Re: [CAD_CAM_EDM_DRO] Re: Power supply schematic???

Mike Phillips wrote:

>I use a large Variac rated at 22 amp and some surplus caps that are 10k or 15k uF for each of 3 axis, and a 25smp bridge rectifier. I thought this was a bit crude, but it works very well as it turns out. I wasn't sure my servo motors could handle double their rated voltage, but they still don't get warm driving a series I BP. In fact the accuracy/repeatability went way up with the extra power. I use Mr. Bills Servolite hardware.
>
>

Yes, it is not so well known that PWM amplifiers have gain proportional
to DC
supply voltage. If you turn the voltage up, the gain goes up
proportionately.
The motors won't get any warmer, as the servo amp regulates the power and
supplies only what the motor needs.

One has to be careful with non-isolated power supplies. Some servo
drives are
designed for this, and have several levels of protection to prevent a
shower of
sparks-type disaster. Others do not, and although they may be isolated,
they are not really designed for running directly from the line. A
transformer
isolating the power is just a good idea for safety reasons.

Jon