Re: [CAD_CAM_EDM_DRO] Servo Drive Question..Help!

cnc6805 wrote:

>
> I am currently setting up a bridgeport for CNC operation and I
> intend on controlling it with Mach1 on a PC. The servo motors I have
> are Allen Bradley 40.5 in/lb motors they are rated at 2500 RPM and 13
> Amps continuous and 30 Amps peak.

> If someone would, just breifly outline the best affordable configuration
> i.e. Breakout board, Servo drives and Power Supply. What voltage and amperage
> would you suggest using the Gecko 320's. Any input on this would be greatly appreciated.
>
> Ron

Hi Ron:

To address the Power Supply issue, I run a cnc SuperMax using Gecko's
(although stepper G201's) and my 1 KW power supply (14Amps @ 75VDC, but
more amps as the voltage is drawn down). The SuperMax is a 4000 pound
mill with a 5 HP spindle. With my setup, I get 2 ips (120 inch/min) max speed,
and up to that speed in 1/4 second with two 100 lb vises on the table.
Its been running almost 2 years now.

If you are driving two servo axes HARD (ie 2 motors at 10A each), then my
1.5 KW unit gives 21 Amps continuous (or more amps as the voltage is drawn down).

Both units can do 150% of nominal for 30 minutes, and the big 47,000uF
capacitor can give large instantaneous currents, and certainly adding
a second cap in parallel can give you even greater instantaneous current
surges, as well as giving you a bigger buffer to protect against back EMF
(reassuringly, nobody has ever reported back EMF problems with my supply).

Hope this helps.

Regards
Doug Fortune
http://www.cncKITS.com