Some question about understanding the electrical data of a manual
1-) At page 35 under Electrical Data, the manual says I need to use a 24V power supply which is PELV type. Is this 24V supply needed for break? And what can be the reason that PELV is required?


The 24V supply seems to be required for the "Safe Torque Off" (STO) feature. I found some description of that in the manual P53, but you may want to search for more information from Kollmorgan or in the referenced standard.


  2-) Again at page 35 under Electrical Data, What is meant by:


-current B, P, T types without/with motor brake ?

The different model variations are described in the manual. The note indicates the data is for the model variations mentioned.


  3-) At page 42 for the regenerative resistor, the following is recommended:
  
  Does that mean a 33 Ohm 1.5kW resistor is adequate? Can it be any type of resistor like wire wound or Aluminium Enclosure Resistor? How important is to install this resistor?


Some types of resistors may need to be selected according to the 1 second peak power. You would need to look at the resistor manufacturer's data. I believe that bare wire resistors have less difficulty with pulsed power than those having the wire embedded in ceramic material. I believe the capacitor energy indicates how much braking energy can be absorbed without needing resistors. The need for resistors is dictated by the desired deceleration rate, the friction, the inertia and the efficiency of the motor and drive during braking.


  4-) Is the "drive cut-out" in the figure I added at the beginning a contactor switch or a circuit breaker?


That looks like a contactor to me. You might learn more by searching to find out what the STO feature is all about.