Been away for the past week (my Golden wedding aniversary celebrations?), so sorry to be harping back to one of the non technical points. If your motor is marked as 230v 3 ph you can almost certainly run that coolant pump on single phase. Set the motor block connecters to Delta and either use a vfd or trick the motor to run in quasi 3 phase using a couple of caps. I have been running 3ph motors on 230v single phase for over 20 years and have never had any problems. It may be neccessary to use a separate switched cap for starting. If in any boubt, cap values etc. you can PM me. Your project is looking great. Well done. G.