Connecting AB Ultra 3000 to Bob Campbell breakout board

[pvogtcharlotte]

Folks,
I have three brand-new Allen-Bradley servo drives and a Bob Campbell Breakout board. My plan is to configure the system and operate it with MACH3. My question is about interface the step and direction outputs from the breakout board to the servo drives. All the AB ultra drives can accept step and direction input, but each has two inputs (Step + and Step-) and (Dir+ and Dir-). I can't figure out how to connect this to the breakout board, and I am really afraid of burning up either the controller or the servo drives.
Can anyone help?
Thanks for any advice,
Paul Vogt,
Charlotte, NC

Two of the drives are Ultra 100 and one is an Ultra 3000

[wyobmf]

Hello,
Just wondering if you got your AB drives to work.
I am going to attempt the exact setup soon.
Thanks

[pvogtcharlotte]

WYOBMF,
Yes! In fact this works very well. There is a secret, and I will have to look through my notes in order to find out what it was. It was a particular jumper setting I think. Anyway it works very well, and no additional hardware was required. Send me an email if you like and I'll dig up more info.

I have bought two of the breakout boards, built two operational CNCs, and have had great fun, made money, and had zero problems.
Best Regards
Paul Vogt
Charlotte NC
pvogt@noltecse.com

[coolfox]

Originally Posted by pvogtcharlotte WYOBMF, Yes! In fact this works very well. There is a secret, and I will have to look through my notes in order to find out what it was. It was a particular jumper setting I think. Anyway it works very well, and no additional hardware was required. Send me an email if you like and I'll dig up more info. I have bought two of the breakout boards, built two operational CNCs, and have had great fun, made money, and had zero problems. Best Regards Paul Vogt Charlotte NC pvogt@noltecse.com

Paul,
I have Allen-Bradley servo drives and a Bob Campbell Breakout board. You mention on the cnczone about some clewer way to get differential step direction on the Ultra3000 to work from open collector output of the breakout board. Could you please share this invaluble infor to the forum members as there may be some doesn wonder arownd of the same dilemma.
Kind regards

[wyobmf]

If I remember right the Chambel board has active low outputs setup for Gekos and the ultra 3000 uses active high. I think you need an opto-issolator with the Chambel board, I used a PDMX that can be active low or high.

There is no "Secret" Just wire the Common, to the common on your BOB and then Just wire the step and direction single ended.
You can acomplish step and direction control with three wires.

[pvogtcharlotte]

Folks,
I worked this out some time ago with Bob Cambell's help. Here are some notes:

Dear Robert,
I found that once I moved the jumper from M1 to N1, my problem went
away. Also, the step and direction LEDs no longer turn on all at once when the reset button in Mach3 is pressed. Also, the random occurances of the
same fault have stopped.

I'm not an EE so I don't understand what is going on, but it is working
now.
Any final thoughts on the subject?
Thanks for your time,
Paul Vogt,
Charlotte, NC

Then this:
Paul,
What you have done is to turn off the charge pump safety signal.
I will have Jim Cullins the designer of the board to look at it.

Robert Colin Campbell
Bob Campbell Designs

Then this....

Paul,

The charge pump signal is being sent out from Mach. It is a continuous
10 or 12 KHZ signal that is detected on the breakout board. Once the
signal is detected it turns on out-4. You should see the led come on when you press the reset button. The charge pump signal is basically a safety device. If the connection to Mach is broken or the EPO switch is pushed, then the charge pump signalwill stop.

The charge pump signal then enable all outputs and enables the step and
direction signals to go to the drivers.

Robert Colin Campbell

Then this summary:
Robert,
Thanks for the information. Here are some details that someone might
find useful.
1) My application has two Alen-Bradley Ultra100 servo drives (Y & Z) and
one Allen-Bradley Ultra3000 Servo drive for the X axis.
2) The Allen-Bradley Ultra 3000 drive seemed to be immune to the
problem.
3) Both of the Allen-Bradley Ultra 100 drives (100 is an older model)
would quickly fault when the reset was pressed in Mach3
It may take 5-6 presses to trigger the fault, but it would always
happen. The fault also happened sporadicly, for no known
reason in the middle of running a part file.
4) The fault reported by the drives is "Master Encoder Illegal State
Fault"
5) Allen Bradley tech support was only able to tell me "use shielded
cable, it's a noise problem" (gosh, thanks!) (all my
cables are properly shielded)
6) My impression is that moving the jumper to N1 position immediately
solved the problem.
7) The (J24)jumper for the step/direction output is set for GND. This
was necessary to interface to the AB drives.
I may have to double check this, but I'm thinking that the jumper
sets the reference to 0V, meaning the steps are
+5 volt steps, referenced to common, which is at ground. This detail
is from memory, and I will confirm tomorrow.

I hope this is useful to someone,
Robert, I love your product, Thanks for making it.

Best Regards,
Paul

And this suggestion, which I have not done:

Paul,
When the jumper is in M1 and a reset is given the output buffers go into high impedance mode and are floating. With a opto coupled motor drive this is no problem how ever as with you drive having the inputs float makes it very sensitive to noise. In the N1 mode the outputs are always driven so you have no problems. I would try to put a 1k resistor from the step out terminal to the com on the screw terminal on the breakout board.
Sorry for your problem but I am glad you explained it well as I have not had that problem mentioned before.
Thanks
Jim Cullins
Sound Logic