Router has died. Need Advise Please.

[Bush Flyer]

It doesn't say what the slow speed is on that spindle, but as you can see I cut mostly balsa and ply but I still have this 6mm aluminium to cut and There may be another job if this one works out.
What do you think about the min watts I could run. Also is the VFD easy to set up I see the reading are in Hz and I do not understand what Hz are in relationship to RPM?

[EddyCurrent]

Also is the VFD easy to set up I see the reading are in Hz and I do not understand what Hz are in relationship to RPM?

rpm = (frequency (Hz) x 60 (seconds)) / number of pairs of poles.

so for example: a 4 pole motor connected to 50 Hz mains supply. rpm = (50 x 60) / 2 = 1500
This is the theoretical speed, the actual speed is rather less because the motor need 'slip' so it works out about 1425 rpm at the rated load.
My spindle is rated at 24000 rpm at 400 Hz so it must be a 2 pole motor

number of pairs of poles = (400 x 60) /24000 = 1, therefore number of poles = 2

edit: Geoffrey, looks like we both posted at the same time