How Deep

[Bez]

Afternoon chaps, I am soon to be installing some garden lighting, (amongst other things), and will be using 1.5mm Armoured. My BRB is away at a mates at the moment and can't find reference in the OSG as to how deep to bury the cable. 600mm sticks in my mind for some reason, with warning tape at 450mm. I'm probably imagining it but would be grateful if someone could verify for me.

Cheers

Bez

 

[Lurch]

Doesn;t sound a bad plan. There isn't an actual regulation specifying depth anymore, it's down to the installer to bury the cable to a suitable depth depending of the likelihood of it being damaged.

If it's in someones back garden then as a guide a decent spade depth plus a bit for good measure, with warning tape above.

 

[spinlondon]

Don't forget the layer of soft sand under and around the cable, to protect it from stones and rocks.

 

[Bez]

Don't forget the layer of soft sand under and around the cable, to protect it from stones and rocks.

Is that necessary with armoured cable?

 

[Lurch]

Is that necessary with armoured cable?

Yes. Even though it's armoured it can still be deformed by being jammed against a rock or stone and therefore cause low IR issues.

 

[Bez]

Gotcha, many thanks guys. Something else I've learned today

 

[androiduk2002]

Gotcha, many thanks guys. Something else I've learned today

That makes 2 of us

 

[Lurch]

That's what it's all about.

 

[Robojin]

Afternoon chaps, I am soon to be installing some garden lighting, (amongst other things), and will be using 1.5mm Armoured. My BRB is away at a mates at the moment and can't find reference in the OSG as to how deep to bury the cable. 600mm sticks in my mind for some reason, with warning tape at 450mm. I'm probably imagining it but would be grateful if someone could verify for me.Cheers

Bez

As I recall it's 600mm, on pea gravel bed (for drainage), gravel filler just over SWA, concrete capping (such as brick wall capping), hazard tape and then backfilled

Maybe some will feel it's OTT but that's the way is now it seems

 

[a1]

Thought it was 600mm from the surface to the top of the cable if buried across a roadway etc.

And 450mm from the surface to the top of the cable if it is in a private garden? :|

either way - Warning marker tape 150mm above the cable.

 

[ianmacd]

I thought it was in a bit of old hose pipe after watching Charlie Dimmock all those years doing water features on Ground Force .

 

[M107]

I was taught that the sand apart from the stones senario already mentioned, is put into the base of the trench to level out any dips. If the dip's were left & the trench were backfilled the cable will become streched (thats why the cable is also snaked in the base of the trench, to give a little slack).......the more dips the tighter the cable becomes.

 

[Bez]

Blimey, it's turning into a landscaping job:O

 

[Lurch]

Thought it was 600mm from the surface to the top of the cable if buried across a roadway etc.

That would depend who owns the road.

 

[a1]

Sorry Lurch, I meant to add "Council" to that.

 

[Lurch]

Sorry Lurch, I meant to add "Council" to that.

Well as mere mortals aren;t allowed to put cables under council roads it's a moot point.

Cables only need to be as deep as is required, there is no set depth. However, there are plenty of recommendations in guides and books which often get quoted in place of actual regulations.

 

[Megaohm7]

Don't qoute me on this without looking in the BRB but 600mm depth for swa underground does it relate to caravan parks because of the use of tent pegs etc . I have buried swa at least 600mm in the garden myself and marked with warning tape . Just have to consider garden spades , forks and at worst rotovators

 

[Lurch]

522.8.10 says bury to a reasonable depth.

As you say though, for caravan parks 708.521.1.1 suggests .6m minimum on caravan parks due to tent pegs.

705.522 relates to agricultural and recommends .6m generally, and 1m in arable or cultivated land.

740.521.1 is for fairgrounds, and this states reasonable depth again.

709.521.1.7 is for marinas which recommends a minimum of .5m.

So there you go then.

 

[NozSpark]

Seeing as you're in the zone Stuart

How about country fairs (one or 2 day events)?

2" (just under the grass)???

 

[Lurch]

I would say that comes under fairgrounds. 2" could be a reasonable depth, temporary cable, no digging going to be going on etc...