Gentlemen
After a full on day of conversing with our local sparky, we both ended up totally confused on the issue at hand. After now another 3 hours wasted on google and numerous phone calls around the country, we may have a little light at the end of this subject. From what I have been able to understand from what I have read, the following happens.
Input into the VFD = 240v single phase
output is 240v 3 phase (240v per phase if taken to earth or back to neutral) but still only 240v across phases.
A 415v 3phase motor if the wirings are in star or wye configuration will work fine if wired to delta on the inputs.
Motors that are internally wired delta will need a 415v input across actives or can be run with a Wye - delta starter, these are more likely in very large motors.
I would love for someone to confirm my findings!
Cheers Katoh