# Help- Servo Amp -vs- Drive question?  Old Bandit 3 w/ MSI MM3-CCC--09 Servo drive/amp??



## countryguy (Jan 19, 2015)

Hi everyone and good evening.   Before I take the plunge on the AjaxCNC setup - I have been in contact w/ one of the original developers of the Dynetics/Bandit controller. Name is Len and a GREAT guy.   He thinks this thing is really close and just needs a little push on the Drive connections for the MSI>>>    But this stuff is all soooooo OLD!  
thought I'd punt and see if I can pull a 'seahawks' TD here.  

This Mill has been sort of setup w/ the parts -But not all the connections.   the MSI MM3-CCC-09 is listed as both a server drive and amp.  Are these the same thing? 

Also - The inputs from the Bandit3 need to go to the amp/drive.  All I see on the MSI board for inputs is show in the pics below.  +IN -IN +TH -TH and EN   in yellow below. 

*So Here goes: *
A)  I have 6 sets of wires.  2 sets of X, Y, Z.  Total 6 sets.  
B) 1 set comes from the Bandit3's "Channel 0,  1, and 2.  I've ohmed them back to that.   TWO Wires.  A black and a white.  
C) From the DC motor cables, thru the *conduit and into the cabinet- is the 2nd set.  There is a Blue, White, and Black in each bundle.  The bundles are labled X, Y, Z.    
           * I will pull the molex circle conn off and ohm these back to the X motor I've yanked apart tomorrow. 

Somehow this just needs to be connected together and I think I could try to power everything up? Just not sure what goes into the MSI amp/drive connectors +/-IN and +/-TH and EN locations. That's 5 wire spots. I have 5 wires per set of X,Y, Z. and five signal spots on the MSI for each X,Y,Z ????? is that a BIG leap??? 

I belive someone started to upgrade this unit some time ago and simply did not complete (obviously) the DC motor to Amp/Driver setups.  Not even sure all the right gear is there technically.


----------



## JimDawson (Jan 19, 2015)

The terms drive and servo amp can be used interchangeably.  Technically, it is an amp, but in normal conversation they are just called a drive.

Is there any documentation available on those boards?  A quick search didn't turn up anything.  The terminal designations are not familiar to me.  I think the EN = Enable,  IN+ and IN- might be the +/- 10 volt command signal from the computer, and the TH+ and TH- might be the tachometer feedback from the motor. That in addition to the power wires to the motor should be enough to run it.


----------



## countryguy (Jan 19, 2015)

a GREAT Read on Servo basics!  Go Baldor!     Seems an AMP is a DRIVE and both represent a task or function block.  Cool! 
page 11
View attachment servo-basics-1205-394.pdf


----------



## countryguy (Jan 20, 2015)

I do agree and think we have the Tach feedback on TH lines and the and controller channels's = the 10V sigs....  Anyway- Gonna try it.   Not sure why the former owner said I needed the new drives? and then there is a set in there?   Maybe since he could not find any MSI info either.    They are Long Gone and I cannot even find a mention of them anyplace.  I think they were an OEM supplier to ab/rockwell and others.  All lit and materials thru them.  Checking the rockwell lit lib when I can later. 

Thanks Jim!
JJ 




JimDawson said:


> The terms drive and servo amp can be used interchangeably.  Technically, it is an amp, but in normal conversation they are just called a drive.
> 
> Is there any documentation available on those boards?  A quick search didn't turn up anything.  The terminal designations are not familiar to me.  I think the EN = Enable,  IN+ and IN- might be the +/- 10 volt command signal from the computer, and the TH+ and TH- might be the tachometer feedback from the motor. That in addition to the power wires to the motor should be enough to run it.


----------



## countryguy (Jan 20, 2015)

Here is what I think I'll pursue today or tomorrow... depending on work issues.  Take the Bandit 3 and get this beast powered up.   Needs a few wires connected and some ohm-out's but should be 30mins tops.    Power it all up, and see if I can figure out how to jog around a bit while taking the O-scope to the channel-out XYZ pairs from the Bandit.  And I'll watch the probable Tach (encoder) wires inputs. (spin by hand??)  If this all shakes out OK, should be able to get this all connected up.   The EN signal me has me worried but it may not even by used.  Plus the MSI had a large dip-switch bank to setup for the Motor's w/ resistive/ capacitive networks for tuning and Amp parms.    I think maybe the AjaxCNC DSP is the better choice but I may as well see???     or should I just start yanking this all out since I have zero manuals and nobody has them to offer up either.   It feels like fool's gold errand mostly!


----------



## JimDawson (Jan 20, 2015)

Let us know what happens.  I assume you have the drive belts off of the motors.  The tachs are normally a generator and output about 7 volts / 1000 rpm.


----------



## countryguy (Jan 20, 2015)

LOL... belts off.. Umm No. They are still on except for X which is torn down.  Thanks!  good call.  

  I've called 3 places looking for some cheap drive's !  The MSI unit is not cheap.. I know that.    It was put in hoping to rebuilt it w/ them... But the old owner noted they were probably a lost cause.  Now I know why!!! 

  I'll sell the MSI off on EBAY to recoup some money maybe.    We're talking a Grand Min for 80's junk AMPs from my Bandit3/AB source.  And then $1.5 -2K for newer used stuff from repair houses and tested resellers.    I am trying to use qualified vendor's not junk pullers on ebay.   Been there done that.  So it's $$$ and here is the the part I think I'm glad to say:   For $1.8K I can just make the call to AjaxCNC.  I've been so flippin' happy w/ 1 hour reply times on the forums and CNCzone from their support guys on Q's related to their stuff..  So the phone is in my hand.  The Order shall go in ...
5, 4,  3 ,,, 2,.... 1  (maybe).  LOL.  No, really I am going to call them now.    Zero. :victory:
CG out. 






JimDawson said:


> Let us know what happens.  I assume you have the drive belts off of the motors.  The tachs are normally a generator and output about 7 volts / 1000 rpm.


----------



## fahrphrompuken (Mar 24, 2015)

If you're looking for new analog brushed-motor servo amps, Servo Dynamics still makes them. These are the ones that replaced the old 1500 series that Dynapath used for all of their upgrade packages.

http://www.servodynamics.com/Br_Brs.html
They support single ended or differential signal input, tach (7v/k) , and fault shutdown. I installed one to replace a failed worn out Motion Science unit on a Bridgeport EZ path, and it works great, $$ is somewhere around $700 per axis.


----------



## countryguy (Mar 24, 2015)

Thanks a ton for that info.  I'll be sure to pass it along to someone if I get the old Bandit III sold.  I know the price was into the $1500 range for the 3 drives.  But it was left w/ 500 line encoders, and an 80's board set w/ 4 power supplies alone.  This thing was a beast and I did not wish to spend that kind of money on something so old.      So I went w/ the Ajax / Centroid setup.    But I do appreciate your lead here!    Thanks again!


----------



## fahrphrompuken (Mar 24, 2015)

You'll be way happier with the new setup, which is light years ahead of the old Bandit.


----------

