Screw Compressor 250kW 3ph 630A MPCB Fails After Power Interruptions—Why?

Hello , i'am facing a screw compressor breaker issue , lately a lot of power interuption hapens and the breaker trips when it hapens , but now the breaker don't even work, i mesured the same phase in two points of the breaker output, its   3 ph + N  630A MPCB but we only use the 3 phases output, its runing a 250 Kw compressor AC motor  in Delta/star,  here is the MPCB parameters set in the attachments, i checked the compressor circuit and motor and it doesn't look like there is a problem in it, so are those interuptions the reason for those MPCBs keep failing , and if yes can you explain why ? thank you 

Hi Seddik-Is the motor operated directly from the breaker, or is there a soft start or VFD that may have failed?Also, I wonder if there is an unloader that may be stuck. An unloader is often just a solenoid valve or a mechanism that holds the compressor valves open until the motor comes up to speed.For those who may not be familiar with the acronym, an MPCB is a "Motor Protection Circuit breaker" that often has both thermal and magnetic trips.  They allow a high inrush so the motor can come up to speed without tripping the breaker.-Rick