PE is used with some equipment to be the terminal for Safety Ground. This means that PE must be connected to your system ground.
Something about the numbers don't add up. For example, the full-load current for a 15kva machine is 21.6 Amps at 400V, not 63 as indicated.
Could the "50/14K 22.8 max amps available" be shorthand for the available short circuit current at the main lugs of the panelboard and the interrupting capacity of the main breaker? Again, the numbers don't sound right for the fault current rating.
