Underground conduits emerging above ground - support required

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Carultch

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I'm looking to see whether conduit is considered supported, when it is in contact with the soil at grade level.

Given an enclosure that is 3 ft or less from grade, would its conduit stub-up that emerges from the ground require additional support? If so, is there a limit on how high a piece of equipment can be, for its stub to not require support?
 
do you use additional support methods for the portion of the run that is below grade, besides the occasional positioning help before backfilling?

if the earth can't support it you have bigger problems that go beyond the electrical installation, I think.
 
Carultch said:
I'm looking to see whether conduit is considered supported, when it is in contact with the soil at grade level.

Given an enclosure that is 3 ft or less from grade, would its conduit stub-up that emerges from the ground require additional support? If so, is there a limit on how high a piece of equipment can be, for its stub to not require support?
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Look at it the other way. How far from the enclosure (box) can you run conduit before support (strapping ) would be needed (required). Normally 3 ft.
 
Carultch said:
I'm looking to see whether conduit is considered supported, when it is in contact with the soil at grade level.
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Is it in contact with the soil or burried ?

I can lay conduit on concrete and it will be supported but would still need to be strapped.
 
growler said:
Look at it the other way. How far from the enclosure (box) can you run conduit before support (strapping ) would be needed (required). Normally 3 ft.
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I think he is doing that, just questioning if the soil can be that support.
 
growler said:
Is it in contact with the soil or burried ?

I can lay conduit on concrete and it will be supported but would still need to be strapped.
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The majority of the run is buried at the standard 18" burial depth. Obviously you have to transition from buried to non-buried at some point, and that is the part of it which is in question.
 
Carultch said:
The majority of the run is buried at the standard 18" burial depth. Obviously you have to transition from buried to non-buried at some point, and that is the part of it which is in question.
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I would consider emerged from grade as securely fastened if the distance to the run terminus is not greater than the maximum permitted distance (typ.3').

Support of a conduit run is a different animal. In many cases it can continue above grade up to 10ft without additional support.
 
Smart $ said:
I would consider emerged from grade as securely fastened if the distance to the run terminus is not greater than the maximum permitted distance (typ.3').

Support of a conduit run is a different animal. In many cases it can continue above grade up to 10ft without additional support.
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What's the difference between support and secure? Intuitively, I would expect that "support" would mean primarily constrained against gravity, whereas "secure" would mean constrained in all axes and possibly constrained against bending as well.
 
Carultch said:
What's the difference between support and secure? Intuitively, I would expect that "support" would mean primarily constrained against gravity, whereas "secure" would mean constrained in all axes and possibly constrained against bending as well.
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Just the basics... pretty much as you have stated. There is no NEC definition.
 
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