Re: [CAD_CAM_EDM_DRO] Servo motor HP for Bridgeport

info.host@... wrote:

> > (I also need to know DC power supply voltage
> > and peak current capability of the servo amps.)
>
> Why is it Gecko recommend a voltage supply 4 to 25 times that which the
> motor is rated for?

All stepper systems need a power supply that is higher than the motor's
rated voltage to overcome the inductance (think of it like inertia of the
current) in the windings. If you had just the rated voltage, it would take
eternity for the current to rise to the full rated amount. Old stepper
drivers
used series resistors that allowed the current to come up to the desired
amount, and then the voltage drop on the resistor was just enough to
keep the current from rising any more. This wasted a lot of power, though.
Newer, 'chopper-type' drivers use switching transistors to cut off the
voltage when the current reaches the desired level, then switches it
back on if the current drops a bit. In between, diodes allow the current
to recirculate in the winding. To get good torque at higher speeds, the
driver needs a higher voltage to allow the current to rise quickly.
Little power is wasted anywhere but in the winding resistance of the
motor.

Jon