OK, now that makes sense. So as you suggested run the software Estop loop through the 3rd loop on the contactor, then when the latch is released the contactor cuts power and triggers the software e-stop, and build it as per the first schematic i posted ( less the extra stop button ).

second point, are the MCB's i selected of the correct rating for the intended use?

6A C Type for the 24V/6.5A stepper driver PSU (meanwell spec states 2A/230VAC so should the breaker cover the input Amps or the 24v 6.5A? )
16A C type for 1.5KW VFD ( 1500W @ 240V reads more to 8 AMP? )
2A B Type for the Saftey Circuit 24V/2.5A PSU ( again link the stepper PSU should this be sized for the input A and not the output ?)

Thanks again for your help.