Inrush current and number of devices per MCB
The driver data given and the circuit breaker curves should be sufficient to determine how many can be connected. You should me able to add the currents together. If there is more than one kind of driver with different inrush durations, the addition would be a little more complex. All of the drivers connected simultaneously would probably represent the worst case, but you might need to evaluate the effect of individual or groups of drivers connected in rapid sequence.