Newbie- Mitsubishi MR-J2S-xxA wiring issue

[LCY]

first of all i must apologize for my bad english, here is my story goes

few weeks ago i bought some used drive and motor from ebay, been reading the manual for few days before power them up until yesterday, finally i had finish the wiring and sucessfully power the drive on withouth any issue but i can hear some weird noise come from the driver, some high pitch sound come from the driver. is that normal? or its just the noise filter (not suitable) dont work? or i did wired something in the wrong way already?

and i really want to know what is the purpose of "magnetic contactor", is it a must for the drive? also the "no fuse breaker", as i can power them up without them.

also the "surge absorber" is mentioned in the manual said "a surge absorber is required for the electronic brake" but i dont know where they should be attach at.

what is "line noise filter", what is "emc filter", what is "radio noise filter"? they are mentioned in the manual, i wonder if i really need them?

any help are appreciated