The circuit breaker with a total power of about 90 kW should be able to work normally. If a leakage circuit breaker is used, it may trip due to leakage. But according to your introduction, the main brake is not hot. Push it again after tripping for more than ten minutes, and it can return to normal ",which should be caused by the overload of the circuit breaker.

The possible cause of the trip should be that a large number of single-phase loads in the hotel are unevenly distributed in the three-phase power supply, which leads to the overload of a certain phase and leads to the trip.

Solution: When the load is maximum, measure the three-phase currents respectively, and adjust part of the load of one phase with excessive current to the other two phases, so that the three-phase currents of the line are basically balanced.