Shiz - broken down!!!

Well actually it's me that's been breaking the Shiz down - it didn't fail on me.

Now that I have the Acorn controller and PC set up, I've decided the time has come to stop buggering about and get on with building up the new control system. First - remove the old console, Chinese controller and all the drives. Then start to reassemble the carry over parts onto the new baseplate.

I know, I know, the wiring was a complete mess but I'd have been gutted if I'd done a really professional job and then had to scrap it like this. Besides, there wasn't enough room to get decent access (my fault) and wire it all up properly and the Chinese wiring tails were too fine (tiny wire gauge) to terminate sensibly. So it's a good thing I made such a pig's ear of it ;-)

Breaking it up:

These pics are to show (me) how it was connected up.

The first of the top switches on the Z axis (quill position) is used as an interlock to prevent the power drawbar operating with the spindle lowered (yellow wires). It also requires the VFD to report "spindle stopped". When both conditions are true, the SSR in the drawbar controller is powered (12V), then the power drawbar can do its little thing.

This spider's nest shows the various limit switch connections. The X, Y & Z +L hard limit switches are all in series, same with the -L hard limit switches. The 3 axes each have their own home switches. Will have to share one common input on the Acorn I suspect.

I managed to remove the inner tray without screwing up my back again:

Just the chassis remains:

And even that has now gone:

That massive steel infrastructure will be able to come off finally:

Here's the tray without the rear heatsink / drivers etc:

VFD connections:
For the record, here are the connections for the VFD, including the braking resistor and motor phase connections:

100VAC transformer:

When originally setting up the new drives (for the Chinese controller), rather than fork out loads of dosh for a large SMPS, I simply went for the low tech solution. My CNCdrives.com "DG4S-16035" DC brushed servo drives require a maximum of 160VDC - less some headroom of course. And I have a "BRKC-180" braking module to cope with any regen voltage due to rapid deceleration. Bottom line is I need about 140VDC or so on the unloaded DC bus. 

So I dismantled a brand new 3kVA site transformer and removed enough of the secondary winding to reduce the output as required. Worked out nicely but I didn't get around to rewelding the laminations back together in case I had to go back in and finesse the turns any further.

The transformer is a bit noisy now, due to the air gap and large AC field therein. So this is a good time to weld the lams back together. Out with the MIG:

Not pretty, due to some of the varnish getting into the arc but it's more than adequate and the reduction is noise (50Hz hum) is significant. So that's a major improvement. Also have no need for the steel wall-mounting enclosure for the transformer, so that can get the old heave-ho too.