Underground conduits

[Dustin Foelber]

Good morning gentlemen
I have a project that requires us to route a 2" PVC trunk line to multiple camera locations. This conduit will house RG59 for video feed and 18/2 for 12 volt DC. We are saw cutting asphalt vehicle pathway through private party condo complex to remove and trench. Is this conduit governed by the 24" min depth req. for parking areas. Any way I can avoid this. TO go 24" would be extremely difficult in this area. I am a high voltage electrician and my LV tech does not no NEC. Any help on this one would be much appreciated
Thanks
H.I.C. Electric

 

[jumper]

I do not think 300.5 applies to your application. 24" is not needed IMO.

 

[augie47]

I have seen the installations at less than 24" often, and jumper may be correct, but I can not find anything in the NEC that supports it not being 24". It sounds like a Class 1 Circuit and 725.46 states that Class 1 circuits shall be installed according to Part 1 or Art 300 which includes 300.5.

I may be overlooking something and I would definitely check with your AHJ as I see installs less than 24" often.

 

[jumper]

I have seen the installations at less than 24" often, and jumper may be correct, but I can not find anything in the NEC that supports it not being 24". It sounds like a Class 1 Circuit and 725.46 states that Class 1 circuits shall be installed according to Part 1 or Art 300 which includes 300.5.

I may be overlooking something and I would definitely check with your AHJ as I see installs less than 24" often.

If this is a Class 1 circuit, I am in error. I thought this was a Class 2 circuit.

 

[augie47]

Jumper, you very well may be correct on the Class of circuit. My expertise in Art 725 leaves a lot to be desired.
That said, can you direct me to a Code section that exempts Class 2 wiring from 300.5 ? I fail to find it.

 

[jumper]

Jumper, you very well may be correct on the Class of circuit. My expertise in Art 725 leaves a lot to be desired.
That said, can you direct me to a Code section that exempts Class 2 wiring from 300.5 ? I fail to find it.

Simple, since 300.5 is not referenced for Class 2 circuits, you do not have to follow it. You cannot find it because it is not there. Chris(Raider1) taught me this.

 

[jumper]

This was the thread

http://forums.mikeholt.com/showthread.php?t=125143&highlight=300.5

 

[augie47]

Playing devils advocate here, 725.130 refers us back to 725.46 which requires Art 300 compliance.
Although often overlooked, I can find no exception that allows less than 24".
Barring additional input, we may just have to disagree,

 

[raider1]

Simple, since 300.5 is not referenced for Class 2 circuits, you do not have to follow it. You cannot find it because it is not there. Chris(Raider1) taught me this.

Correct, for Class2 and Class3 circuits Article 725 does not reference 300.5 for burial depth for these circuits.

Most likely a 12 volt DC circuit won't be a class 1 circuit.

Chris

 

[augie47]

Roger, How about 725.130(A) referencing 725.46 referencing Art 300.

 

[raider1]

Playing devils advocate here, 725.130 refers us back to 725.46 which requires Art 300 compliance.
Although often overlooked, I can find no exception that allows less than 24".
Barring additional input, we may just have to disagree,

Yes, 725.130(A) referers back to 725.46 when you are using a chapter 3 wiring method for a class 2 or class 3 circuit, but if you are using a class 2 or 3 wiring method then 725.130(B) does not refer you back to 725.46.

When using a class 2 or 3 wiring method I don't see anything in Article 725 that requires you to comply with the burial depth specified in 300.5.

Now in the original post, they mentioned 18/2 I assumed that was a class 2 or 3 cable.

Chris

 

[augie47]

That clears it up. Sometimes I need help reading
I bow to and apprecaite your knowledge and input.
(thats why you make the moderator big bucks)

 

[raider1]

That clears it up. Sometimes I need help reading
I bow to and apprecaite your knowledge and input.
(thats why you make the moderator big bucks)

I will be glad to share the chief moderator salary with you

Chris

 

[charlie b]

I don't know anything about "class." But let me ask this: Can we not use the 6 inch depth from the top right hand cell in table 300.5? I know it says "irrigation and landscape lighting." But it also says less than 30 volts, and the application is not all that different. So long as the cable (or raceway) is identified for direct burial, should not this be applicable to the present situation? Why, for example, is an irrigation system allowed to be buried at 6 inches, but not a camera system?

 

[jumper]

I don't know anything about "class." But let me ask this: Can we not use the 6 inch depth from the top right hand cell in table 300.5? I know it says "irrigation and landscape lighting." But it also says less than 30 volts, and the application is not all that different. So long as the cable (or raceway) is identified for direct burial, should not this be applicable to the present situation? Why, for example, is an irrigation system allowed to be buried at 6 inches, but not a camera system?

You can use 300.5 if you want to, but you do not have to.The camera system can be buried at 6 inches.

 

[raider1]

I don't know anything about "class." But let me ask this: Can we not use the 6 inch depth from the top right hand cell in table 300.5? I know it says "irrigation and landscape lighting." But it also says less than 30 volts, and the application is not all that different. So long as the cable (or raceway) is identified for direct burial, should not this be applicable to the present situation? Why, for example, is an irrigation system allowed to be buried at 6 inches, but not a camera system?

725.3 states that only those sections of Article 300 referenced in Article 725 shall apply to class 1, 2 or 3 circuits.

725.130(A) specifically references 725.46 which requires that you follow Part I of Article 300. This applies to using a Chapter 3 wiring method for class 2 or 3 circuits. So if I choose to use UF cable for low voltage lighting then I must comply with the burial depths of column 5 of Table 300.5.

If I use a Class 2 or 3 direct burial cable then 725.130(B) does not reference following Part I of Article 300 so I would be permitted to use Column 5 but not required.

Chris