250.28(A) Main Bonding Jumper and System Bonding Jumper Material.

NEC 250.28(A) permits aluminum and copper-clad aluminum main bonding jumpers which aligns with Table 250.102(C)(1).
Click to Enlarge
NEC 250.28(A) permits aluminum and copper-clad aluminum main bonding jumpers which aligns with Table 250.102(C)(1).

Main bonding jumpers are permitted to be made of aluminum and copper-clad aluminum. Table 250.102(C)(1) specifies the minimum size main bonding jumper permitted based on the conductor material type.

Section 250.28(A) provides a list of items and conductors suitable to be used as a main bonding jumper which aligns with materials shown in Table 250.102(C)(1).

Below is a preview of the NEC®. See the actual NEC® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the 2020 NEC® edition of NFPA 70.

2020 Code Language:

250.28(A) Material. Main bonding jumpers and system bonding jumpers shall be of copper, aluminum, copper-clad aluminum, or other corrosion-resistant material. A main bonding jumper and a system bonding jumper shall be a wire, bus, screw, or similar suitable conductor.

Did You Like This? Let Us Know With A Like! Thanks!

250.28(A) Main Bonding Jumper and System Bonding Jumper Material.

Below is a Real Question from our Electrical Continuing Education Courses for Electrical License Renewal:

Refer to the image of NEC Table 250.102(C)(1):

What is the minimum size aluminum main bonding jumper permitted if the ungrounded conductors are 500 kcmil aluminum?

A: 1/0 AWG aluminum.
B: 2/0 AWG aluminum.
C: 3/0 AWG aluminum.
D: 4/0 AWG aluminum.
Please register or sign in for electrical continuing education courses.

If you were already signed in, your session probably expired, please sign back in.