A few thoughts - Be sure to allow for battery recharge power + full output load when sizing rectifier input breakers. Use breakers with true RMS current sensing (most modern breakers) to avoid problems with harmonic distortion causing false trips.
You will need to get TCC data for the UPS's internal circuit breakers. Consult with the manufacturer for perimssable settings of internal breakers.
Use care when selecting battery circuit breakers. T-C performance on DC is sometimes different than for the same breaker on AC.
On complex systems, sometimes it's impossible to fully coordinate the various static and maintenance bypass circuit breakers. The primary purpose of some is switching, although they also have overcurrent protection. Carefully consider what you are trying to accomplish with breaker coordination before starting the study. Think through which breakers you would prefer to have trip for overloads and faults.
Make sure you understand how the UPS inverter neutrals are grounded. Commonly grounding is via the bypass source neutral, but sometimes they are separately grounded. This will influence how you set up ground fault protection.
