Junction Box size

[nkalghatgi]

I want to size a junction box for tree uplights. There is one 1" conduit entering and leaving the junction box which goes to the next junction box. From each junction box the connection is made to the receptacle which probably might be attached to the junction box itself. How do I size this junction box ? I am not sure what the wire size would be. Let us assume its 4 AWG.

 

[augie47]

With #4 and larger you use 314.28 which is based on your conduit size.
For #6 and smaller you use 314.16 which is based on cubic inch.

(With #4s and (2) 1" conduits the smallest "standard size" box would probably be a 8+ x 8..wall opposite the conduit entries would have to be 7")

 

[nkalghatgi]

Thank you for answering my question. I really appreciate it. That means the smallest size I can use is 8"(length)x6"(height) and depth has to be 7".

 

[augie47]

Thank you for answering my question. I really appreciate it. That means the smallest size I can use is 8"(length)x6"(height) and depth has to be 7".

Not necessarily...
There are variables. please see the Article... it depends on where the conduits enter, where the cover is, etc.
Basic rule... angle pull or splice.. 6X the conduit entry + other conduits in the same row and 6X between entries, but if your conduits enter the back (opposite the cover) there is a reduced dimension.
If you use #4 conductors, bring the conduits in from the bottom (opposite the removable cover) your box would only have to be 2" deep.

The devil is in the details.. you need to read that section,...

 

[nkalghatgi]

In my case, I have one 1" conduit entering the junction box and one 1" conduit leaving the junction box. I might have a receptacle tied to the junction box so the connection have to be made to the receptacle. This is going be an underground junction box probably with no bottom. In this case the minimum width has to be 8" (Am I correct). I want to know what would be my depth in this case?

 

[augie47]

Way too many variables ..I can only surmise What I am picturing is a Quazite type enclosure... open bottom, removable cover...

314.29 & 314.30 would require the cover be accessible (see exception)..
(2) 1" conduits would have to be spaced with 6" between them..
the depth would depend more on the layout..(conduits turned up into the box or straight in, etc) but it could be as little as 4" deep (see 314.30(A))

 

[nkalghatgi]

Thank you. I really appreciate your response.