Re: Need to upgrade controls

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "terrygh1" <terrygh@w...>
wrote:

> Hello all, I hope some of you can help me with this project.
> I have two YCI cnc mills circa 1980 using Bandit controls,
> with level 3 firmware. I would like to upgrade both controls to
> something newer, these machines both have 400 oz-in servo motors
> rated at 80 vdc with tach feedback and resolves. I would like to
> retain the servo motors, the power supply and the driver boards.

The

> reason being the tach feedback which is, 3vdc per 1000 rpm, is
> connected to the driver board for a closed loop torque feedback.
> From reading the setup information for the driver board it seems

that

> the driver signal voltage is +/- 10vdc.
> The resolves are connected to the Bandit resolver logic board
> and are driven off the back of the servo motors. The resolver
> information I have is, Summit Engineering Corp., Bozeman Mt.,

2500hz,

> rotor phase 1 output 5.0 volts, stator 2 phase input 12 volts.

These

> will probably have to be upgraded to new encoders that will work

with

> the new control software
> Both mills have 3 phase 220vac Dana Condor spindle drives that are
> controlled via the Bandit. This drive uses an analog input signal
> for speed control and relay logic for spindle direction. I would
> also like to retain these spindle drives if possible.
> I have all the prints for the Bandit control, the set up
> procedure for the driver boards, along with prints for the Condor

VFD.

> I would like to control these machines with my notebook
> computer it has parallel, serial and usb2 ports.
> If anyone has any information which would help me upgrade
> these machines I sure would appreciate it.
>
> Thanks Terry Huntington

Terry: Most of the "hobby" (not meaning less accurate or lower
performance) controls used by the list guys use encoder (digital)
feedback for postional information. If your Bandit (sorry not
familiar with that controller) can be split up so that you retain the
motors and driver cards and the resolver interface and it's done in
hardware then there may be hope. If on the other hand you need the
software to close the servo loop using the tach and resolver feedback
then its going to get harder.

Most of the systems we use are not closed loop SOFTWARE systems
(exception Jon's offering running with EMC on LINUX). They are based
around some of the servo motor controller modules from Gecko
(www.geckodrives.com) or Rutex (www.rutex.com). They use encoders as
feedback and adjust the motor speed by comparing the step and
direction signals from a parallel port to the encoder count.

Resolvers require a lot of complex external circuitry since they use
an AC wave and phase angle comparisons to get the positional info.

If your goal is to use a PC to control your machine directly then
here is some homework for you to do:

http://www.pico-systems.com/ (Jon's home)
http://www.artofcnc.ca (Windows based control software)
http://www.dakeng.com/ (TurboCNC DOS based control software)
http://www.imsrv.com/deskcnc/ (Windows based CAM/Controller -
requires external hardware)
http://www.geckodrives.com (Stepper and servo drive modules to 80V)
http://www.rutex.com (Servo drive modules to 200V)
http://www.sheetcam.com (low cost CAM program in Beta)

Groups that support these products are here on Yahoo. Another group
to check out is: DIY-CNC.

Don't mean to answer your questions with web locations but if you go
to the ones above you will start to get a basis of the available
technology and then the answers will be more meaningful.

Let us know how we can help.

Tom C