Pull Box

[timm333]

We have NEC rules 314.16 and 314.28 for pull box calculations of power cables. Which rule will apply for the pull box calculations of communication cables?

Also for pull box calculations of power cables, we use the sizes of individual conductors (12 AWG, 4/0 AWG, etc) instead of the outer diameter of the cable. But for communication cable: I don't have the sizes of the individual conductors, and I only have the outer diameter of the cable; how shall we size the pull box in this case? Thanks

 

[jumper]

We have NEC rules 314.16 and 314.28 for pull box calculations of power cables. Which rule will apply for the pull box calculations of communication cables?

Also for pull box calculations of power cables, we use the sizes of individual conductors (12 AWG, 4/0 AWG, etc) instead of the outer diameter of the cable. But for communication cable: I don't have the sizes of the individual conductors, and I only have the outer diameter of the cable; how shall we size the pull box in this case? Thanks

That is not the correct way to size a multiconductor cable. See Chapter 9, Table 1, Notes 5 and 9.

 

[timm333]

Table 1 is for conduits. So should I take the outer diameter of the communication cable to size the conduit, and then use rule 314.28 to calculate the pull box size for the communication cable?

 

[timm333]

Rule 314.28 applies to #4 AWG and larger: is this (#4 AWG) the size of individual conductors of multi-conductor cable, or is this the size of the outer diameter of the cable?

 

[kwired]

Might want to keep in mind some communications cables may have recommended minimum bending radius that must be followed or performance could be compromised.

 

[timm333]

The cross sectional area of #4 AWG cable is 0.032 square inches. So should we do the following?

1) Calculate cross sectional area of the outer jacket of the communication cable.
2) If this area is 0.032 square inches or less, then uses rule 314.16 for pull box sizing.
3) If this area is greater than 0.032 square inches, then use NEC rule 314.28 for pull box sizing.

 

[kwired]

The cross sectional area of #4 AWG cable is 0.032 square inches. So should we do the following?

1) Calculate cross sectional area of the outer jacket of the communication cable.
2) If this area is 0.032 square inches or less, then uses rule 314.16 for pull box sizing.
3) If this area is greater than 0.032 square inches, then use NEC rule 314.28 for pull box sizing.

I'd say find out if there is minimum bending radius specifications for said cable, or at least minimum specifications for performance.
My understanding for cat 5 cat 6 cables is too sharp of a bend may not damage the cable but may effect possible speed of data transmission.