[CNC_Newbi]

I Need Help!
I have an old, small knee mill and controller from the 80's with 2- spindles and 2- Z axis.
The pieces:
• 4 Brush Servos w/Tach and Encoders (Encoders_5v, 8 leads)
(Servo Dynamics)
• 4 D/A Boards (Servo Dynamics)
• 4 Servo Amplifier boards (Voltage: Peak/Continuous_100/92,
Current: Peak/Continuous_15/10 Amps) (Servo Dynamics)
• 1 Numericon 850 Controller (Pre DOS?_big _difficult input_impossible
output_program dumps every time the controller is shut off,
default often, must shut off at every default)

Recently the Y axis went nuts and continued to drive the servo anytime power was applied without a program running or any manual jogging input.
I traded the D/A board with another axis and the problem transfered to that axis.
The mill has 2 spindles and 2 Z axis so I eliminated the second Z axis and used that board for the Y axis.
This worked fine and I was able to proceed _For several days.
Then the controller screen displayed "Excess Error", the D/A board red lighted and I can't control a thing.
(104v are are being sent to the servo anytime the 15+/- Bias Power is supplied to the Model 1015-10 Amplifier board)


I swapped encoders_No change.
Opened servos_Some coolant and brush dust_Cleaned up/No help.
(Damage already done to boards?)

Do you have any suspicions as to what initiated the failures?
What options do I have?
Dump controller and boards_Run Mach2/3 with modern boards?
What integration issues will I encounter if I try to retain the Motors, Tach & Encoders?

Thanks In Advance For Your Help!

[CJL5585]

I Need Help!

What options do I have?

Dump controller and boards_Run Mach2/3 with modern boards?

What integration issues will I encounter if I try to retain the Motors, Tach & Encoders?

Thanks In Advance For Your Help!

First of all, I would like to say that I am sorry to hear that your machine has died such a terrible, tragic death.

I think that you may have 3 options:

Option 1 is that you know of an identical machine with the same electronic controls (which are guaranteed to be operational) and replace all defective circuit boards. (Will you blow additional circuit boards? How long will these other boards continue to function?)

Option 2 is to get a field service tech to troubleshoot the defective components and repair the defective boards. (Worst and most expensive Option)

In my opinion, I think the least expensive route is Option 3 as follows:

Replace the controls with Gecko 320 or 340 Servo drives. (Cost approx. $134.00 each) You can use your existing servo's and most likely the encoders, HOWEVER, you would have to replace the unit power supply. (About $250.00 unless you build your own for about $100.00)

Use a computer running Mach software and a parallel port breakout board ($25.00 - $135.00 depending on preference) which will accept the tach inputs for spindle speed control.

The integration issue depends upon your ability to read wiring diagrams, to perform some wiring tasks, to set up the computer and the Mach software, and to do some possible troubleshooting if everything does not work the first time around.

However, the wiring of the drives, encoders (provided you have schematic or know which wires are +5V, common, A phase, B phase) should not be a difficult task since there are wiring diagrams for the drives, servos, and encoders on this site.

This is just my opinion. Good Luck.

[CNC_Newbi]

Thanks for the reply and the sentiments CJ,
I think that you are probably right and that is were I'll end up.

To clarify, the Tach I mentioned was on the servos. I haven't seen any boards that utilize this signal. Geckos look good but Rutex looks to be a better match power and current wise. Still unsure but both seam to have a good reputation and the Rutex also has a optical isolated mother board.

Any other suggestions by anyone before the plastic comes out?
Any preference Geckos/Rutex.
Is there anything I should be looking for that I'm not seeing?