Which NEC table is used to size a wire type main bonding jumper?

The selection of Table 250.102(C)(1) from the National Electrical Code (NEC) is correct because this table specifically addresses the sizing of the main bonding jumper based on the size of the service entrance conductors. The main bonding jumper is crucial for ensuring a low-resistance path for ground fault currents, which in turn enhances safety by reducing the risk of electrical shocks and equipment damage.

Table 250.102(C)(1) indicates the appropriate size for the main bonding jumper corresponding to the size of the conductors supplying the service or the size of the feeder conductors, depending on the installation. This table takes into account various conductor materials and ensures that the sizing adheres to safety and performance requirements.

In contrast, Table 250.24 deals with grounding conductors and their adequacies in relation to service equipment, while Table 310.16 provides ampacity ratings for conductors, which is not relevant for bonding jumper sizing. Table 250.66 pertains to grounding electrode conductor sizing, focusing on connections to grounding electrodes and their requirements, and is separate from the bonding jumper considerations. Thus, the specificity of Table 250.102(C)(1) directly relates to sizing main bonding jumpers, making it the appropriate reference