lot of people, just use an extension reel and a waterproof box to cover the reel and anything plugged into it.

 

[PrenticeBoyofDerry]

Although the work proposed here, is now not-notifiable in England, that does not mean that it is excluded from compliance to "part p". So with the necessity of an electrician now seemingly being not needed! It would then be down to the competence of the installer and their ability to comply to other requirements and the use of suitable materials and the making of good connections.

 

[MIH]

So with the necessity of an electrician now seemingly being not needed!

I didn't mean that we can all do without an electrician, I was specifically talking about the kit that can be easily source on the Internet. I was trying to replicate this kit as it can be done for half the price and do the work myself.

Given Ericmarks comments, it looks like I'll have to call in an electrical anyway due to the length of cable I require and to make sure the calculations are correct to make sure the setup is safe.