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Juan for the road
08-12-2008, 08:19 AM
What does the code specify as the minimum depth of burial for UF cable.The cable is 12/2 UF(direct burial).Burial in the trench will be unprotected.It will be protected with a 20a GFCI breaker.

How many cables am I permitted to bury off of this circuit?

What does the code call for, for protection ,as it makes it's way into and out of the ground?

Billy_Bob
08-12-2008, 09:00 AM
Basically everyone goes by the NEC. But certain areas have their own modifications to the NEC for this and that.

One of these modifications could be differences in burial of electrical cables depending on the local ground conditions. For example some areas have permafrost. Others have a very high water table. Others lots of sharp rocks in the ground. Some areas have plenty of nice [non-wire damaging] sandy soil.

So I would ask your local electrical inspector.

Billy_Bob
08-12-2008, 09:05 AM
P.S. Code or no code, I like wires coming out of the ground next to a house (outside wall) to be in conduit. This is for lawnmower/weedeater damage which can occur.

Chris75
08-12-2008, 01:16 PM
The answer is 12"

5158

Billy_Bob
08-12-2008, 04:24 PM
I'll tell ya... When I'm burying electrical cable, I like it to be deep (like at least 18 inches). I consider what else might be dug in that area in the future... Tree holes, sprinkler system, garden tilling, or even a dog digging! Then I am sure to go deeper than that.

Some people recommend fence posts be installed 2 ft. deep for example (due to wind).

But I live in an area where the ground is soft and easy to dig deep. I appreciate that in some areas like southern Arizona, the ground is so hard you almost need a jack hammer to break it up! (Actually I have heard of them doing that there.)

If it is something like a sewer line, water line, etc. being installed in the future, they should have enough sense to find out where lines are already buried.

It is a pain to dig a hole for something and cut an electrical line. I once saw where a guy was just smoothing out a road with a tractor and he cut a main telephone line. That line was not burried more than a few inches deep!

Juan for the road
08-15-2008, 06:30 AM
P.S. Code or no code, I like wires coming out of the ground next to a house (outside wall) to be in conduit. This is for lawnmower/weedeater damage which can occur.

This is referenced in the NEC,I believe.Code experts?

jwelectric
08-15-2008, 06:53 AM
This is referenced in the NEC,I believe.Code experts?
(D) Protection from Damage. Direct-buried conductors and cables shall be protected from damage in accordance with 300.5(D)(1) through (D)(4).
(1) Emerging from Grade. Direct-buried conductors and cables emerging from grade and specified in columns 1 and 4 of Table 300.5 shall be protected by enclosures or raceways extending from the minimum cover distance below grade required by 300.5(A) to a point at least 2.5 m (8 ft) above finished grade. In no case shall the protection be required to exceed 450 mm (18 in.) below finished grade.
(2) Conductors Entering Buildings. Conductors entering a building shall be protected to the point of entrance.