Re: Servo motor voltage

Darcy,

Bad advice. That diode will certainly wreck most drives; where is the
returned energy to go then?

A 20mH motor carrying 20A has 4 joules of stored L*I^2/2 energy. 4
joules of energy delivered to a 55,000uF capacitor would raise its
voltage by only 12V.

Because there is no compelling reason to return the servo "brake"
energy, we use a non-regenerative switching topology. The mechanical
energy is dissipated in the motor rather than being returned. Only
the inductive component must be dealt with.

Mariss

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Parker, Darcy "
<dparker@p...> wrote:

> Some other advice, make sure there is sufficient capactiance and a

diode to prevent regenerative current from the motor during braking
from wrecking the power supply.

>
> Darcy