AB Ultra 3000 in follower mode

[lurby]

I have posted a similar question before but I am revisiting the project and would like to ask again.

I am setting up an Allen Bradley Ultra 3000 (lets say 2098-DSD-020) in Follower:Aux Encoder mode. This mode will give me eight preset gear ratios to choose from in the follower window of Ultraware. I would like more.

How do I do this? I know that I can change them all day long with my laptop connected and Ultraware up and running. I would like to use an operator interface to be able to change the ratio.

Taking it one step further I would like to be able to scale the input.

I would like to keep any processor that I might use to a minimum. I would like to stay in the MicroLogix family for cost and programming comfort reasons.

Thanks.

 

[kolyur]

Unless you have a Devicenet or Sercos enabled drive, your only option for changing drive parameters on-the-fly (including the follower ratios) is through the serial interface. Hardware-wise, this could be done with nothing more than a Micrologix PLC and a serial cable. However, the ladder programming required to create and parse the ASCII serial commands would be considerable. (This topic has been discussed on this forum in the past.)

You mention using an operator interface... the Red Lion G3 units have a Ultra 3000 driver built-in and will talk to Micrologix PLCs also. Or just spring for the Data Station (same as a G3 without the screen) to transfer the parameters between the Micrologix and Ultra 3000. I've used both and the Ultra3000 driver is solid. More detail on this solution in this thread:
http://www.plctalk.net/qanda/showthread.php?t=22687

 

[lurby]

Thanks. I talked to Red Lion last night and it sounds like it might work. My AB salesman is talking SERCOS or DeviceNet. Should I look at this or will I be opening up a can of worms?

 

[bkottaras]

No can of worms.
Just get ready to pay through the nose for the additional hardware.
And in case of Device-net for the software as well!

 

[OkiePC]

Thanks. I talked to Red Lion last night and it sounds like it might work. My AB salesman is talking SERCOS or DeviceNet. Should I look at this or will I be opening up a can of worms?

How many drives? If there are a lot of drives, you may want to consider D-net or sercos with a Logix PAC.

If more than one do you need coordinated motion between them? I think if you need coordinated motion then Sercos might be worth consideration.

If it's just one drive or very few, I would not bother with either unless you need to move lots of data frequently and are already using one of those networks for other equipment.

 

[kolyur]

If it's just one drive or very few, I would not bother with either unless you need to move lots of data frequently and are already using one of those networks for other equipment.

Agreed, I think serial makes the most sense based on the information you've provided. Go for the Red Lion solution, no worries.

 

[lurby]

Thanks for your help everyone. I think I will go with the Red Lion. Under $500 with the cabling can't be beat! There is only one servo drive on the system and I only need the Red Lion to access one parameter on the drive (follower gear ratio). The rest will be done with plain old push buttons.
Can anyone recommend an inexpensive linear encoder? Some of these things are outrageously priced and actually far more accurate than I really need.

 

[OkiePC]

Can anyone recommend an inexpensive linear encoder? Some of these things are outrageously priced and actually far more accurate than I really need.

Linear encoder? How long is the line it's measuring? How accurate does it need to be?

 

[kolyur]

If you have any trouble with the Red Lion / Ultra3000 comms, feel free to post here. We've done it before and can help.

I have used MTS/Temposonics in the past for linear encoders. Not sure how you'd define "outrageously priced" but I've used their ER series encoder with good results and as I recall it was a few hundred $$$ for a model with several inches of stroke.

http://www.mtssensors.com/