Article 530 - 530.23 Overcurrent Protection

[psaffa]

530.23 (A) 'Portable Stage Cables' requires protection to comply with the cable ampacity per Table 400.5A(2)
530.23 (B) states that cables be protected by an overcurrent device set to not more than 400% of the cable ampacity in Table 400.5(A)(2).

This is confusing that the OC protector can be set to 4X what the max cable ampacity rating is.
Can someone explain?

Thanks,
Paul

 

[tortuga]

530.23 (A) 'Portable Stage Cables' requires protection to comply with the cable ampacity per Table 400.5A(2)
530.23 (B) states that cables be protected by an overcurrent device set to not more than 400% of the cable ampacity in Table 400.5(A)(2).

This is confusing that the OC protector can be set to 4X what the max cable ampacity rating is.
Can someone explain?

Thanks,
Paul

In the 2023 NEC
530.23(A) applies to portable stage cables and pulls in 240.5, in essence 'branch circuits'.
530.23(B) only applies to feeder cables.
My take is the 400% is like feeder tap rules. You can tap a 50A feeder cable off a 200A cable.
Keep 530.4 in mind, there should be a best boy on site.

 

[psaffa]

Thanks. While searching for something relevant on line, I found a reference to this topic in an except from the Wisconsin electrical standard.
It stated that due to filming short scenes, normally 10 minutes or less, the overcurrent protection for lighting can
be rated at 400%.