Quote Originally Posted by Mariss Freimanis View Post
Returned energy: Never post until the brain is fully saturated with caffeine; it wasn't and I wasn't thinking. The theoretical maximum returned voltage is twice the supply voltage, i.e. motor back EMF equal to supply voltage, '-' side of motor to 'on' top bridge MOSFET.
I think it's not that way. Drive acts as step-up converter during braking where motor acts as inductor. So voltage can be pumped up almost infinitely. During braking current direcition just reverses and motor EMF doesn't play any role.

Attach more mass to the 48VDC motor and try running the test again