What is the minimum standard size for a main bonding jumper required for a service with two sets of paralleled 750 kcmil conductors?

The minimum standard size for a main bonding jumper in a service with two sets of paralleled 750 kcmil conductors is determined based on the size of the conductors and the requirements established by the National Electrical Code (NEC). The NEC provides guidelines for bonding jumpers to ensure proper grounding and to maintain safety within electrical systems.

For paralleled conductors, the larger conductor size should guide the minimum bonding jumper size. In this case, 750 kcmil conductors have a specific ampacity, and per NEC Table 250.66, the bonding jumper must be at least a certain size relative to the area of the conductors. For conductors 750 kcmil and larger, the NEC dictates a minimum bonding jumper size of 4/0 AWG.

This ensures effective grounding and helps carry any fault currents safely back to the source, significantly reducing the risk of damage or electrical hazards. Therefore, the answer is the minimum standard size for a main bonding jumper required for this service configuration.