NEC Section

The NEC does not explicitly state that you cannot feed two separate 200A panels from a single 200A circuit breaker. However, the inspector's requirement is likely based on the following sections: NEC 210.4(A): Requires feeder conductors to have ampacity sufficient for the maximum load calculated or measured on the panel they supply. NEC 225.31(A)(3): Overcurrent protection for feeders of multiple occupancy buildings (such as multi-family dwellings) shall be provided for each set of panelboards or other distribution equipment that is separately metered.

Inspector's Concerns

The inspector's concerns may be related to: Parallel Conductors

Running parallel conductors from a single circuit breaker to two separate panels can increase the overall impedance and reduce the effective current-carrying capacity of the conductors.

Load Balancing

If the loads on the two panels are unevenly distributed, one panel could be overloaded while the other is underloaded. This could lead to overcurrent protection not adequately protecting the overloaded panel.

Metering (if applicable)

In multi-family dwellings, it is important to provide separate overcurrent protection for each tenant's unit to ensure accurate metering and billing.

Possible Solutions

To address the inspector's concerns, you could consider: Using a Distribution Panel

Install a 200A main distribution panel and feed the two 200A panels from there. This would provide overcurrent protection for each panel and allow for better load balancing.*

Installing Separate Circuit Breakers

Install a separate 200A circuit breaker for each panel in the junction box. This would provide dedicated overcurrent protection for each panel.

Conclusion

While the NEC does not explicitly prohibit feeding two separate 200A panels from a single 200A circuit breaker, it is important to consider the inspector's concerns and find a solution that meets the intended use and safety requirements of the installation. Flag for review