With time on my hands, I decided to try a technique that I noticed first in a L200 voltage regulator data sheet. It is fig 25 in STM’s ‘A Designer’s guide to the L200 voltage regulator’ (ST webpage ...
At last, motor controller set up, milling machine re-assembled and working. Phew. All was not quite perfect, but pretty good. The installation (right) Plenty of insulation on the back of the controls ...