SSBJ SIZING FOR PARALLEL PVC RUNS

[Oly]

In sizing the supply side bonding jumper (SSBJ) for parallel runs, table 250.102(c)(1) is now used in the 2014 NEC.

If I have 10, three phase, pvc conduit runs of (x)kcmil copper cable for a total of (10) x (x) kcmil = kcmil,

and if kcmil > 1100kcmil per table 250.1032(c)(1),

then 12.5% of this is (.125) x kcmil] = (z) kcmil,

and if (z)kcmil is > (x)kcmil

QUESTION 1:
CAN THE SSBJ BE REDUCED TO EQUAL AND NOT EXCEED THE PHASE CONDUCTORS?

QUESTION 2:
DOES THE SSBJ AS SIZED HAVE TO BE RUN IN EACH CONDUIT OR
DOES CODE ALLOW (z)kcmil TO BE DIVIDED BY THE NUMBER OF RUNS FOR THE RESULTANT (Z)kcmil / (10) = SSBJ TO BE PULLED IN EACH CONDUIT?

 

[augie47]

As I read it the SSBJ would need to be installed in each raceway and sized to the phase conductors in the individual raceway.
If you were sizing a SSBJ to bond multiple raceways (such as one conductor to several bonding bushings), that jumper would need to be sized based on the sum of the kcmils.

 

[infinity]

As Augie stated you can size the SSBJ in each parallel run based on the size of the ungrounded conductors in each parallel raceway from T250.102(C)(1). Forget about any type of calculation where you divide numbers by the number of raceways.

 

[Oly]

Augie47, thanks for the prompt response.

Bear with me, I need to to expand on this concept for clarity.

For a 10 conduit parallel run installation from transformer secondary (separately derived sytem) to Power Distribution Center (PDC) - If an SSBJ is pulled in each PVC conduit then the size of each SSBJ can be based on the total kcmil of the 3 phase conductors in each raceway?
- Using NEC table 250.102(c)(1), of course.

 

[infinity]

Augie47, thanks for the prompt response.

Bear with me, I need to to expand on this concept for clarity.

For a 10 conduit parallel run installation from transformer secondary (separately derived sytem) to Power Distribution Center (PDC) - If an SSBJ is pulled in each PVC conduit then the size of each SSBJ can be based on the total kcmil of the 3 phase conductors in each raceway?
- Using NEC table 250.102(c)(1), of course.

No, just on one of those conductors.

250.102(C)(2) Size for Parallel Conductor Installations in Two or
More Raceways. Where the ungrounded supply conduc-
tors are paralleled in two or more raceways or cables, and
an individual supply-side bonding jumper is used for bond-
ing these raceways or cables, the size of the supply-side
bonding jumper for each raceway or cable shall be selected
from Table 250.102(C)(1) based on the size of the un-
grounded supply conductors in each raceway or cable. A
single supply-side bonding jumper installed for bonding
two or more raceways or cables shall be sized in accor-
dance with 250.102(C)(1).

 

[Smart $]

Augie47, thanks for the prompt response.

Bear with me, I need to to expand on this concept for clarity.

For a 10 conduit parallel run installation from transformer secondary (separately derived sytem) to Power Distribution Center (PDC) - If an SSBJ is pulled in each PVC conduit then the size of each SSBJ can be based on the total kcmil of the 3 phase conductors in each raceway?
- Using NEC table 250.102(c)(1), of course.

As stated in the left, two-column header:

Size of Largest Ungrounded Conductor or Equivalent Area for Parallel Conductors (AWG/kcmil)

That'd be (x) in your OP...