2023 NEC Table 250.102(C)(1)

[rojay]

I was hoping to get some clarification-

Does anyone know why the note regarding multiple sets of service entrance conductors or transformer secondary conductors (formerly Note 3 of 2020 NEC) was removed from the 2023?

For example, what if I wanted to use a single supply side bonding jumper to bond two service raceways in a meter before they run to their separate service disconnect enclosures?

The current language seems to be stating that combining the areas of ungrounded service conductor sets in each raceway to size a single SSBJ only applies to parallel conductor installations.

Am I missing something or overthinking this by making the assumption that connected in parallel means the “310.10(G) electrically joined at both ends” sense?

 

[don_resqcapt19]

The substantiation for that change said:

By including the requirement for using the circular mil area of single or sets of conductors in parallel, in Notes 1 and 2, the existing note 3 is no longer needed. In addition, it is necessary to add text to the existing Note 4 related to the rating of an overcurrent device. It is common to install service conductors that are larger than the load to comply with 230.90(A) for the rating of an overcurrent device.

However I believe you are correct the the service conductors may not always be connected in parallel, that is they may terminate on multiple service OCPDs. They made a mistake when this change was accepted, even though the submitter is a former chair of CMP5.

I would just apply the parallel rule, unless the AHJ says you can't.

 

[rojay]

Thanks for the info! One little missing note on a table used to size four different conductors can really muddy the water