Re: [CAD_CAM_EDM_DRO] Re: Power Supply and Capacitor Questions Help!!

R Rogers wrote:

>Mariss and Jon,
>
> Yes, I entered those values from memory and when I rechecked they were different. Sorry about the confusion. After much preparation and scavenging I got my CNC control assembled enough to test it today. I wired the transformer with the two sets of taps in SERIES and I'm getting about 63 volts DC off the 3 100 volt DC capacitors wired in PARALLEL ( I knew I'd get that right eventually). I wired up one Gecko and followed the Instructions , tuned it the best I could without a scope and after much dithering and oscillation I finally got it smoothened out. Much to my amazement, this is going to work. These DC brush servo motors are very powerful, fast and responsive. I dont have them belted to the axies yet but this bridgeport is going to work very well. The Gecko which I have mounted on a heatsink, even with this large motor, delivered the torque and did not even begin to get warm. Bob Campbells Mach2 breakout performed flawlessly as well. Tomorrow I am going to build Mariss's
> e-stop/dump circuit. One question I do have, Is it possible to accurately tune the Gecko's without a scope? One characteristic my motors are displaying is erratic motion at very slow jog rates. Or is something else causing that? I need to get that resolved and I should be out of the woods then.
>
>

Does the motor settle to exactly the same place after a while? This
would be with
no step pulses from the computer. You could have noise on the encoder
signals.
The symptom would be the motor would eventually settle to a different
position. You may be able to fix this by separating the encoder and motor
wires by an inch or so.

How close are the big filter capacitors to the Gecko drive(s)? If the
wires are
more than 18" or so, Mariss recommends putting a smaller capacitor right at
the DC power inputs to the Geckos.

Jon