I HAVE A BALDOR 3PHASE MOTOR ON A CAROUSEL EXHAUST FAN IN WHICH THE SYSTEM STOPPED WORKING. THERE IS POWER FROM THE BREAKER BOX TO THE FUSE BOX TO THE ADJACENT BOX WHICH I HAVE NO KNOWLEDGE NO [POWER FROM THAT UNKNOWN BOX TO CONDUUIT6 TO MOTOR
If it is a 3 phase motor, it has to have a motor controller/contactor. Usually with overloads. If you have voltage to all 3 poles of the top of the contactor phase to phase, then your input power is ok. Next see if the contactor is closing. If not it will take a bit of tracing out why. I don’t know what you have for control, buttons or switch or interlock with your hood system or a machine.
I don’t have any idea of what you know or what meters and test equipment you have. If you aren’t comfortable with electricity, hire a electrician