Thanks for taking the time to wire up a stepper & drive to a lab power supply Jonathan. I thought that the Power In = Power Out (V*I[in] = V*I[out]) only applied to transformers and voltage doubler circuits, given the stepper is acting as a chopper circuit, and no voltage change is taking place [albeit the stepper coil is an inductor].

separate AM882 question ->

seems you can get 3 variants of the AM882 drive, the AM882 (which has a datasheet from Leadshine), an AM882H, which seems to be above to take AC + DC and at a slightly higher voltage, and a AM882-DK (which is apparently a dedicated drive for an engraving machine).

The AM882H seems to have a fan as well, anyone got any experience of these (as I can't find an English language PDF) are they the same as the AM882, but with a heatsink mounted fan, and has a listed supply voltage of 18-70 VAC & 24-100VDC, with the supply terminals listed as "AC"

seems the AM882H can be had for ~£48

Any comments / experience would be very much appreciated.

Thanks again for your time,