Table 300.5

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A/A Fuel GTX

A/A Fuel GTX

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Can I assume that a PVC raceway under a commercial driveway is legal if encased in 2" of concrete regardless of burial depth? Assumption based on Note 2.
 
That is not what the note is telling us. Note 2 has nothing to do with burial depth; you need to use the tabulated values for that information. What Note 2 is saying is that if you have a conduit that is allowed to be buried within concrete, but that is not allowed to be buried without the concrete, then when you build the concrete encasement you need to have at least 2" of concrete all aroung the conduit. How much dirt you need above the top of the concrete is not addressed by that note.
 
jumper said:
I know the table, I have always been speced at that depth, I am just not sure that if you use that 2" concrete idea if 12" is okay.
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it seems to me the way it is worded that the 2" concrete refers to the amount of encasement required if encasement is required, but has nothing at all to do with burial depth.
 
jumper said:
What conduit would require encasement in concrete if it is buried? Not talking about over 600V or inside a building.
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That is what it says.

2. Raceways approved for burial only where concrete encased shall require concrete envelope not less than 50 mm (2 in.) thick.
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I never heard of any raceway that is only approved for burial. is there such a thing? maybe the polypropolene stuff?

I think it is trying to say that if the raceway is only approved for burial, and you decide for whatever reason to encase it in concrete, that the concrete has to be at least 2" thick.
 
jumper said:
What conduit would require encasement in concrete if it is buried? Not talking about over 600V or inside a building.
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from 2012 UL White Book:

RIGID NONMETALLIC CELLULAR CORE SCHEDULE 40 AND SCHEDULE 80 PVC CONDUIT (DZLR) ....
Unless marked for higher temperatures, rigid nonmetallic cellular core PVC conduit is intended for use with conductors and cable rated 75?C or less, including where it is encased in concrete within buildings and where ambient temperature is 50?C or less. Where encased in concrete in trenches outside of buildings, it is suitable for use with conductors and cable rated 90?C or less. ....

RIGID NONMETALLIC PVC CONDUIT (DZYR) ....
Type A, Type EB and Schedule 40 conduit is intended for underground
use under the following conditions, as indicated in the Listing Mark:
Type A ? Installed with its entire length in concrete in any underground location.
Type EB ? Installed with its entire length in concrete in trenches outside of buildings.
Schedule 40 ? Direct burial with or without being encased in concrete. ....

Unless marked for higher temperature, rigid nonmetallic PVC conduit is intended for use with wire rated 75?C or less including where it is encased in concrete within buildings and where ambient temperature is 50?C or less. Where encased in concrete in trenches outside of buildings it is suitable for use with wires rated 90?C or less. ....

RIGID NONMETALLIC HIGH-DENSITY POLYETHYLENE UNDERGROUND CONDUIT (EAZX) ....
Unless marked otherwise, HDPE conduit is intended for use with wire rated 75?C or less, or when directly buried or encased in concrete in trenches outside of buildings, it may be used with wire rated 90?C or less. ....
 
fmtjfw said:
from 2012 UL White Book:

RIGID NONMETALLIC CELLULAR CORE SCHEDULE 40 AND SCHEDULE 80 PVC CONDUIT (DZLR) ....
Unless marked for higher temperatures, rigid nonmetallic cellular core PVC conduit is intended for use with conductors and cable rated 75?C or less, including where it is encased in concrete within buildings and where ambient temperature is 50?C or less. Where encased in concrete in trenches outside of buildings, it is suitable for use with conductors and cable rated 90?C or less. ....

RIGID NONMETALLIC PVC CONDUIT (DZYR) ....
Type A, Type EB and Schedule 40 conduit is intended for underground
use under the following conditions, as indicated in the Listing Mark:
Type A ? Installed with its entire length in concrete in any underground location.
Type EB ? Installed with its entire length in concrete in trenches outside of buildings.
Schedule 40 ? Direct burial with or without being encased in concrete. ....

Unless marked for higher temperature, rigid nonmetallic PVC conduit is intended for use with wire rated 75?C or less including where it is encased in concrete within buildings and where ambient temperature is 50?C or less. Where encased in concrete in trenches outside of buildings it is suitable for use with wires rated 90?C or less. ....

RIGID NONMETALLIC HIGH-DENSITY POLYETHYLENE UNDERGROUND CONDUIT (EAZX) ....
Unless marked otherwise, HDPE conduit is intended for use with wire rated 75?C or less, or when directly buried or encased in concrete in trenches outside of buildings, it may be used with wire rated 90?C or less. ....
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Cool. Good info.
 
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