The am882h drives have built in bridge rectifiers and caps, but when I had the cover off (I was curious they were sold as refurbished) I should have written down the capacitance of the caps, hence the ripple can then be calculated.

My switch mode is 720w at 42v and it can make a bit of noise when all three axis are running at the same time. Even though in theory it's rated at 14amps.

Not so sure about 500va given its 250va per tapping (5amp) and the drives run at 4.2a hence if two axis are running off the same tapping at the same time they would draw worst case 8.2a, hence why I was edging toward 1000va (500 va per tapping or 10a rating at 50v)

Thanks for the comments (any comments)

Brad