[Question] Unprotected buried cable for garden lights?

[seven+]

Hello!

I'm hoping someone can please shed some light on this ('cuse the pun). I am not an electrician but I hope I am allowed to post this here?

The house we bought has 5 of these garden lights along the walls (inside our boundary):



They are powered off an outdoor plug socket which runs a cable to them that is simply buried in the ground along the walls (which are garden beds), not in conduit.

The cable says the following on it "Aberdare cables GBU1 300/500V Sans 1507"

and looks like this:




1) Is it legal to have this cable running unprotected in the ground? It seems really dodgy having this cable unprotected in garden beds.

2) I need to run an irrigation valve control cable (8 core comms cable) along the same route as the lights cable and will probably put it in a conduit, so I thought I should maybe try to run the lights cable in same conduit. Is this legal & may I do it myself?

I was thinking of running the conduit up to the underside of each light & then down again to continue to the next one if that makes sense.

Thanks for the help!

[AndyD]

Ironically the burying of that particular cable isn't against the regs but using it as trailing cable and fitting it into a plug is. That cable is known as surfix and it can be installed without additional containment such as conduit or trunking. I'm not sure about the white PVC, some white PVC cables aren't UV stabilised and can't be installed anywhere where they'd get direct sunlight, usually the black PVC cable is good for UV/sunlight but you'd have to confirm with Aberdaire because I can't see anything about UV stability on their website..

You shouldn't mix electrical circuit cabling and irrigation valve control cables in the same containment, they should each be in their own conduits.

**edit** if the neutral and earth wires come into contact in that plug you'll have an earth leakage tripping fault that will keep tripping even when the circuit breaker supplying that circuit is in the off position.

[bergie]

if i did a CoC on that installation i would fail it on a few points. the surfix cables are " not suitably bushed". if there are no glands then the cable should be chased into the wall. surfix has to be buried a minimum depth . if its not in a pipe then there must be danger tape above it. as andy said the cable cant just be plugged in. i think white surfix cable is UV resistant. i phoned the manufacturer a few years back to confirm.

[RegElec]

Surfix can be buried directly in the ground and as it has 'metal stiffening' and in this case has earth leakage protection I dont believe any danger tape is required. I agree with bergie that these days the white and black surfix has UV protection.
Andy, on the point of not being able to plug it in can you provide the regs .

[Eskom]

6.14.1.6 In a lighting circuit, a luminaire may be fed from a socket-outlet on a wall (that may be unswitched), provided that the socket-outlet a) complies with SANS 164-3, b) is protected by earth leakage protection, Amdt 5 c) supplies one luminaire only, not exceeding the rating of the socket outlet, and d) is within 3 m of the luminaire that it supplies

Also the socket oulet outside should be suitably protecteg against weather. Hope it is

[MullerR]

Ironically the burying of that particular cable isn't against the regs but using it as trailing cable and fitting it into a plug is.

Andy can you please give more information on this quote? What regulation states that it is not allowed to be fitted into a plug?



According to Aberdare Catalog both the white and black surfix are UV Protected.
For interest sake, check the note on the picture.
Reg. 6.3.6.1 The cables may be installed
(h)under screed if protected by an earth leakage protection device with a
rated earth leakage tripping current (rated residual current) IΔn not
exceeding 30 mA.

Reg. 6.3.6.2 These cables shall not be buried direct in concrete.

I understand why concrete, but why according to supplier it shall not be buried in screed if it is allowed by the Regs?

[bergie]

6.14.1.6 In a lighting circuit, a luminaire may be fed from a socket-outlet on a wall (that may be unswitched), provided that the socket-outlet a) complies with SANS 164-3, b) is protected by earth leakage protection, Amdt 5 c) supplies one luminaire only, not exceeding the rating of the socket outlet, and d) is within 3 m of the luminaire that it supplies

Also the socket oulet outside should be suitably protecteg against weather. Hope it is

so it can be plugged in , but each light on its own plug . definite fail of that installation

[seven+]

Thank you everyone for the input so far, much appreciated, you guys are great!

Unfortunately I will have to treat the remedial work on these lights as a separate [to my irrigation] project (when I have funds/time!!) so for now I will leave them unplugged (I was hoping it would be a case of killing 2 birds with 1 stone).

On a related note, I was sold the same type of cable (different manufacturer) by my local electrical wholesaler (Plumstead Electrical) to use to wire the wellpoint pump to an outdoor plug socket outlet (in a weatherbox) but given the comments already I am now wondering if this is compliant?

Secondly, I already ran the pump's cable (about 6m) in a single 20mm conduit together with irrigation valve comms cable (the comms cable I referred to in my original post is for a second set of valves located elsewhere in the garden), but from AndyD's comment I understand that this is not compliant and I must run the pump's power cable and the comms cable in separate conduits?

Thank you for all the help!!

[AndyD]

Good to know that the white surfix is also UV rated PVC.

...Andy can you please give more information on this quote? What regulation states that it is not allowed to be fitted into a plug?.....

Best I can do for a reg at short notice would be;
6.4.3.3 A cable shall not be bent more than is recommended by the cable manufacturer.

A cable trailing from a plug would need to be what's referred to in the regs as a 'flexible cord' and as such would need to qualify to this;
3.9.3
flexible cord
cable of which
a) the nominal cross-sectional area of each conductor does not exceed
4 mm˛, and
b) each conductor consists of strands of diameter less than 0,31 mm

My line of thinking in making the statement was that trailing cables such as cabtyre or HO5/HO7 etc are stranded conductors and designed to be sufficiently flexible to accomodate constant bending when hanging free/unsecured from a plug. Surfix on the other hand has solid conductors and would IMHO be totally unsuitable for termination into a plug. There's also an issue whether the terminations on the plug pins are rated as suitable for solid conductors and whether the cable clamp on the plug is suitable for cables with stiffening in the sheath.

[MullerR]

6.4.3.3 A cable shall not be bent more than is recommended by the cable manufacturer.[/I]

A cable trailing from a plug would need to be what's referred to in the regs as a 'flexible cord' and as such would need to qualify to this;
3.9.3
flexible cord
cable of which
a) the nominal cross-sectional area of each conductor does not exceed
4 mm˛, and
b) each conductor consists of strands of diameter less than 0,31 mm

My line of thinking in making the statement was that trailing cables such as cabtyre or HO5/HO7 etc are stranded conductors and designed to be sufficiently flexible to accomodate constant bending when hanging free/unsecured from a plug. Surfix on the other hand has solid conductors and would IMHO be totally unsuitable for termination into a plug. There's also an issue whether the terminations on the plug pins are rated as suitable for solid conductors and whether the cable clamp on the plug is suitable for cables with stiffening in the sheath.

Never looked at it that way, but now mentioning it, it makes sense. Always a good idea to hear other peoples opinions and see the regs from another point of view. Thanx a lot for that one Andy.

[RegElec]

6.14.1.6 In a lighting circuit - I think that reg is referring to a fixed supply into the socket outlet that supplies lights.

[Tang]

Hi. So if that was 2.5mm surfix connected directly in the plug (using the switch for the lights and the socket unswitched) ,buried at the right depth. What would the issues be?