NEC Table 250.66 is used for sizing all of the following except?

The answer is based on the specific applications covered by NEC Table 250.66. This table outlines the minimum sizes for grounding electrode conductors based on the size of the largest ungrounded conductor or the service entrance conductors.

The grounding electrode conductors, grounding jumpers, and equipment grounding conductors are all addressed in this table, as they are crucial components of a grounding system that need to be sized appropriately to ensure system safety and performance.

However, the wire-type main bonding jumper is not sized according to this table. Instead, its size is determined by other sections of the National Electrical Code (NEC), especially Section 250.102, which provides guidelines specifically for bonding jumpers. This distinction is essential, as it highlights the unique requirements for main bonding jumpers compared to other grounding components. Understanding this separation helps clarify how different components in electrical systems are regulated in terms of size and applications.