Hi All,
Appreciate the additional questions and replies as i have been "kind of" looking at BOB's.
A rock solid BOB  "without gremlins" is worth the elimination of possible aggrivation even at a increased
price. Not passing judgment, just trying to gain knowledge for down the road decisions.
RICH

Probably just a wider shot of the PMDX and SS. I've contacted the company that sells this unit and requested postal charges to Australia so I'm close to buying one.

Thanks in advance

Heres a pic of more of the cabinet, not sure its much of a help though.
Hood

Hi All,
Appreciate the additional questions and replies as i have been "kind of" looking at BOB's.
A rock solid BOB  "without gremlins" is worth the elimination of possible aggrivation even at a increased
price. Not passing judgment, just trying to gain knowledge for down the road decisions.
RICH

Hi Rich,

Whether you use a BOB with opto-isolation, is a decision that is made when looking at your system as a whole. If you have stepper drivers that already have opto isolation, then an opto-isolated BOB is likely to introduce problems.

If you are using opto sensors on inputs, then again you don't really want an opto isolated BOB. If your input switches are mechanical, then opto-isolation is good.

So in the end it depends on what other components you plan to use.


Cheers,

Peter.

Here is another nice pic of a Smooth Stepper installation with PMDX-122's.
http://www.machsupport.com/forum/index.php/topic,6406.msg43351.html#msg43351
Also, in response to post #2. hunserv said "and some protection"...the PMDX 122 is only buffered, not isolated.
Thanks,
RC 

Has anyone tried the C23 board from CNC4PC ?
  I am looking into getting that one but it is 198.00  , little pricey BUT after checking out what it has on it , it doesn't seem too bad , It is opto isolated and has  2 relays for motors and vacuum...
  I do live in the same city as him but have never bought one or met him..
Any Opinions on this board?
Here is a link   http://www.cnc4pc.com/Store/osc/product_info.php?cPath=33&products_id=182
Thanks
Gary

Never used that board but my personal opinion on any board and not particularily this one is that the more you have on a board that is sharing the 5v signals to Mach then the more problems you are likely to have. I prefer to have seperate  boards for relays etc but this is however just a personal opinion so take it as such.

Hood

Hi Hood,

So one cable from your SS goes to a PMDX board... and the other one? (which seems larger and uC equipped?)

That board is the Acustep BOB that CNC Building blocks made (no longer making them).
 The reason I used it was twofold, firstly it has Index homing on it and secondly it has differential step/dir outputs. I have been rewiring the cabinet the last few days and have now done away with that BOB as I do the index homing in my servo drives and I have made up a small board that clips direct into the PMDX and converts the single ended Step/Dir outputs to differential.
 Below is a pic of the cabinet now(red arrow points to differential board), I welded up a single Aluminium cabinet and everything is now in there instead of two seperate cabinets as before.

Hood

Neat! Are you using the encoder inputs of the SS as well? Generic inputs, or for spindle encoder?

I have also a single cabinet, but I do not use differential signals. However, I had some noise issues (from freq converter) so I had to shield the SS and the USB cable and put them as far from the converter as possible.

I have the spindle encoder in to the SS but only the Index pulse will be used at this time. The other inputs on port 3  I will connect to the MPG.

Never had a problem with noise and the SS but I try to shield all 5v signal wires and I use 24V for most things.

Hood