Still having the same problem... A couple of professionals have had a look at the machine but so far no progress.

I've studied the ladder diagrams and tried to find something that would cause the power module not to connect the main relay. So far I've discovered that all the axis limit switches do work but none of them are pressed, spindle gearbox switches work, emergency button works, spindle and gearbox lubrication works, hydraulics work...

What I would like to know is that does the power module get some kind of information from spindle or axis amplifiers so that this unleading main relay could be a result of some kind of accessory failure or some other fault? If not, the power module has got to be broken because the only input that it gets via a separate cable is the one from emergency button. And i've measured that it works fine.